We Keep Coding

Why intent makes my application crashed?

I just want to ask you why using intent makes my system crashed? I've used same codes before and it works, then when I use it again now it won't. What do you think the problem guys?
MANIFEST
<?xml version="1.0" encoding="utf-8"?>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<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=".Login"
android:label="#string/title_activity_login" >
</activity>
</application>
MainActivity
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void okay(View view) {
Intent i = new Intent(this, Login.class);
startActivity(i);
2nd Activity (If I clicked the main activity, I just want this activity pop)
public class Login extends ActionBarActivity {
ListView listView;
ArrayAdapter<String> adapter;
String[] grocery_categories = {"Beverages", "Bakery", "Canned Goods", "Condiments", "Dairy", "Snacks", "Frozen Foods",
"Meat", "Produce", "Cleaners", "Paper Goods", "Personal Care", "Others"};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
listView = (ListView) findViewById(R.id.list_view);
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, grocery_categories);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> listView, View view, int position, long id) {
String grocery = (String) listView.getAdapter().getItem(position);
Intent intent = new Intent(listView.getContext(),Login.class);
listView.getContext().startActivity(intent);
//or create other intents here
}
});
}
XML of MainActivity
<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" tools:context=".MainActivity"
android:id="#+id/rl_main_activity">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/mobile_grocery_bckgrnd"
android:src="#drawable/mobile_grocery"
android:scaleType="centerCrop"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="MOBILE GROCERY"
android:id="#+id/mobile_grocery_app"
android:textSize="45dp"
android:textColor="#000000"
android:gravity="center"
android:textStyle="bold|italic"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Application"
android:id="#+id/application"
android:textColor="#000000"
android:textSize="25dp"
android:layout_below="#+id/mobile_grocery_app"
android:layout_centerHorizontal="true" />
<EditText
android:layout_width="200dp"
android:layout_height="wrap_content"
android:id="#+id/username"
android:layout_alignParentBottom="true"
android:layout_alignRight="#+id/application"
android:layout_alignEnd="#+id/application"
android:layout_marginBottom="135dp"
android:hint="Username"
android:textColorHint="#000000"
/>
<EditText
android:layout_width="200dp"
android:layout_height="wrap_content"
android:id="#+id/password"
android:layout_alignTop="#+id/username"
android:layout_alignRight="#+id/username"
android:layout_alignEnd="#+id/username"
android:layout_marginTop="52dp"
android:hint="Password"
android:textColorHint="#000000"
android:password="true" />
<Button
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="OK"
android:id="#+id/ok"
android:layout_below="#+id/password"
android:layout_alignLeft="#+id/application"
android:layout_alignStart="#+id/application"
android:onClick="okay" />
XML of Login Activity (2nd Activity)
<ImageView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/login_bckgrnd"
android:src="#drawable/login_bckgrnd"
android:scaleType="centerCrop"
/>
<ListView
android:id="#+id/list_view"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ListView>
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.admin.mobilegroceryapp" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<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=".Login"
android:label="#string/title_activity_login" >
</activity>
</application>
</manifest>
logcat
.085 2019-2087/? I/InputDispatcher﹕ Delivering touch to current input target: action: 0x0
09-29 01:54:28.085 2019-2087/? I/InputDispatcher﹕ Delivering touch to current input target: action: 0x0
09-29 01:54:28.085 2019-2087/? I/InputDispatcher﹕ Delivering touch to current input target: action: 0x0
09-29 01:54:28.085 2019-2087/? I/InputDispatcher﹕ Delivering touch to current input target: action: 0x0
09-29 01:54:28.085 2019-2087/? I/InputDispatcher﹕ Delivering touch to current input target: action: 0x0
09-29 01:54:28.190 2019-2088/? I/InputReader﹕ Touch event's action is 0x1 (deviceType=0) [pCnt=1, s=]
09-29 01:54:28.285 30351-30351/? I/dalvikvm﹕ Could not find method android.graphics.Bitmap.getAllocationByteCount, referenced from method com.facebook.imagepipeline.a.d.a.a
09-29 01:54:28.285 30351-30351/? W/dalvikvm﹕ VFY: unable to resolve virtual method 625: Landroid/graphics/Bitmap;.getAllocationByteCount ()I
09-29 01:54:28.285 30351-30351/? D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0006
09-29 01:54:28.355 30482-30482/? D/dalvikvm﹕ WAIT_FOR_CONCURRENT_GC blocked 0ms
09-29 01:54:28.355 2019-2074/? D/BatteryService﹕ update start
09-29 01:54:28.360 2019-2079/? D/KeyguardViewMediator﹕ setHidden false
09-29 01:54:28.360 1732-1732/? I/SurfaceFlinger﹕ id=13169 Removed TcreenSaver idx=4 MapSz=10
Hope some pro help me to my problem. Somebody says It's simple but I can't resolved sir.

You need to add Login Activity to your AndroidManifest.xml so that the android operating system can find the Activity that the intent is referencing.
<activity
android:name=".Activities.Login"
android:label="Login" />

You really need to show us your stacktrace for any useful feedback. I suspect you aren't declaring the Login activity in your AndroidManifest.xml correctly.
LogCat will contain the error stacktrace. Most likely you will see a giant block of red text that will indicate the part we are interested in. Below is an example of one of my stacktraces. Hopefully it helps you find it.
java.lang.RuntimeException: Unable to start activity ComponentInfo{package.name.ThingDetailActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'long com.package.api.model.Thing.getId()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Method.java)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

Android application crashed

I'm doing an app for Android. I have a main activity (not the default MainActivity.java, other activity named HotelPresentacion.java that has 3 buttons for insert/check registers or exit the app).
If I touch the Registrar button, supposedly I can register, but the app stops unexpectedly. If I touch the Registros button I can visualize the registers of my app, but when I touch one register (a short touch or long short) for only visualize or edit the app again stops unexpectedly.
I modified my androidmanifest.xml to set HotelPresentacion.java as my default starting activity.
This is the code of the HotelPresentacion.java
package com.example.lab007;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
public class HotelPresentacion extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_hotel_presentacion);
}
public void onReservar(View v){
Intent i=new Intent(HotelPresentacion.this, ReservacionFormulario.class);
startActivity(i);
}
public void onVer(View v){
Intent i=new Intent(HotelPresentacion.this, MainActivity.class);
startActivity(i);
}
public void onSalir(View v){
finish();
}
}
My androidmanifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.lab007"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".HotelPresentacion"
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="com.example.lab007.ReservacionFormulario"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.example.lab007.MainActivity"
android:label="#string/app_name" >
</activity>
</application>
</manifest>
LOGCAT
10-25 11:16:38.880: E/AndroidRuntime(4247): FATAL EXCEPTION: main
10-25 11:16:38.880: E/AndroidRuntime(4247): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.lab007/com.example.lab007.ReservacionFormulario}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.os.Handler.dispatchMessage(Handler.java:99)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.os.Looper.loop(Looper.java:130)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread.main(ActivityThread.java:3687)
10-25 11:16:38.880: E/AndroidRuntime(4247): at java.lang.reflect.Method.invokeNative(Native Method)
10-25 11:16:38.880: E/AndroidRuntime(4247): at java.lang.reflect.Method.invoke(Method.java:507)
10-25 11:16:38.880: E/AndroidRuntime(4247): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
10-25 11:16:38.880: E/AndroidRuntime(4247): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
10-25 11:16:38.880: E/AndroidRuntime(4247): at dalvik.system.NativeStart.main(Native Method)
10-25 11:16:38.880: E/AndroidRuntime(4247): Caused by: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ListActivity.onContentChanged(ListActivity.java:243)
10-25 11:16:38.880: E/AndroidRuntime(4247): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:212)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.Activity.setContentView(Activity.java:1657)
10-25 11:16:38.880: E/AndroidRuntime(4247): at com.example.lab007.ReservacionFormulario.onCreate(ReservacionFormulario.java:39)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-25 11:16:38.880: E/AndroidRuntime(4247): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
10-25 11:16:38.880: E/AndroidRuntime(4247): ... 11 more
The class ReservacionFormulario.java
package com.example.lab007;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.DialogInterface;
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.widget.CheckBox;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Spinner;
import android.widget.Toast;
public class ReservacionFormulario extends ListActivity{
private ComplejoDBAdapter dbAdapterComplejo;
private ComplejoSpinnerAdapter complejoSpinnerAdapter;
private int modo ;
private long id ;
private Reservacion reserva = new Reservacion(this);
private EditText nombre;
private EditText apellidos;
//private DatePicker fechaInicio;
//private DatePicker fechaFin;
private Spinner complejo ;
private Button boton_guardar;
private Button boton_cancelar;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_reservacion_formulario);
Intent intent = getIntent();
Bundle extra = intent.getExtras();
if (extra == null) return;
nombre = (EditText) findViewById(R.id.nombre);
apellidos = (EditText) findViewById(R.id.apellidos);
//fechaInicio = (DatePicker) findViewById(R.id.);
//fechaInicio = (DatePicker) findViewById(R.id.);
complejo = (Spinner) findViewById(R.id.complejo);
boton_guardar = (Button) findViewById(R.id.boton_guardar);
boton_cancelar = (Button) findViewById(R.id.boton_cancelar);
complejoSpinnerAdapter = new ComplejoSpinnerAdapter(this, Complejo.getAll(this, null));
complejo.setAdapter(complejoSpinnerAdapter);
if (extra.containsKey(ReservacionDBAdapter.C_COL_ID)){
id = extra.getLong(ReservacionDBAdapter.C_COL_ID);
consultar(id);
}
establecerModo(extra.getInt(ReservacionActivity.C_MODO));
boton_guardar.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v){
guardar();
}
});
boton_cancelar.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v){
cancelar();
}
});
}
private void establecerModo(int m)
{
this.modo = m ;
if (modo == ReservacionActivity.C_VISUALIZAR){
this.setTitle(nombre.getText().toString());
this.setEdicion(false);
}
else if (modo == ReservacionActivity.C_CREAR){
this.setTitle("Nuevo reservacion");
this.setEdicion(true);
}
else if (modo == ReservacionActivity.C_EDITAR){
this.setTitle("Editar reservacion");
this.setEdicion(true);
}
}
private void consultar(long id){
reserva = Reservacion.find(this, id);
nombre.setText(reserva.getNombre());
apellidos.setText(reserva.getApellidos());
complejo.setSelection(complejoSpinnerAdapter.getPositionById(reserva.getComplejoId()));
}
private void setEdicion(boolean opcion){
nombre.setEnabled(opcion);
apellidos.setEnabled(opcion);
complejo.setEnabled(opcion);
// Controlamos visibilidad de botonera
LinearLayout v = (LinearLayout) findViewById(R.id.botonera);
if (opcion)
v.setVisibility(View.VISIBLE);
else
v.setVisibility(View.GONE);
}
private void guardar(){
/*verificar si funciona*/
try{
if(nombre.length()<=0){
reserva.setNombre(nombre.getText().toString());
}
}catch(Exception e){
}
reserva.setApellidos(apellidos.getText().toString());
reserva.setComplejoId(complejo.getSelectedItemId());
reserva.save();
if (modo == ReservacionActivity.C_CREAR){
Toast.makeText(ReservacionFormulario.this, "Creado", Toast.LENGTH_SHORT).show();
}
else if (modo == ReservacionActivity.C_EDITAR){
Toast.makeText(ReservacionFormulario.this, "Modificado", Toast.LENGTH_SHORT).show();
}
setResult(RESULT_OK);
finish();
}
private void cancelar(){
setResult(RESULT_CANCELED, null);
finish();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
menu.clear();
if (modo == ReservacionActivity.C_VISUALIZAR)
getMenuInflater().inflate(R.menu.reservacion_formulario_ver, menu);
else
getMenuInflater().inflate(R.menu.reservacion_formulario_editar, menu);
return true;
}
#Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
switch (item.getItemId()){
case R.id.menu_eliminar:
borrar(id);
return true;
case R.id.menu_cancelar:
cancelar();
return true;
case R.id.menu_guardar:
guardar();
return true;
case R.id.menu_editar:
establecerModo(ReservacionActivity.C_EDITAR);
return true;
}
return super.onMenuItemSelected(featureId, item);
}
private void borrar(final long id){
AlertDialog.Builder dialogEliminar = new AlertDialog.Builder(this);
dialogEliminar.setIcon(android.R.drawable.ic_dialog_alert);
dialogEliminar.setTitle("Eliminar");
dialogEliminar.setMessage("¿Desea eliminar?");
dialogEliminar.setCancelable(false);
dialogEliminar.setPositiveButton(getResources().getString(android.R.string.ok), new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int boton) {
reserva.delete();
Toast.makeText(ReservacionFormulario.this, "Eliminado", Toast.LENGTH_SHORT).show();
setResult(RESULT_OK);
finish();
}
});
dialogEliminar.setNegativeButton(android.R.string.no, null);
dialogEliminar.show();
}
}
The activity_reservacion_formulario.xml
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/ScrollView1"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="10dp" >
<!-- Nombre -->
<TextView
android:id="#+id/label_nombre"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Nombre" />
<EditText
android:id="#+id/nombre"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/label_nombre"
android:maxLength="40"
android:ems="10" />
<!-- Apellidos -->
<TextView
android:id="#+id/label_apellidos"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/nombre"
android:maxLength="60"
android:text="Apellidos" />
<EditText
android:id="#+id/apellidos"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/label_apellidos"
android:ems="10" />
<!-- Fecha de Inicio -->
<!-- <TextView
android:id="#+id/label_fechainicio"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/apellidos"
android:text="Fecha de Inicio" />
<DatePicker
android:id="#+id/datePickerInicio"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/label_fechainicio" /> -->
<!-- Fecha de Fin -->
<!-- <TextView
android:id="#+id/label_fechafin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/datePickerInicio"
android:text="Fecha de Fin" />
<DatePicker
android:id="#+id/datePickerFin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/label_fechafin" /> -->
<!-- Spinner -->
<TextView
android:id="#+id/label_complejo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/datePickerFin"
android:text="Complejo" />
<Spinner
android:id="#+id/complejo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/label_complejo" />
<TextView
android:id="#+id/label_ciudad"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Complejo"
android:layout_below="#+id/complejo" />
<LinearLayout
android:id="#+id/botonera"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:gravity="center"
android:layout_below="#+id/datePickerFin"
android:orientation="horizontal" >
<Button
android:id="#+id/boton_cancelar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Cancelar" />
<Button
android:id="#+id/boton_guardar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Guardar" />
</LinearLayout>
</RelativeLayout>
</ScrollView>
This is the entire project:
Project
I'll appreciante any help for solve my problem. Thanks

Replace
public class ReservacionFormulario extends ListActivity{
with
public class ReservacionFormulario extends Activity{
As you have extended the ListActivity so Android is searching for the a ListView with Id list, but In your XML there is no any such type of ListView.

From the crash log i guess its.
Change ListActivity to Activity

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".

Unfortunately app has stopped (At first activity)

I've read a lot of threads about this "common" problem developing Android apps.
I've also noticed that it all depends on various problem, some from the manifest, some from Java classes.
I'll paste my code here, please if someone see something weird, please tell me.
As you can see, I'm using the MVC-pattern. Please tell me if you need the Model & Controller java class too.
-----ENTER VIEW JAVA CLASS-----
package kalle.jack.gui_tictactoe_android;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.Button;
import android.widget.TextView;
public class EnterView extends Activity {
private Model _model;
private Controller _controller;
public EnterView (Model aModel, Controller aController) {
_model = aModel;
_controller = aController;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_enter_view);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.enter_view, menu);
return true;
}
public void startClicked () {
TextView s = (TextView) findViewById(R.id.text1);
String player1 = (String) s.getText();
TextView t = (TextView) findViewById(R.id.text2);
String player2 = (String) t.getText();
Button b = (Button) findViewById(R.id.button1);
b.setId(10);
int a = b.getId();
_controller.setNames(player1, player2);
_controller.buttonClicked(a);
}
}
------XML MANIFEST-------
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="kalle.jack.gui_tictactoe_android"
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"
android:debuggable="true">
<activity
android:name="kalle.jack.gui_tictactoe_android.EnterView"
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="kalle.jack.gui_tictactoe_android.PlayView"
android:label="#string/title_activity_play_view" >
</activity>
</application>
</manifest>
----------XML activity_enter_view-----------
<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=".EnterView" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="49dp"
android:text="Enter your names below..."
android:textAppearance="?android:attr/textAppearanceLarge" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="85dp"
android:text="Start Game"
android:onClick="startClicked"/>
<EditText
android:id="#+id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="42dp"
android:ems="10"
android:inputType="textPersonName"
android:text="Player 1" />
<EditText
android:id="#+id/text2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:ems="10"
android:inputType="textPersonName"
android:text="Player 2" >
<requestFocus />
</EditText>
</RelativeLayout>
-----FROM LOGCAT --------
05-26 06:33:24.460: E/AndroidRuntime(943): FATAL EXCEPTION: main
05-26 06:33:24.460: E/AndroidRuntime(943): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{kalle.jack.gui_tictactoe_android/kalle.jack.gui_tictactoe_android.EnterView}: java.lang.InstantiationException: can't instantiate class kalle.jack.gui_tictactoe_android.EnterView; no empty constructor
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2106)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread.access$600(ActivityThread.java:141)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.os.Handler.dispatchMessage(Handler.java:99)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.os.Looper.loop(Looper.java:137)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread.main(ActivityThread.java:5041)
05-26 06:33:24.460: E/AndroidRuntime(943): at java.lang.reflect.Method.invokeNative(Native Method)
05-26 06:33:24.460: E/AndroidRuntime(943): at java.lang.reflect.Method.invoke(Method.java:511)
05-26 06:33:24.460: E/AndroidRuntime(943): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-26 06:33:24.460: E/AndroidRuntime(943): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-26 06:33:24.460: E/AndroidRuntime(943): at dalvik.system.NativeStart.main(Native Method)
05-26 06:33:24.460: E/AndroidRuntime(943): Caused by: java.lang.InstantiationException: can't instantiate class kalle.jack.gui_tictactoe_android.EnterView; no empty constructor
05-26 06:33:24.460: E/AndroidRuntime(943): at java.lang.Class.newInstanceImpl(Native Method)
05-26 06:33:24.460: E/AndroidRuntime(943): at java.lang.Class.newInstance(Class.java:1319)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.Instrumentation.newActivity(Instrumentation.java:1054)
05-26 06:33:24.460: E/AndroidRuntime(943): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2097)
05-26 06:33:24.460: E/AndroidRuntime(943): ... 11 more

Firstly, activities must have empty constructors. The system cannot call or instantiate your activity if it requires parameters. Remove the parameters or do not define a constructor at all.
Remove:
public EnterView (Model aModel, Controller aController) {
_model = aModel;
_controller = aController;
}
The next error you would encounter would be the startClicked() method, as praveenLal said. It should accept a View parameter which will represent the clicked button when the method is called.

Please use public void startClicked (View v){
........
....
}
instead of public void startClicked ().

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.