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.com.process stopped unexpectedly in Android emulator and mobile

I am trying to make a simple android app that will add two numbers and display the output.However, I am getting the following error continuously.
"calculator.com.process stopped unexpectedly"
I used API 10 for rendering layout and API 17 as compiler and Target SDK.
Could post the code finally after all these trouble.
This is the code of main_activity.java
package com.example.calculator;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
EditText txtNum1;
EditText txtNum2;
TextView Display;
Button bCal;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txtNum1=(EditText) findViewById(R.id.Num1);
txtNum1=(EditText) findViewById(R.id.Num2);
Display=(TextView)findViewById(R.id.tvDisplay);
bCal=(Button)findViewById(R.id.bAdd);
bCal.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View Tawfiq) {
// TODO Auto-generated method stub
double x=Double.parseDouble(txtNum1.getText().toString());
double y=Double.parseDouble(txtNum2.getText().toString());
double total=x+y;
Display.setText("Sum is"+total);
}
});
}
#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;
}
#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.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
The xml code:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/bAdd"
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.calculator.MainActivity" >
<EditText
android:id="#+id/Num1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="50dp"
android:ems="10"
android:inputType="numberDecimal" >
<requestFocus />
</EditText>
<EditText
android:id="#+id/Num2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/Num1"
android:layout_below="#+id/Num1"
android:layout_marginTop="33dp"
android:ems="10"
android:inputType="numberDecimal" />
<Button
android:id="#+id/bAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/tvDisplay"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:text="Button" />
<TextView
android:id="#+id/tvDisplay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/Num2"
android:layout_centerHorizontal="true"
android:layout_marginTop="30dp"
android:text="Sum"
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
This is the logcat.
01-24 16:06:39.840: D/AndroidRuntime(1130): Shutting down VM
01-24 16:06:39.870: W/dalvikvm(1130): threadid=1: thread exiting with uncaught exception (group=0xb60164f0)
01-24 16:06:39.950: E/AndroidRuntime(1130): FATAL EXCEPTION: main
01-24 16:06:39.950: E/AndroidRuntime(1130): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.calculator/com.example.calculator.MainActivity}: java.lang.ClassCastException: android.widget.RelativeLayout
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.os.Handler.dispatchMessage(Handler.java:99)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.os.Looper.loop(Looper.java:130)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread.main(ActivityThread.java:3683)
01-24 16:06:39.950: E/AndroidRuntime(1130): at java.lang.reflect.Method.invokeNative(Native Method)
01-24 16:06:39.950: E/AndroidRuntime(1130): at java.lang.reflect.Method.invoke(Method.java:507)
01-24 16:06:39.950: E/AndroidRuntime(1130): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
01-24 16:06:39.950: E/AndroidRuntime(1130): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
01-24 16:06:39.950: E/AndroidRuntime(1130): at dalvik.system.NativeStart.main(Native Method)
01-24 16:06:39.950: E/AndroidRuntime(1130): Caused by: java.lang.ClassCastException: android.widget.RelativeLayout
01-24 16:06:39.950: E/AndroidRuntime(1130): at com.example.calculator.MainActivity.onCreate(MainActivity.java:27)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-24 16:06:39.950: E/AndroidRuntime(1130): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
01-24 16:06:39.950: E/AndroidRuntime(1130): ... 11 more

You are having problem at line no-27
Caused by: java.lang.ClassCastException: android.widget.RelativeLayout
01-24 16:06:39.950: E/AndroidRuntime(1130): at com.example.calculator.MainActivity.onCreate(MainActivity.java:27)
Change the relativeLayouts Id in the xml file.
It should not be same as for the add button.
android:id="#+id/relativeLayout"
Change it as above.
Two id in the same layout cannot be same.
Your add button and the relative layout is having the same id,.
And during the findViewById(), relative layout is being caste in the Button.
That's why class cast exception is coming.
Edit:
I compiled your code:-
the next mistake you have made is-
txtNum1=(EditText) findViewById(R.id.Num2);
It should be
txtNum2=(EditText) findViewById(R.id.Num2);
Mistake-You are not assigning the reference to the second edittext.

Display random month from a button click on android?

I am trying to create an app that lets the user click a button and it will display a random month. I have created a string array in my strings.xml file. Bellow is my main.java, strings.xml and activity.xml. I try to run the app and it just force closes.
package com.example.datebutton;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.graphics.Color;
public class Main extends Activity
{
Button btn;
#Override
public void onCreate(Bundle b)
{
super.onCreate(b);
setContentView(R.layout.activity_main);
btn = (Button) findViewById(R.id.btn1);
final String[] months = getResources().getStringArray(R.array.Months);
final TextView tv =(TextView)findViewById(R.id.text1);
btn.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
int rand = (int) (Math.random() * 12);
tv.setText(months[rand]);
}
});
}
}
here is my activity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:id="#+id/btn1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="updateMonth"
android:text="#string/app_name" />
<TextView
android:id="#+id/text1"
android:layout_width="68dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center_vertical"
android:text="#array/Months" />
</LinearLayout>
here is my strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">DateButton</string>
<string-array name="Months">
<item>January</item>
<item>Feburary</item>
<item>March</item>
<item>April</item>
<item>May</item>
<item>June</item>
<item>July</item>
<item>August</item>
<item>September</item>
<item>October</item>
<item>November</item>
<item>December</item>
</string-array>
</resources>
I'm still getting errors and the app still says unfortunately your app closed. The logcat is below.
09-11 16:55:17.472: W/Resources(1638): Converting to string: TypedValue{t=0x1/d=0x7f0c0000 a=-1 r=0x7f0c0000}
09-11 16:55:17.512: D/AndroidRuntime(1638): Shutting down VM
09-11 16:55:17.512: W/dalvikvm(1638): threadid=1: thread exiting with uncaught exception (group=0xb3a8fba8)
09-11 16:55:17.532: E/AndroidRuntime(1638): FATAL EXCEPTION: main
09-11 16:55:17.532: E/AndroidRuntime(1638): Process: com.example.datebutton, PID: 1638
09-11 16:55:17.532: E/AndroidRuntime(1638): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.datebutton/com.example.datebutton.Main}: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.Button
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread.access$800(ActivityThread.java:135)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.os.Handler.dispatchMessage(Handler.java:102)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.os.Looper.loop(Looper.java:136)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread.main(ActivityThread.java:5017)
09-11 16:55:17.532: E/AndroidRuntime(1638): at java.lang.reflect.Method.invokeNative(Native Method)
09-11 16:55:17.532: E/AndroidRuntime(1638): at java.lang.reflect.Method.invoke(Method.java:515)
09-11 16:55:17.532: E/AndroidRuntime(1638): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
09-11 16:55:17.532: E/AndroidRuntime(1638): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
09-11 16:55:17.532: E/AndroidRuntime(1638): at dalvik.system.NativeStart.main(Native Method)
09-11 16:55:17.532: E/AndroidRuntime(1638): Caused by: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.Button
09-11 16:55:17.532: E/AndroidRuntime(1638): at com.example.datebutton.Main.onCreate(Main.java:24)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.Activity.performCreate(Activity.java:5231)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
09-11 16:55:17.532: E/AndroidRuntime(1638): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
09-11 16:55:17.532: E/AndroidRuntime(1638): ... 11 more

You forgot to add the line: setContentView(R.layout.activity); before trying to instantiate your button object btn.

To use layout in you Activity you have to connect them both together. Below is how your code should look like:
#Override
public void onCreate(Bundle b) {
super.onCreate(b);
setContentView(R.layout.activity);
btn = (Button) findViewById(R.id.btn1);
final String[] months = getResources().getStringArray(R.array.Months);
final TextView tv =(TextView)findViewById(R.id.text1);
btn.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
int r, g, b;
int rand = (int) (Math.random() * 12);
tv.setText(months[rand]);
}
});
}

ADT simple app - fatal exception [duplicate]

This question already has answers here:
Unfortunately MyApp has stopped. How can I solve this?
(23 answers)
Closed 8 years ago.
I have just started out with Android and Java, and i have just made a simple app with a couple of textviews, a button and a edittext.
When i run the app i get an error saying the: Unfortunately, FirstApp has stopped.
I am familiar with programming, and wonder if i miss some library, or if ADT is misconfigured.
I have tried to clean and rebuild, to right click the project in the Package explorer and Android Tools -> Add support library, restarted the emulator, restarted ADT and restarted the computer. Cant figure out what does this.
Can any of you see something wrong here?
MainActivity.java imports
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.*;
import android.os.Build;
MainActivity.java
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btnCalc = (Button)findViewById(R.id.btnCalc);
btnCalc.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
EditText number = (EditText)findViewById(R.id.num);
TextView display = (TextView)findViewById(R.id.display);
double num = Double.parseDouble(number.getText().toString());
num = num * 5;
display.setText(num + "");
}
});
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
}
#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.danlevi.testproject.MainActivity$PlaceholderFragment" >
<TextView
android:id="#+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="#string/lblTitle" />
<EditText
android:id="#+id/num"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="15dp"
android:ems="10"
android:inputType="numberDecimal|numberSigned" >
<requestFocus />
</EditText>
<Button
android:id="#+id/btnCalc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/num"
android:layout_centerHorizontal="true"
android:layout_marginTop="14dp"
android:text="#string/btnCalc" />
<TextView
android:id="#+id/display"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/btnCalc"
android:layout_marginTop="16dp" />
</RelativeLayout>
Console
[2014-05-16 18:33:16 - TestProject] Dx
trouble writing output: already prepared
[2014-05-16 18:33:17 - TestProject] ------------------------------
[2014-05-16 18:33:17 - TestProject] Android Launch!
[2014-05-16 18:33:17 - TestProject] adb is running normally.
[2014-05-16 18:33:17 - TestProject] Performing com.danlevi.testproject.MainActivity activity launch
[2014-05-16 18:33:17 - TestProject] Automatic Target Mode: using existing emulator 'emulator-5554' running compatible AVD 'Android'
[2014-05-16 18:33:17 - TestProject] Uploading TestProject.apk onto device 'emulator-5554'
[2014-05-16 18:33:18 - TestProject] Installing TestProject.apk...
[2014-05-16 18:33:30 - TestProject] Success!
[2014-05-16 18:33:30 - TestProject] Starting activity com.danlevi.testproject.MainActivity on device emulator-5554
[2014-05-16 18:33:33 - TestProject] ActivityManager: Starting: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] cmp=com.danlevi.testproject/.MainActivity }
LogCat
05-16 12:33:37.412: D/AndroidRuntime(1579): Shutting down VM
05-16 12:33:37.412: W/dalvikvm(1579): threadid=1: thread exiting with uncaught exception (group=0xb2b08ba8)
05-16 12:33:37.432: E/AndroidRuntime(1579): FATAL EXCEPTION: main
05-16 12:33:37.432: E/AndroidRuntime(1579): Process: com.danlevi.testproject, PID: 1579
05-16 12:33:37.432: E/AndroidRuntime(1579): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.danlevi.testproject/com.danlevi.testproject.MainActivity}: java.lang.NullPointerException
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.os.Handler.dispatchMessage(Handler.java:102)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.os.Looper.loop(Looper.java:136)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread.main(ActivityThread.java:5017)
05-16 12:33:37.432: E/AndroidRuntime(1579): at java.lang.reflect.Method.invokeNative(Native Method)
05-16 12:33:37.432: E/AndroidRuntime(1579): at java.lang.reflect.Method.invoke(Method.java:515)
05-16 12:33:37.432: E/AndroidRuntime(1579): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-16 12:33:37.432: E/AndroidRuntime(1579): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-16 12:33:37.432: E/AndroidRuntime(1579): at dalvik.system.NativeStart.main(Native Method)
05-16 12:33:37.432: E/AndroidRuntime(1579): Caused by: java.lang.NullPointerException
05-16 12:33:37.432: E/AndroidRuntime(1579): at com.danlevi.testproject.MainActivity.onCreate(MainActivity.java:25)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.Activity.performCreate(Activity.java:5231)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
05-16 12:33:37.432: E/AndroidRuntime(1579): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
05-16 12:33:37.432: E/AndroidRuntime(1579): ... 11 more
05-16 12:33:44.352: I/Process(1579): Sending signal. PID: 1579 SIG: 9

This is because findViewById() searches in the activity_main layout, while the button is located in the fragment's layout fragment_main.
Move that piece of code in the onCreateView() method of the fragment:
//...
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
Button buttonClick = (Button)rootView.findViewById(R.id.button);
buttonClick.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
onButtonClick((Button) view);
}
});
Notice that now you access it through rootView view:
Button buttonClick = (Button)rootView.findViewById(R.id.button);
otherwise you would get again NullPointerException.
In your code, move
changer = (Button) findViewById(R.id.change1);
changeme = (TextView) findViewById (R.id.changeme1);
changer.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
changeme.setText("Changed");
}
});
to onCreateView() method of the fragment

my android app error unfortunately app has stopped

I am new to Android.
I've just started to build my first Android app and have been struggling with this errorfor the past 2 days.
Finding no solution I had to come here.
Error:
Unfortunately "app name" has stopped
This is main activity layout:
<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=".MainActivity" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:text="TextView" />
</RelativeLayout>
This is another layout:
<?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">
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"></ListView>
</LinearLayout>
logcat error
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.listview/com.example.listview.MainActivity}: java.lang.NullPointerException
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread.access$700(ActivityThread.java:135)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.os.Handler.dispatchMessage(Handler.java:102)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.os.Looper.loop(Looper.java:137)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread.main(ActivityThread.java:4998)
03-25 12:01:29.772: E/AndroidRuntime(1314): at java.lang.reflect.Method.invokeNative(Native Method)
03-25 12:01:29.772: E/AndroidRuntime(1314): at java.lang.reflect.Method.invoke(Method.java:515)
03-25 12:01:29.772: E/AndroidRuntime(1314): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
03-25 12:01:29.772: E/AndroidRuntime(1314): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
03-25 12:01:29.772: E/AndroidRuntime(1314): at dalvik.system.NativeStart.main(Native Method)
03-25 12:01:29.772: E/AndroidRuntime(1314): Caused by: java.lang.NullPointerException
03-25 12:01:29.772: E/AndroidRuntime(1314): at com.example.listview.MainActivity.onCreate(MainActivity.java:36)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.Activity.performCreate(Activity.java:5243)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
03-25 12:01:29.772: E/AndroidRuntime(1314): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140)
03-25 12:01:29.772: E/AndroidRuntime(1314): ... 11 more
03-25 12:01:35.622: I/Process(1314): Sending signal. PID: 1314 SIG: 9
03-25 12:11:56.522: D/AndroidRuntime(1378): Shutting down VM
03-25 12:11:56.522: W/dalvikvm(1378): threadid=1: thread exiting with uncaught exception (group=0xb3adbb90)
03-25 12:11:56.542: E/AndroidRuntime(1378): FATAL EXCEPTION: main
03-25 12:11:56.542: E/AndroidRuntime(1378): Process: com.example.listview, PID: 1378
03-25 12:11:56.542: E/AndroidRuntime(1378): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.listview/com.example.listview.MainActivity}: java.lang.NullPointerException
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread.access$700(ActivityThread.java:135)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.os.Handler.dispatchMessage(Handler.java:102)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.os.Looper.loop(Looper.java:137)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread.main(ActivityThread.java:4998)
03-25 12:11:56.542: E/AndroidRuntime(1378): at java.lang.reflect.Method.invokeNative(Native Method)
03-25 12:11:56.542: E/AndroidRuntime(1378): at java.lang.reflect.Method.invoke(Method.java:515)
03-25 12:11:56.542: E/AndroidRuntime(1378): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
03-25 12:11:56.542: E/AndroidRuntime(1378): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
03-25 12:11:56.542: E/AndroidRuntime(1378): at dalvik.system.NativeStart.main(Native Method)
03-25 12:11:56.542: E/AndroidRuntime(1378): Caused by: java.lang.NullPointerException
03-25 12:11:56.542: E/AndroidRuntime(1378): at com.example.listview.MainActivity.onCreate(MainActivity.java:36)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.Activity.performCreate(Activity.java:5243)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
03-25 12:11:56.542: E/AndroidRuntime(1378): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140)
03-25 12:11:56.542: E/AndroidRuntime(1378): ... 11 more
main activity code
package com.example.listview;
import java.util.ArrayList;
import java.util.Arrays;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView lst = (ListView)findViewById(R.id.listView1);
//ListView mainListView = null;
String[] test = new String[] { "Mercury", "Venus", "Earth", "Mars",
"Jupiter", "Saturn", "Uranus", "Neptune"};
ArrayList<String> planetList = new ArrayList<String>();
planetList.addAll( Arrays.asList(test) );
ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(this, R.layout.simplerow, planetList);
// Add more planets. If you passed a String[] instead of a List<String>
// into the ArrayAdapter constructor, you must not add more items.
// Otherwise an exception will occur.
listAdapter.add( "Ceres" );
listAdapter.add( "Pluto" );
listAdapter.add( "Haumea" );
listAdapter.add( "Makemake" );
listAdapter.add( "Eris" );
// Set the ArrayAdapter as the ListView's adapter.
lst.setAdapter( listAdapter );
}
#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;
}
}

Your listview is not contained in the activity's layout so when you call it it gives you a null pointer exception. you could put the listview inside the main activity's layout.
<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=".MainActivity" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:text="TextView" />
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"></ListView>
</RelativeLayout>

Line 36 is:
lst.setAdapter( listAdapter );
Means that lst is probably null.
ListView lst = (ListView)findViewById(R.id.listView1); //NULL
Failed to find the view, because you load main_activity layout, which does not have a ListView with id=listView1.
Probably you need to load another layout, which it contains.

ListView lst = (ListView)findViewById(R.id.listView1); return null because you don't use the right content in setContentView(R.layout.activity_main);. You have two options:
Use a include to put a layout inside another:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
... >
<TextView
... />
<include android:layout="#layout\my_layout_listview" />
</RelativeLayout>
Or set the other layout which contains your ListView in:
setContentView(R.layout.my_layout_listview);

Why does my app "unfortunately stop". All this I want is some simple buttons

This is my very first app. All I need is five buttons, two that call certain phone numbers (only have created one so far) and three buttons that take the user to a certain URL. I have no errors or warnings or any direction on how to navigate the LogCat.
LogCat:
10-08 14:41:40.716: D/AndroidRuntime(793): Shutting down VM
10-08 14:41:40.716: W/dalvikvm(793): threadid=1: thread exiting with uncaught exception (group=0x41465700)
10-08 14:41:40.777: E/AndroidRuntime(793): FATAL EXCEPTION: main
10-08 14:41:40.777: E/AndroidRuntime(793): java.lang.RuntimeException: Unable to start activity ComponentInfo{acps.mhs/acps.mhs.MainActivity}: java.lang.NullPointerException
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread.access$600(ActivityThread.java:141)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.os.Handler.dispatchMessage(Handler.java:99)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.os.Looper.loop(Looper.java:137)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread.main(ActivityThread.java:5103)
10-08 14:41:40.777: E/AndroidRuntime(793): at java.lang.reflect.Method.invokeNative(Native Method)
10-08 14:41:40.777: E/AndroidRuntime(793): at java.lang.reflect.Method.invoke(Method.java:525)
10-08 14:41:40.777: E/AndroidRuntime(793): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
10-08 14:41:40.777: E/AndroidRuntime(793): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-08 14:41:40.777: E/AndroidRuntime(793): at dalvik.system.NativeStart.main(Native Method)
10-08 14:41:40.777: E/AndroidRuntime(793): Caused by: java.lang.NullPointerException
10-08 14:41:40.777: E/AndroidRuntime(793): at acps.mhs.MainActivity.onCreate(MainActivity.java:25)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.Activity.performCreate(Activity.java:5133)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-08 14:41:40.777: E/AndroidRuntime(793): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
10-08 14:41:40.777: E/AndroidRuntime(793): ... 11 more
10-08 14:42:19.696: I/Process(793): Sending signal. PID: 793 SIG: 9
Mainactivity.java
package acps.mhs;
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
public class MainActivity extends Activity implements View.OnClickListener {
Button mhshome, pp, mhsdir, cmhs;
#Override
public void onCreate(Bundle bundle) {
super.onCreate(bundle);
mhshome = (Button) findViewById(R.id.mhshome);
pp = (Button) findViewById(R.id.pp);
mhsdir = (Button) findViewById(R.id.mhsdir);
cmhs = (Button) findViewById(R.id.cmhs);
mhshome.setOnClickListener(this);
pp.setOnClickListener(this);
mhsdir.setOnClickListener(this);
cmhs.setOnClickListener(this);
}
#Override
public void onClick(View v) {
switch(v.getId()) {
case R.id.mhshome:
Uri uri = Uri.parse("http://www2.k12albemarle.org/school/mohs/Pages/default.aspx");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
break;
case R.id.pp:
Uri uri2 = Uri.parse("http://www2.k12albemarle.org/school/MOHS/Pages/Directory.aspx");
Intent intent2 = new Intent(Intent.ACTION_VIEW, uri2);
startActivity(intent2);
break;
case R.id.mhsdir:
Uri uri3 = Uri.parse("http://www2.k12albemarle.org/school/MOHS/Pages/Directory.aspx");
Intent intent3 = new Intent(Intent.ACTION_VIEW, uri3);
startActivity(intent3);
break;
case R.id.cmhs:
Intent callIntent = new Intent(Intent.ACTION_CALL);
callIntent.setData(Uri.parse("tel:1234567890"));
startActivity(callIntent);
break;
}
}
#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;
}
}
activity_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=".MainActivity" >
<Button
android:id="#+id/pp"
style="#style/AppBaseTheme"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/mhshome"
android:layout_centerHorizontal="true"
android:layout_marginTop="16dp"
android:text="#string/pp"/>
<Button
android:id="#+id/mhshome"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="26dp"
android:onClick="onClick"
android:text="#string/mhshome" />
<Button
android:id="#+id/mhsdir"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/pp"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:text="#string/mhsdir" />
<Button
android:id="#+id/cmhs"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/mhsdir"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:text="#string/callmhs" />
</RelativeLayout>
Its gonna be something incredibly simple I'm certain. Please point me in the right direction.

You need to call setContentView(R.layout.activity_main) :) That's why findViewById is returning null on your views.

You are not setting your layout.
Call setContentView(layout) in your onCreate() method.