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App stopped working as soon as i clicked the button

I built a simple project that squares a given number. In that app as soon as i click the button "Calculate" it say's "Unfortunately, SquareCalculator has stopped". What should i do to resolve the problem?
Below is my entire code:-
MainActivity.java
package thenerdimite.squarecalculator;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
protected void calculate (View v){
EditText input = (EditText) findViewById(R.id.etInput);
TextView output = (TextView) findViewById(R.id.tvOutput);
int base = Integer.valueOf(input.getText().toString());
int result = base * base;
String formattedResult = String.format("%,d", result);
output.setText("Result: " + formattedResult);
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="thenerdimite.squarecalculator.MainActivity">
<EditText
android:id="#+id/etInput"
android:layout_width="245dp"
android:layout_height="41dp"
android:layout_marginTop="15dp"
android:ems="10"
android:inputType="number"
tools:layout_editor_absoluteX="16dp"
tools:layout_editor_absoluteY="62dp"
android:layout_below="#+id/tvInput"
android:layout_alignStart="#+id/tvInput" />
<Button
android:id="#+id/btnCalculate"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignStart="#+id/etInput"
android:layout_below="#+id/etInput"
android:layout_marginTop="20dp"
android:onClick="Calculate"
android:text="Calculate"
android:textSize="18sp" />
<TextView
android:id="#+id/tvOutput"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Result:"
android:textAppearance="#style/TextAppearance.AppCompat.Display1"
android:layout_below="#+id/btnCalculate"
android:layout_alignStart="#+id/btnCalculate"
android:layout_marginTop="18dp" />
<TextView
android:id="#+id/tvInput"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Enter an Integer:"
android:textAppearance="#style/TextAppearance.AppCompat.Display1"
android:layout_marginStart="19dp"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
logcat
04-25 09:28:05.060 3596-3596/thenerdimite.squarecalculator D/AndroidRuntime: Shutting down VM
04-25 09:28:05.060 3596-3596/thenerdimite.squarecalculator W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0xa5007678)
04-25 09:28:05.060 3596-3596/thenerdimite.squarecalculator E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.IllegalStateException: Could not find method Calculate(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'btnCalculate'
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.resolveMethod(AppCompatViewInflater.java:327)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:284)
at android.view.View.performClick(View.java:4240)
at android.view.View$PerformClick.run(View.java:17721)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
04-25 09:28:06.740 3596-3596/? I/Process: Sending signal. PID: 3596 SIG: 9
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="thenerdimite.squarecalculator">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Using the documentation of Button
You see the method need to be public and accept a View
In order for this to work, the method must be public and accept a View as its only parameter.
So it should be
public void Calculate (View v){
Using the xml notation, of course, you should call it calculate and correct the XML

From what I see, the problem is that your button action is android:onClick="Calculate" but should be android:onClick="calculate"

you need to make the method public, protected and private methods are not accessible by xml.
public void calculate (View v){
EditText input = (EditText) findViewById(R.id.etInput);
TextView output = (TextView) findViewById(R.id.tvOutput);
int base = Integer.valueOf(input.getText().toString());
int result = base * base;
String formattedResult = String.format("%,d", result);
output.setText("Result: " + formattedResult);
}

Change android:onClick="Calculate" to android:onClick="calculate".
Also calculate method should be public.

In XML you have "Calculate" with capital "C" while method is called "calculate". Change XML and it should work.
https://developer.android.com/reference/android/widget/Button.html

How to create a map activity in one activity on button click in other activity?

I am creating an android app for an University. I am trying to display a Location map in one activity by clicking a button in other activity. I have referred some links and worked, but I am getting error. Here is my code snippet and the Logcat. Please anybody help me in making this work.
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.university"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" />
<permission
android:name="com.example.university.permission.MAPS_RECEIVE"
android:protectionLevel="signature" />
<uses-permission android:name="com.example.university.permission.MAPS_RECEIVE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature android:glEsVersion="0x00000000" android:required="true" />
<meta-data android:name="com.google.android.maps.v2.API_KEY"
android:value="AIzaSyDGPcb88FGrYilWxe41RbWog38pSgNfp5o" />
<application android:allowBackup="true" android:icon="#drawable/launcher"
android:theme="#style/Theme.AppCompat.Light" >
<activity android:name=".MainActivity" android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".About" android:label="#string/title_activity_about" >
</activity>
<activity android:name=".Chancellor" android:label="#string/title_activity_chancellor" >
</activity>
<activity android:name=".Prochancellor" android:label="#string/title_activity_prochancellor" >
</activity>
<activity android:name=".Programs" android:label="#string/title_activity_programs" >
</activity>
<activity android:name=".Contact" android:label="#string/title_activity_contact" >
</activity>
<activity android:name=".SplashActivity" android:label="#string/title_activity_splash" >
</activity>
<activity android:name=".Admissions" android:label="#string/title_activity_admissions" >
</activity>
<activity android:name=".Map" android:label="#string/title_activity_map" >
</activity>
</application>
</manifest>
THIS .JAVA AND .XML FILES FOR BUTTON AND ONCLICK FUNCTION TO WORK
Contact.java
package com.example.university;
import android.support.v7.app.ActionBarActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.view.View.OnClickListener;
public class Contact extends ActionBarActivity {
Button button;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the view from activity_contact.xml
setContentView(R.layout.activity_contact);
// Locate the button in activity_contact.xml
button = (Button)findViewById(R.id.button1);
// Capture button clicks
button.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
// Start NewActivity.class
Intent myIntent = new Intent(Contact.this,
Map.class);
startActivity(myIntent);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.contact, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
switch (item.getItemId()) {
case R.id.about:
Intent a = new Intent(getApplicationContext(), About.class);
startActivity(a);
return true;
case R.id.chancellor:
Intent b = new Intent(getApplicationContext(), Chancellor.class);
startActivity(b);
return true;
case R.id.prochancellor:
Intent c = new Intent(getApplicationContext(), Prochancellor.class);
startActivity(c);
return true;
case R.id.programs:
Intent d = new Intent(getApplicationContext(), Programs.class);
startActivity(d);
return true;
case R.id.admissions:
Intent e = new Intent(getApplicationContext(), Admissions.class);
startActivity(e);
return true;
case R.id.contact:
Intent f = new Intent(getApplicationContext(), Contact.class);
startActivity(f);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
activity_contact.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/tiny_grid"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.university.Contact" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:src="#drawable/campus1" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/imageView1"
android:layout_marginLeft="26dp"
android:layout_toRightOf="#+id/imageView1"
android:text="100 Feet Ring Road, BSK III Stage, Bangalore-560085"
android:textSize="11dp" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView1"
android:layout_below="#+id/textView1"
android:text="+91 80 26721983"
android:textSize="11dp" />
<TextView
android:id="#+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView2"
android:layout_below="#+id/textView2"
android:text="+91 80 26722108"
android:textSize="11dp" />
<TextView
android:id="#+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView3"
android:layout_below="#+id/textView3"
android:autoLink="email"
android:text="admissions#pes.edu"
android:textSize="11dp" />
<ImageView
android:id="#+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/imageView1"
android:layout_marginTop="20dp"
android:layout_toLeftOf="#+id/textView1"
android:src="#drawable/campus2" />
<TextView
android:id="#+id/textView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView4"
android:layout_alignTop="#+id/imageView2"
android:text=" Hosur Road Campus (1 Km before Electronic City), Bangalore - 560 100"
android:textSize="11dp" />
<TextView
android:id="#+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView5"
android:layout_below="#+id/textView5"
android:text="+91 80 66186610"
android:textSize="11dp" />
<TextView
android:id="#+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView6"
android:layout_below="#+id/textView6"
android:text="+91 80 66186611"
android:textSize="11dp" />
<TextView
android:id="#+id/textView8"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView7"
android:layout_below="#+id/textView7"
android:autoLink="email"
android:text="admissions#pes.edu"
android:textSize="11dp" />
<ImageView
android:id="#+id/imageView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/imageView2"
android:layout_marginTop="25dp"
android:layout_toLeftOf="#+id/textView1"
android:src="#drawable/campus3" />
<TextView
android:id="#+id/textView9"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView8"
android:layout_alignTop="#+id/imageView3"
android:text="National Highway 219, Kuppam, Andhra Pradesh - 517 425"
android:textSize="11dp" />
<TextView
android:id="#+id/textView10"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView9"
android:layout_below="#+id/textView9"
android:text="085 70 256736"
android:textSize="11dp" />
<TextView
android:id="#+id/textView11"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView10"
android:layout_below="#+id/textView10"
android:autoLink="email"
android:text="admissions#pes.edu"
android:textSize="11dp" />
<ImageView
android:id="#+id/imageView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/imageView3"
android:layout_marginTop="20dp"
android:layout_toLeftOf="#+id/textView1"
android:src="#drawable/campus4" />
<TextView
android:id="#+id/textView12"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView11"
android:layout_alignTop="#+id/imageView4"
android:text="100 Feet Ring Road, BSK III Stage, Bangalore-560085"
android:textSize="11dp" />
<TextView
android:id="#+id/textView13"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView12"
android:layout_below="#+id/textView12"
android:text="+91 80 26721983"
android:textSize="11dp" />
<TextView
android:id="#+id/textView14"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView13"
android:layout_below="#+id/textView13"
android:text="+91 80 26722108"
android:textSize="11dp" />
<TextView
android:id="#+id/textView15"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView14"
android:layout_below="#+id/textView14"
android:autoLink="email"
android:text="admissions#pes.edu"
android:textSize="11dp" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/imageView4"
android:layout_alignParentBottom="true"
android:layout_marginLeft="16dp"
android:text="Button" />
</RelativeLayout>
THIS .JAVA NAD .XML FILES TO DISPLAY MAP
package com.example.university;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import android.support.v7.app.ActionBarActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.util.Log;
import android.widget.Toast;
public class Map extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getApplicationContext());
if (resultCode == ConnectionResult.SUCCESS){
Toast.makeText(getApplicationContext(),
"isGooglePlayServicesAvailable SUCCESS",
Toast.LENGTH_LONG).show();
}else{
}
}
#Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getApplicationContext());
if (resultCode == ConnectionResult.SUCCESS){
Toast.makeText(getApplicationContext(),
"isGooglePlayServicesAvailable SUCCESS",
Toast.LENGTH_LONG).show();
Log.v(">>>>>>>>>>>>>.", "successs");
}else{
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.map, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
switch (item.getItemId()) {
case R.id.about:
Intent a = new Intent(getApplicationContext(), About.class);
startActivity(a);
return true;
case R.id.chancellor:
Intent b = new Intent(getApplicationContext(), Chancellor.class);
startActivity(b);
return true;
case R.id.prochancellor:
Intent c = new Intent(getApplicationContext(), Prochancellor.class);
startActivity(c);
return true;
case R.id.programs:
Intent d = new Intent(getApplicationContext(), Programs.class);
startActivity(d);
return true;
case R.id.admissions:
Intent e = new Intent(getApplicationContext(), Admissions.class);
startActivity(e);
return true;
case R.id.contact:
Intent f = new Intent(getApplicationContext(), Contact.class);
startActivity(f);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
Aactivity_map.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.university.Map" >
<fragment
android:id="#+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
Here is the Logcat when i click on the button in activity_contact.xml
07-26 02:22:16.012: I/Process(2244): Sending signal. PID: 2244 SIG: 9
07-26 02:22:20.062: D/dalvikvm(2268): GC_FOR_ALLOC freed 86K, 7% free 2998K/3200K, paused 221ms, total 269ms
07-26 02:22:20.292: I/dalvikvm-heap(2268): Grow heap (frag case) to 6.783MB for 3932172-byte allocation
07-26 02:22:20.372: D/dalvikvm(2268): GC_FOR_ALLOC freed 2K, 3% free 6835K/7044K, paused 79ms, total 79ms
07-26 02:22:21.552: D/gralloc_goldfish(2268): Emulator without GPU emulation detected.
07-26 03:10:59.626: D/dalvikvm(2376): GC_FOR_ALLOC freed 90K, 7% free 2997K/3204K, paused 191ms, total 202ms
07-26 03:10:59.876: I/dalvikvm-heap(2376): Grow heap (frag case) to 6.782MB for 3932172-byte allocation
07-26 03:11:00.126: D/dalvikvm(2376): GC_FOR_ALLOC freed 2K, 4% free 6835K/7048K, paused 248ms, total 248ms
07-26 03:11:07.206: D/gralloc_goldfish(2376): Emulator without GPU emulation detected.
07-26 03:11:09.626: D/dalvikvm(2376): GC_FOR_ALLOC freed 57K, 3% free 7068K/7260K, paused 31ms, total 36ms
07-26 03:11:09.896: I/Choreographer(2376): Skipped 58 frames! The application may be doing too much work on its main thread.
07-26 03:11:10.356: I/Choreographer(2376): Skipped 38 frames! The application may be doing too much work on its main thread.
07-26 03:11:21.527: D/dalvikvm(2376): GC_FOR_ALLOC freed 1266K, 17% free 7055K/8436K, paused 173ms, total 176ms
07-26 03:11:25.347: D/AndroidRuntime(2376): Shutting down VM
07-26 03:11:25.357: W/dalvikvm(2376): threadid=1: thread exiting with uncaught exception (group=0xb0cefb20)
07-26 03:11:25.397: E/AndroidRuntime(2376): FATAL EXCEPTION: main
07-26 03:11:25.397: E/AndroidRuntime(2376): Process: com.example.university, PID: 2376
07-26 03:11:25.397: E/AndroidRuntime(2376): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.university/com.example.university.Map}: android.view.InflateException: Binary XML file line #11: Error inflating class fragment
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread.access$800(ActivityThread.java:135)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.os.Handler.dispatchMessage(Handler.java:102)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.os.Looper.loop(Looper.java:136)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread.main(ActivityThread.java:5017)
07-26 03:11:25.397: E/AndroidRuntime(2376): at java.lang.reflect.Method.invokeNative(Native Method)
07-26 03:11:25.397: E/AndroidRuntime(2376): at java.lang.reflect.Method.invoke(Method.java:515)
07-26 03:11:25.397: E/AndroidRuntime(2376): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
07-26 03:11:25.397: E/AndroidRuntime(2376): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
07-26 03:11:25.397: E/AndroidRuntime(2376): at dalvik.system.NativeStart.main(Native Method)
07-26 03:11:25.397: E/AndroidRuntime(2376): Caused by: android.view.InflateException: Binary XML file line #11: Error inflating class fragment
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
07-26 03:11:25.397: E/AndroidRuntime(2376): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:290)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Activity.setContentView(Activity.java:1929)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.support.v7.app.ActionBarActivity.superSetContentView(ActionBarActivity.java:217)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.support.v7.app.ActionBarActivityDelegateICS.setContentView(ActionBarActivityDelegateICS.java:110)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.support.v7.app.ActionBarActivity.setContentView(ActionBarActivity.java:77)
07-26 03:11:25.397: E/AndroidRuntime(2376): at com.example.university.Map.onCreate(Map.java:20)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Activity.performCreate(Activity.java:5231)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
07-26 03:11:25.397: E/AndroidRuntime(2376): ... 11 more
07-26 03:11:25.397: E/AndroidRuntime(2376): Caused by: android.app.Fragment$InstantiationException: Unable to instantiate fragment com.google.android.gms.maps.SupportMapFragment: make sure class name exists, is public, and has an empty constructor that is public
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Fragment.instantiate(Fragment.java:597)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Fragment.instantiate(Fragment.java:561)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Activity.onCreateView(Activity.java:4778)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
07-26 03:11:25.397: E/AndroidRuntime(2376): ... 24 more
07-26 03:11:25.397: E/AndroidRuntime(2376): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.google.android.gms.maps.SupportMapFragment" on path: DexPathList[[zip file "/data/app/com.example.university-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.university-2, /system/lib]]
07-26 03:11:25.397: E/AndroidRuntime(2376): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
07-26 03:11:25.397: E/AndroidRuntime(2376): at java.lang.ClassLoader.loadClass(ClassLoader.java:497)
07-26 03:11:25.397: E/AndroidRuntime(2376): at java.lang.ClassLoader.loadClass(ClassLoader.java:457)
07-26 03:11:25.397: E/AndroidRuntime(2376): at android.app.Fragment.instantiate(Fragment.java:583)
07-26 03:11:25.397: E/AndroidRuntime(2376): ... 27 more

You are doing a few things wrong as you probably didn't follow all the steps in using Google Maps on your application:
Google Maps API key is supposed to be inside of the application tags in your manifest.
You are missing the play services meta tag (also inside the application tags):
<meta-data
android:name="com.google.android.gms.version"
android:value="#integer/google_play_services_version" />
Also make sure that you are compiling the play services with your project. If you're using Android-Studio, then the bottom of your build.gradle file should look like this:
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:20.+'
compile 'com.google.android.gms:play-services:5.0.77'
}

Unfortunately the Wifi Scanner has stopped [closed]

Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers.
This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers.
Closed 8 years ago.
Improve this question
I was trying to make a wifi scanner which can show the list of all the wifi access points. My code is as following :
MainActivity.java :
package com.example.wifiscanner;
import java.util.List;
import android.annotation.SuppressLint;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.wifi.ScanResult;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
public class MainActivity extends ActionBarActivity {
WifiManager wifi;
WifiScanReceiver wifireciever;
Button scan;
List<ScanResult> wifilist;
ListView list;
String wifis[];
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
list=(ListView)findViewById(R.id.listView1);
scan=(Button)findViewById(R.id.button1);
scan.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
wifi=(WifiManager)getSystemService(Context.WIFI_SERVICE);
if (wifi.isWifiEnabled()==false){
wifi.setWifiEnabled(true);
}
wifireciever = new WifiScanReceiver();
registerReceiver(wifireciever, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
wifi.startScan();
}
});
}
protected void onPause() {
unregisterReceiver(wifireciever);
super.onPause();
}
protected void onResume() {
registerReceiver(wifireciever, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
super.onResume();
}
class WifiScanReceiver extends BroadcastReceiver {
#SuppressLint("UseValueOf")
public void onReceive(Context c, Intent intent) {
List<ScanResult> wifilist = wifi.getScanResults();
wifis = new String[wifilist.size()];
for(int i = 0; i < wifilist.size(); i++){
wifis[i] = ((wifilist.get(i)).toString());
}
list.setAdapter(new ArrayAdapter<String>(getApplicationContext(),
android.R.layout.simple_list_item_1,wifis));
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
fragment_main.xml :
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.wifiscanner.MainActivity$PlaceholderFragment" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/button1"
android:layout_centerHorizontal="true" >
</ListView>
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/listView1"
android:layout_alignParentTop="true"
android:layout_marginLeft="34dp"
android:layout_marginTop="37dp"
android:minWidth="#dimen/abc_action_bar_stacked_tab_max_width"
android:text="Scan" />
</RelativeLayout>
Log cat :
05-26 09:41:49.840: D/AndroidRuntime(11186): Shutting down VM
05-26 09:41:49.840: W/dalvikvm(11186): threadid=1: thread exiting with uncaught exception (group=0x414f82a0)
05-26 09:41:49.861: E/AndroidRuntime(11186): FATAL EXCEPTION: main
05-26 09:41:49.861: E/AndroidRuntime(11186): java.lang.SecurityException: WifiService: Neither user 10105 nor current process has android.permission.ACCESS_WIFI_STATE.
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Parcel.readException(Parcel.java:1425)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Parcel.readException(Parcel.java:1379)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.net.wifi.IWifiManager$Stub$Proxy.getWifiEnabledState(IWifiManager.java:900)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.net.wifi.WifiManager.getWifiState(WifiManager.java:1078)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.net.wifi.WifiManager.isWifiEnabled(WifiManager.java:1090)
05-26 09:41:49.861: E/AndroidRuntime(11186): at com.example.wifiscanner.MainActivity$1.onClick(MainActivity.java:44)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.view.View.performClick(View.java:4262)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.view.View$PerformClick.run(View.java:17421)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Handler.handleCallback(Handler.java:615)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Handler.dispatchMessage(Handler.java:92)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Looper.loop(Looper.java:137)
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.app.ActivityThread.main(ActivityThread.java:4947)
05-26 09:41:49.861: E/AndroidRuntime(11186): at java.lang.reflect.Method.invokeNative(Native Method)
05-26 09:41:49.861: E/AndroidRuntime(11186): at java.lang.reflect.Method.invoke(Method.java:511)
05-26 09:41:49.861: E/AndroidRuntime(11186): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
05-26 09:41:49.861: E/AndroidRuntime(11186): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
05-26 09:41:49.861: E/AndroidRuntime(11186): at dalvik.system.NativeStart.main(Native Method)
05-26 09:41:49.941: D/dalvikvm(11186): GC_CONCURRENT freed 203K, 15% free 6966K/8135K, paused 12ms+9ms, total 73ms
05-26 09:42:00.201: I/Process(11186): Sending signal. PID: 11186 SIG: 9
My Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.wifiscanner"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.wifiscanner.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
As soon as I hit the scan button its stop working. If anybody can help me out I would be thankful.

You logcat clearly said
java.lang.SecurityException: WifiService: Neither user 10105 nor current process has android.permission.ACCESS_WIFI_STATE.
05-26 09:41:49.861: E/AndroidRuntime(11186): at android.os.Parcel.readException(Parcel.java:1425)
Add android.permission.ACCESS_WIFI_STATE in your manifest.xml

You need to add the following permissions to the manifest file:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
These need to be added outside the application tag. (Either before or after)
Your manifest file is located in the main folder of the project under the name: AndroidManifest.xml.

Eclipse "Sorry- The application (Appname) has stopped unexpectedly. Please try again"

Hey im a begginer in android coding and ive been following this series on youtube. Whenever I run my project as an android application and go to the emulator to select it, it gives me "Sorry- The application (Appname) has stopped unexpectedly. Please try again" Eclipse doesnt give me any error line to where the problem is and so it is very frustrating.. Ive been looking on the internet for answers to this, but I havent been able to fix it. I think it has something to do with my Manifest. Whenever i run my application there are errors on my LogCat.
My application is a small app that when selected will first open a logo screen for 3 seconds then it will take you to an interface where there are 2 buttons to choose from. Both buttons lead to this thing that edits text.
Ive posted all my code below and please guys keep in mind when you answer that I am a begginer and might not understand some terms. Thank you!
Here is my LogCat when i try to start it
07-20 20:19:17.382: D/dalvikvm(254): GC_EXTERNAL_ALLOC freed 663 objects / 51912 bytes in 177ms
07-20 20:19:19.791: D/AndroidRuntime(254): Shutting down VM
07-20 20:19:19.801: W/dalvikvm(254): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
07-20 20:19:19.811: E/AndroidRuntime(254): FATAL EXCEPTION: main
07-20 20:19:19.811: E/AndroidRuntime(254): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.thepasics/com.example.thepasics.Menu}: java.lang.ClassNotFoundException: com.example.thepasics.Menu in loader dalvik.system.PathClassLoader[/data/app/com.example.thepasics-2.apk]
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.os.Handler.dispatchMessage(Handler.java:99)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.os.Looper.loop(Looper.java:123)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread.main(ActivityThread.java:4627)
07-20 20:19:19.811: E/AndroidRuntime(254): at java.lang.reflect.Method.invokeNative(Native Method)
07-20 20:19:19.811: E/AndroidRuntime(254): at java.lang.reflect.Method.invoke(Method.java:521)
07-20 20:19:19.811: E/AndroidRuntime(254): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
07-20 20:19:19.811: E/AndroidRuntime(254): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
07-20 20:19:19.811: E/AndroidRuntime(254): at dalvik.system.NativeStart.main(Native Method)
07-20 20:19:19.811: E/AndroidRuntime(254): Caused by: java.lang.ClassNotFoundException: com.example.thepasics.Menu in loader dalvik.system.PathClassLoader[/data/app/com.example.thepasics-2.apk]
07-20 20:19:19.811: E/AndroidRuntime(254): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
07-20 20:19:19.811: E/AndroidRuntime(254): at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
07-20 20:19:19.811: E/AndroidRuntime(254): at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
07-20 20:19:19.811: E/AndroidRuntime(254): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
07-20 20:19:19.811: E/AndroidRuntime(254): ... 11 more
My Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.thepasics"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/icon"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.thepasics.Main"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="Menu"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.thePasics.MENU" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name=".TutorialOne"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.thePasics.TUTORIALONE" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
I have 3 Java files which are Menu.java Main.java TutorialOne.java. This one is the Main one
package com.example.thepasics;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
public class Main extends Activity {
MediaPlayer logoMusic;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
logoMusic = MediaPlayer.create(Main.this, R.raw.music);
logoMusic.start();
Thread logoTimer = new Thread(){
public void run(){
try{
sleep(2000);
Intent menuIntent = new Intent("com.example.thePasics.MENU");
startActivity(menuIntent);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{
finish();
}
}
};
logoTimer.start();
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
logoMusic.release();
}
}
This One is the menu.java
package com.example.thepasics;
import android.app.Activity;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class menu extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//Button sound
final MediaPlayer buttonSound = MediaPlayer.create(menu.this, R.raw.buttonsound);
//Setting up button references
Button tut1 = (Button) findViewById(R.id.button1);
Button tut2 = (Button) findViewById(R.id.button2);
tut1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
buttonSound.start();
startActivity(new Intent("com.example.thepasics.TUTORIALONE"));
}
});
tut2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
buttonSound.start();
startActivity(new Intent("com.example.thepasics.TutorialOne"));
}
});
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
}
}
The third one is the TutorialOne.java
import android.app.Activity;
import android.graphics.Typeface;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.TextView;
public class TutorialOne extends Activity implements OnCheckedChangeListener{
TextView textOut;
EditText textIn;
RadioGroup gravityG, styleG;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.tutorial1);
textOut = (TextView) findViewById(R.id.tvChange);
textIn = (EditText) findViewById(R.id.editText1);
gravityG = (RadioGroup) findViewById(R.id.rgGravity);
gravityG.setOnCheckedChangeListener(this);
styleG = (RadioGroup) findViewById(R.id.rgStyle);
styleG.setOnCheckedChangeListener(this);
Button gen = (Button) findViewById(R.id.bGenerate);
gen.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
textOut.setText(textIn.getText());
}
});
}
#Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
// TODO Auto-generated method stub
switch(checkedId){
case R.id.rbLeft:
textOut.setGravity(Gravity.LEFT);
break;
case R.id.rbCenter:
textOut.setGravity(Gravity.CENTER);
break;
case R.id.rbRight:
textOut.setGravity(Gravity.RIGHT);
break;
case R .id.rbNormal:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.NORMAL), Typeface.NORMAL);
break;
case R .id.rbItalic:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.ITALIC), Typeface.ITALIC);
break;
case R .id.rbBold:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD), Typeface.BOLD);
break;
}
}
}
My 3 xml files are splash, tutorial1 and main
this one is main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/backgroundwithoutericapp"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="Choose a function" />
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Button1"
android:textSize="25dp"
android:textStyle="bold"
android:id="#+id/button1"/>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Button2"
android:textSize="25dp"
android:textStyle="bold"
android:id="#+id/button2"/>
</LinearLayout>
second one is splash.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#drawable/background">
</LinearLayout>
third one is tutorial1.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/tutorialonebackground"
android:orientation="vertical" >
<EditText
android:id="#+id/editText1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:weightSum="2" >
<TextView
android:id="#+id/tvStyle"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:gravity="center"
android:text="Style"
android:textSize="25dp"
android:textStyle="bold" />
<TextView
android:id="#+id/tvGravity"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:gravity="center"
android:text="Gravity"
android:textSize="25dp"
android:textStyle="bold" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:weightSum="2" >
<RadioGroup
android:id="#+id/rgStyle"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical" >
<RadioButton
android:id="#+id/rbNormal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Normal" />
<RadioButton
android:id="#+id/rbItalic"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Italic" />
<RadioButton
android:id="#+id/rbBold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Bold" />
</RadioGroup>
<RadioGroup
android:id="#+id/rgGravity"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical" >
<RadioButton
android:id="#+id/rbLeft"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Left" />
<RadioButton
android:id="#+id/rbCenter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Center" />
<RadioButton
android:id="#+id/rbRight"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Right" />
</RadioGroup>
</LinearLayout>
<TextView
android:id="#+id/tvChange"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="Type in Text and Press the Button Below" />
<Button
android:id="#+id/bGenerate"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Generate" />
</LinearLayout>

You have specified wrong class name in manifest.xml
Replace
<activity
android:name="Menu"
android:label="#string/app_name" >
with
<activity
android:name="com.example.thepasics.menu"
android:label="#string/app_name" >

Your Manifest and menu activity don't match. Your manifest has
<activity
android:name="Menu" ...
which first of all isn't a valid name. It could be either android:name=".Menu" to refer to com.com.example.thepasics.Menu or you could use the fully qualified name (as you did for com.example.thepasics.Main).
In addition, your class is named menu, not Menu - remember it is case sensitive. Java convention has class names starting with a capital letter, so it should probably be corrected to Menu.

Your Menu class is actually called "menu" and not "MENU".
public class menu extends Activity{
Try changing "com.example.thePasics.MENU" to "com.example.thePasics.menu" throughout your app.

I only have looked into your Logcat:
07-20 20:19:19.801: W/dalvikvm(254): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
07-20 20:19:19.811: E/AndroidRuntime(254): FATAL EXCEPTION: main
07-20 20:19:19.811: E/AndroidRuntime(254): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.thepasics/com.example.thepasics.Menu}: java.lang.ClassNotFoundException: com.example.thepasics.Menu in loader dalvik.system.PathClassLoader[/data/app/com.example.thepasics-2.apk]
Your app is crashing becuase your com.example.thepasics.Menu is not being found, and also use android:name=".Menu" instead of android:name="Menu".

whenever application is executed it is displayed as blank in android emulator

Below i have pasted copy of my java,xml and logcat of the application.
Here goes my java code
package my.example.myproject;
import my.example.myproject.util.SystemUiHider;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
/**
* An example full-screen activity that shows and hides the system UI (i.e.
* status bar and navigation/system bar) with user interaction.
*
* #see SystemUiHider
*/
public class FullscreenActivity extends Activity {
/**
* Whether or not the system UI should be auto-hidden after
* {#link #AUTO_HIDE_DELAY_MILLIS} milliseconds.
*/
private static final boolean AUTO_HIDE = true;
/**
* If {#link #AUTO_HIDE} is set, the number of milliseconds to wait after
* user interaction before hiding the system UI.
*/
private static final int AUTO_HIDE_DELAY_MILLIS = 3000;
/**
* If set, will toggle the system UI visibility upon interaction. Otherwise,
* will show the system UI visibility upon interaction.
*/
private static final boolean TOGGLE_ON_CLICK = true;
/**
* The flags to pass to {#link SystemUiHider#getInstance}.
*/
private static final int HIDER_FLAGS = SystemUiHider.FLAG_HIDE_NAVIGATION;
/**
* The instance of the {#link SystemUiHider} for this activity.
*/
private SystemUiHider mSystemUiHider;
Button iol,help,about;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fullscreen);
final View controlsView = findViewById(R.id.fullscreen_content_controls);
iol = (Button)findViewById(R.id.iolCalculation);
help = (Button)findViewById(R.id.sHelp);
about = (Button)findViewById(R.id.sAbout);
Thread iolthread=new Thread(){
public void run(){
try{
iol.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
setContentView(R.layout.selection);
}
});
Intent iolIntent=new Intent(FullscreenActivity.this,Selection.class);
startActivity(iolIntent);
}
finally{
finish();
}
}
};
iolthread.start();
// Set up an instance of SystemUiHider to control the system UI for
// this activity.
mSystemUiHider = SystemUiHider.getInstance(this, controlsView,
HIDER_FLAGS);
mSystemUiHider.setup();
mSystemUiHider
.setOnVisibilityChangeListener(new SystemUiHider.OnVisibilityChangeListener() {
// Cached values.
int mControlsHeight;
int mShortAnimTime;
#Override
#TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
public void onVisibilityChange(boolean visible) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
// If the ViewPropertyAnimator API is available
// (Honeycomb MR2 and later), use it to animate the
// in-layout UI controls at the bottom of the
// screen.
if (mControlsHeight == 0) {
mControlsHeight = controlsView.getHeight();
}
if (mShortAnimTime == 0) {
mShortAnimTime = getResources().getInteger(
android.R.integer.config_shortAnimTime);
}
controlsView
.animate()
.translationY(visible ? 0 : mControlsHeight)
.setDuration(mShortAnimTime);
} else {
// If the ViewPropertyAnimator APIs aren't
// available, simply show or hide the in-layout UI
// controls.
controlsView.setVisibility(visible ? View.VISIBLE
: View.GONE);
}
if (visible && AUTO_HIDE) {
// Schedule a hide().
delayedHide(AUTO_HIDE_DELAY_MILLIS);
}
}
});
// Set up the user interaction to manually show or hide the system UI.
controlsView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (TOGGLE_ON_CLICK) {
mSystemUiHider.toggle();
} else {
mSystemUiHider.show();
}
}
});
// Upon interacting with UI controls, delay any scheduled hide()
// operations to prevent the jarring behavior of controls going away
// while interacting with the UI.
}
#Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
// Trigger the initial hide() shortly after the activity has been
// created, to briefly hint to the user that UI controls
// are available.
delayedHide(100);
}
/**
* Touch listener to use for in-layout UI controls to delay hiding the
* system UI. This is to prevent the jarring behavior of controls going away
* while interacting with activity UI.
*/
View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent motionEvent) {
if (AUTO_HIDE) {
delayedHide(AUTO_HIDE_DELAY_MILLIS);
}
return false;
}
};
Handler mHideHandler = new Handler();
Runnable mHideRunnable = new Runnable() {
#Override
public void run() {
mSystemUiHider.hide();
}
};
/**
* Schedules a call to hide() in [delay] milliseconds, canceling any
* previously scheduled calls.
*/
private void delayedHide(int delayMillis) {
mHideHandler.removeCallbacks(mHideRunnable);
mHideHandler.postDelayed(mHideRunnable, delayMillis);
}
}
XML
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black"
tools:context=".FullscreenActivity"
android:id="#+id/frame_layout">
<LinearLayout
android:id="#+id/fullscreen_content_controls"
style="?buttonBarStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center_horizontal"
android:background="#color/black_overlay"
android:orientation="horizontal"
tools:ignore="UselessParent" >
</LinearLayout>
<Button
style="#style/ButtonBarButton"
android:layout_width="222dp"
android:layout_height="62dp"
android:layout_marginLeft="45dp"
android:layout_marginTop="75dp"
android:background="#color/black"
android:paddingLeft="20dp"
android:id="#+id/iolCalculation"
android:text="#string/Button"
android:textColor="#color/WhiteSmoke"
android:textStyle="bold" />
<Button
style="#style/ButtonBarButton"
android:layout_width="222dp"
android:layout_height="62dp"
android:layout_marginLeft="45dp"
android:id="#+id/sHelp"
android:layout_marginTop="139dp"
android:background="#color/Black"
android:gravity="center"
android:paddingLeft="10dp"
android:text="#string/Button1"
android:textColor="#color/WhiteSmoke"
android:textStyle="bold" />
<Button
style="#style/ButtonBarButton"
android:layout_width="222dp"
android:layout_height="62dp"
android:id="#+id/sAbout"
android:layout_marginLeft="45dp"
android:layout_marginTop="203dp"
android:background="#color/Black"
android:paddingLeft="10dp"
android:text="#string/Button2"
android:textColor="#color/WhiteSmoke"
android:textStyle="bold" >
</Button>
</FrameLayout>
logcat
12-16 10:48:26.975: E/Trace(767): error opening trace file: No such file or directory (2)
12-16 10:51:38.199: E/AndroidRuntime(767): FATAL EXCEPTION: main
12-16 10:51:38.199: E/AndroidRuntime(767): java.lang.NullPointerException
12-16 10:51:38.199: E/AndroidRuntime(767): at com.android.internal.widget.ActionBarView$3.onClick(ActionBarView.java:168)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.view.View.performClick(View.java:4202)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.view.View$PerformClick.run(View.java:17340)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.os.Handler.handleCallback(Handler.java:725)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.os.Handler.dispatchMessage(Handler.java:92)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.os.Looper.loop(Looper.java:137)
12-16 10:51:38.199: E/AndroidRuntime(767): at android.app.ActivityThread.main(ActivityThread.java:5039)
12-16 10:51:38.199: E/AndroidRuntime(767): at java.lang.reflect.Method.invokeNative(Native Method)
12-16 10:51:38.199: E/AndroidRuntime(767): at java.lang.reflect.Method.invoke(Method.java:511)
12-16 10:51:38.199: E/AndroidRuntime(767): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
12-16 10:51:38.199: E/AndroidRuntime(767): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
12-16 10:51:38.199: E/AndroidRuntime(767): at dalvik.system.NativeStart.main(Native Method)
i have tried every possible solution in stackoverflow but in vain.help me. I think mostly there is a problem in xml to java display content.Also do i need to put in id for every layout in xml and how does the java code detect the layout to be displayed
here goes my selection java code and xml
package com.example.iolcalci;
import android.app.Activity;
import android.os.Bundle;
public class Selection extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.selective);
}
}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black"
android:orientation="vertical" >
<Spinner
android:id="#+id/formulae"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp"
android:background="#color/LightSkyBlue"
android:prompt="#string/prompt"
android:entries="#array/formulas" />
<TextView
android:id="#+id/k2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/k1"
android:layout_below="#+id/k1"
android:layout_marginTop="38dp"
android:text="#string/K2"
android:textColor="#color/White"
android:textSize="25sp" />
<TextView
android:id="#+id/al_const"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/al"
android:layout_below="#+id/al"
android:layout_marginTop="44dp"
android:text="#string/Rx"
android:textColor="#color/White"
android:textSize="20sp" />
<TextView
android:id="#+id/al"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/k2"
android:layout_below="#+id/k2"
android:layout_marginTop="38dp"
android:text="#string/AL"
android:textColor="#color/White"
android:textSize="25sp" />
<EditText
android:id="#+id/k2_editText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/al"
android:layout_alignRight="#+id/al_editText"
android:layout_alignTop="#+id/k2"
android:layout_marginLeft="120dp"
android:background="#color/black"
android:ems="10"
android:inputType="numberDecimal"
android:textColorLink="#color/white" />
<EditText
android:id="#+id/al_editText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/formulae"
android:layout_alignTop="#+id/al"
android:layout_marginLeft="120dp"
android:ems="10"
android:inputType="numberDecimal" />
<EditText
android:id="#+id/al_const_editText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/al_const"
android:layout_alignRight="#+id/al_editText"
android:layout_marginLeft="120dp"
android:ems="10"
android:inputType="numberDecimal" />
<Button
android:id="#+id/result"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:background="#color/LightSkyBlue"
android:text="#string/Result" />
<EditText
android:id="#+id/k1_editText"
android:layout_width="wrap_content"
android:layout_height="37dp"
android:layout_alignLeft="#+id/k2_editText"
android:layout_alignRight="#+id/formulae"
android:layout_below="#+id/formulae"
android:layout_marginTop="30dp"
android:background="#color/black"
android:ems="10"
android:inputType="numberDecimal"
android:textColorLink="#color/White" />
<TextView
android:id="#+id/k1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/k1_editText"
android:layout_alignParentLeft="true"
android:layout_marginLeft="27dp"
android:text="#string/K1"
android:textColor="#color/white"
android:textSize="25sp" />
</RelativeLayout>
THE NEW LOGCAT
12-21 10:44:50.419: W/Trace(766): Unexpected value from nativeGetEnabledTags: 0
12-21 10:44:50.573: W/Trace(766): Unexpected value from nativeGetEnabledTags: 0
12-21 10:44:50.573: W/Trace(766): Unexpected value from nativeGetEnabledTags: 0
12-21 10:44:50.923: D/AndroidRuntime(766): Shutting down VM
12-21 10:44:50.923: W/dalvikvm(766): threadid=1: thread exiting with uncaught exception (group=0x40a70930)
12-21 10:44:50.933: E/AndroidRuntime(766): FATAL EXCEPTION: main
12-21 10:44:50.933: E/AndroidRuntime(766): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.iolcalci/com.example.iolcalci.MainActivity}: java.lang.NullPointerException
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread.access$600(ActivityThread.java:141)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.os.Handler.dispatchMessage(Handler.java:99)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.os.Looper.loop(Looper.java:137)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread.main(ActivityThread.java:5039)
12-21 10:44:50.933: E/AndroidRuntime(766): at java.lang.reflect.Method.invokeNative(Native Method)
12-21 10:44:50.933: E/AndroidRuntime(766): at java.lang.reflect.Method.invoke(Method.java:511)
12-21 10:44:50.933: E/AndroidRuntime(766): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
12-21 10:44:50.933: E/AndroidRuntime(766): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
12-21 10:44:50.933: E/AndroidRuntime(766): at dalvik.system.NativeStart.main(Native Method)
12-21 10:44:50.933: E/AndroidRuntime(766): Caused by: java.lang.NullPointerException
12-21 10:44:50.933: E/AndroidRuntime(766): at com.example.iolcalci.MainActivity.onCreate(MainActivity.java:23)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.Activity.performCreate(Activity.java:5104)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
12-21 10:44:50.933: E/AndroidRuntime(766): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
12-21 10:44:50.933: E/AndroidRuntime(766): ... 11 more
Manifest file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.iolcalci"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.iolcalci.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="Selection"
android:exported="false"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="#string/app_name">
<intent-filter>
<action android:name="com.example.iolcalci.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>

Judging from your code I'm going to go with the conjecture that this line is causing the error:
setContentView(R.id.selection);
There's no need to change the contentView of the activity from which you're calling the "selection" activity. You should read up on intents. I'm assuming that when the button is clicked, you want the new activity and it's content to pop up. For that, do this :
try{
iol.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent iolIntent=new Intent(FullscreenActivity.this,Selection.class);
startActivity(iolIntent);
}
});
}
Also set your button's layout width and layout height to "wrap_content". Definite measurements won't work well because there are many resolutions possible.
android:layout_height="wrap_content"
android:layout_width="wrap_content"
In case of more errors, post the new logcat, please.
I found this in your selection.java:
setContentView(R.layout.selective);
This means you should have a selective.xml file in your res/layout/ folder.
This selective.xml file should contain a definition of EditText.
Example,
<EditText
android:id="#+id/k1_editText"
android:layout_width="wrap_content"
android:layout_height="37dp"
android:layout_alignLeft="#+id/k2_editText"
android:layout_alignRight="#+id/formulae"
android:layout_below="#+id/formulae"
android:layout_marginTop="30dp"
android:background="#color/black"
android:ems="10"
android:inputType="numberDecimal"
android:textColorLink="#color/White" />
You need to reference this in the activity file with this piece of code:
EditText ed=new EditText findViewById(R.id.k2_editText);
Now the EditText field will be displayed.
If you want to make your EditText object global, declare it in the class and then initialize it after setting content view. Like this,
public class Selection extends Activity {
EditText ed;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.selective);
EditText ed=new EditText findViewById(R.id.k2_editText);
}
Make sure you always initialize a widget object AFTER the creation of the activity and setting content view, because otherwise the compiler is going to have to initialize something which hasn't been referenced yet. The layout file is referenced only after setting content view. Only after setting the layout file can you initialize objects to whatever is present inside the layout file.
If you like the answer, do vote it up.