Android compiles but crashes

Tag: java,android,android-layout,listview,android-intent

i am trying to develop my first app. It compiles and installs but crashes when I open it.

Here is the Code

public class MainActivity extends ActionBarActivity implements OnItemClickListener {
private  ListView listview;
private DrawerLayout drawerlayout;
private ActionBarDrawerToggle drawerListener;
private LinearLayout menu;
private myAdapter myadapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    listview=(ListView)findViewById(R.id.ListView);




    myadapter=new myAdapter(this);
    listview.setOnItemClickListener(this);
    listview.setAdapter(myadapter);
    drawerlayout=(DrawerLayout)findViewById(R.id.drawerLayout);

    drawerListener= new ActionBarDrawerToggle(this,drawerlayout,R.drawable.ic_ic_drawer,R.string.app_name, R.string.app_name){
            @Override
            public void onDrawerClosed(View drawerView) {

                Toast.makeText(MainActivity.this, "ola", Toast.LENGTH_LONG).show();
                menu=(LinearLayout)findViewById(R.id.menu_lateral);
                 menu.setVisibility(View.VISIBLE);
                super.onDrawerClosed(drawerView);

        }



            @Override
            public void onDrawerOpened(View drawerView) {
                menu=(LinearLayout)findViewById(R.id.menu_lateral);
                 menu.setVisibility(View.GONE);
                super.onDrawerOpened(drawerView);
            }
    };




    drawerlayout.setDrawerListener(drawerListener);
    getSupportActionBar().setHomeButtonEnabled(true);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

}


@Override
public void onPostCreate(Bundle savedInstanceState,
        PersistableBundle persistentState) {
    drawerListener.syncState();
    super.onPostCreate(savedInstanceState, persistentState);
}

@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) {
if(drawerListener.onOptionsItemSelected(item)){
    return true;
}
    return super.onOptionsItemSelected(item);
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    // TODO Auto-generated method stub
    super.onConfigurationChanged(newConfig);
    drawerListener.onConfigurationChanged(newConfig);
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
        long id) {

    class myAdapter extends BaseAdapter{
private Context context;
View row=null;
String [] menu;
int [] images ={R.drawable.ic_contact, R.drawable.menu, R.drawable.ic_reservas, R.drawable.ic_map, R.drawable.galeria, R.drawable.info, R.drawable.facebook };

public myAdapter(Context context) {
menu=context.getResources().getStringArray(R.array.slide);
this.context=context;
}
@Override
public int getCount() {
    // TODO Auto-generated method stub
    return menu.length;
}
@Override
public Object getItem(int position) {
    // TODO Auto-generated method stub
    return menu[position];
}
@Override
public long getItemId(int position) {
    // TODO Auto-generated method stub
    return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    if(convertView==null){
        View row=null;
        LayoutInflater inflater=(LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        row=inflater.inflate(R.layout.custom_row, parent, false);
    }
    else
    {
        row=convertView;
    }

    TextView titulo=(TextView) row.findViewById(R.id.textView1);
    ImageView icone=(ImageView) row.findViewById(R.id.imageView1);

    titulo.setText(menu[position]);
    icone.setImageResource(images[position]);
    return row;
}

And here is the log cat

    06-13 18:55:12.842: D/OpenGLRenderer(4763): Render dirty regions requested: true
06-13 18:55:12.862: D/Atlas(4763): Validating map...
06-13 18:55:12.942: I/Adreno-EGL(4763): <qeglDrvAPI_eglInitialize:410>: EGL 1.4 QUALCOMM build: AU_LINUX_ANDROID_LA.AF.1.1.04.04.03.164.081_msm8960_LA.AF.1.1__release_AU ()
06-13 18:55:12.942: I/Adreno-EGL(4763): OpenGL ES Shader Compiler Version: E031.25.01.03
06-13 18:55:12.942: I/Adreno-EGL(4763): Build Date: 11/02/14 Sun
06-13 18:55:12.942: I/Adreno-EGL(4763): Local Branch: mybranch5454281
06-13 18:55:12.942: I/Adreno-EGL(4763): Remote Branch: quic/l_LNX.LA.3.6
06-13 18:55:12.942: I/Adreno-EGL(4763): Local Patches: NONE
06-13 18:55:12.942: I/Adreno-EGL(4763): Reconstruct Branch: AU_LINUX_ANDROID_LA.AF.1.1.04.04.03.164.081 + db92d1e + cb8de02 +  NOTHING
06-13 18:55:12.942: I/OpenGLRenderer(4763): Initialized EGL, version 1.4
06-13 18:55:12.972: D/OpenGLRenderer(4763): Enabling debug mode 0
06-13 18:55:13.072: D/AndroidRuntime(4763): Shutting down VM
06-13 18:55:13.102: E/AndroidRuntime(4763): FATAL EXCEPTION: main
06-13 18:55:13.102: E/AndroidRuntime(4763): Process: com.example.alambique, PID: 4763
06-13 18:55:13.102: E/AndroidRuntime(4763): java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference
06-13 18:55:13.102: E/AndroidRuntime(4763):     at com.example.alambique.myAdapter.getView(MainActivity.java:155)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.AbsListView.obtainView(AbsListView.java:2346)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.ListView.makeAndAddView(ListView.java:1864)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.ListView.fillDown(ListView.java:698)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.ListView.fillFromTop(ListView.java:759)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.ListView.layoutChildren(ListView.java:1673)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.AbsListView.onLayout(AbsListView.java:2150)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.support.v4.widget.DrawerLayout.onLayout(DrawerLayout.java:931)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.onLayout(FrameLayout.java:508)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.onLayout(FrameLayout.java:508)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.support.v7.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:493)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.onLayout(FrameLayout.java:508)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.LinearLayout.onLayout(LinearLayout.java:1466)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.widget.FrameLayout.onLayout(FrameLayout.java:508)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.View.layout(View.java:15596)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewGroup.layout(ViewGroup.java:4966)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2072)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1829)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5786)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.Choreographer.doCallbacks(Choreographer.java:580)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.Choreographer.doFrame(Choreographer.java:550)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.os.Handler.handleCallback(Handler.java:739)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.os.Handler.dispatchMessage(Handler.java:95)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.os.Looper.loop(Looper.java:135)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at android.app.ActivityThread.main(ActivityThread.java:5256)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at java.lang.reflect.Method.invoke(Native Method)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at java.lang.reflect.Method.invoke(Method.java:372)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898)
06-13 18:55:13.102: E/AndroidRuntime(4763):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
06-13 18:55:13.162: I/Process(4763): Sending signal. PID: 4763 SIG: 9

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Unfortunately, (My app) has stopped. Eclipse Android [duplicate]

java,android,eclipse,adt

In your MainActivity.java at line no 34 you are trying to initialize some widget that is not present in your xml layout which you have set it in your setContentView(R.layout.... That;s why you are geting nullpointerexception. EDIT: change your setContentView(R.layout.activity_main) to setContentView(R.layout.fragment_main)...

Android String if-statement

java,android,string

Correct me if I'm wrong. If you're saying that your code looks like this: new Thread(new Runnable() { public void run() { // thread code if (ready.equals("yes")) { // handler code } // more thread code }).start(); // later on... ready = "yes"; And you're asking why ready = "yes"...

how does android ImageView resize my image?

android

I'm not sure what are you trying to do, are you trying to have the imageview to adapt to your image's size or are you trying to have your image view at a fixed size? When the image is shown on a xhdpi screen will the image be scaled to...