ClassCastException fragments.MainActivity must implement OnHeadlineSelectedListener
Problem:
You have two class with similar names HeadLinesFragment and HeadMyLinesFragment with OnHeadlineSelectedListener.
Check if call correct class in MainActivity.
For example if use HeadMyLinesFragment change implement to HeadMyLinesFragment too!
You have two class with similar names HeadLinesFragment and HeadMyLinesFragment with OnHeadlineSelectedListener.
Check if call correct class in MainActivity.
For example if use HeadMyLinesFragment change implement to HeadMyLinesFragment too!
public class MainActivity extends FragmentActivity
implements HeadLinesFragment.OnHeadlineSelectedListener {
// wrong implements you need correct class name
//implements HeadMyLinesFragment.OnHeadlineSelectedListener
//............
HeadMyLinesFragment firstFragment = new HeadMyLinesFragment(); // because in code using HeadMyLinesFragment
396LW NO topic_id
AD
Další témata ....(Topics)
Environment.getExternalStorageDirectory()+ File.separator
AndroidManifest.xml
Boolean canWrite = Environment.getExternalStorageDirectory().canWrite() ;
if(canWrite){
File f = new File(Environment.getExternalStorageDirectory()
+ File.separator + "my_image.jpg")
f.createNewFile();
}else{
}
AndroidManifest.xml
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
Call requires permission which may be rejected by user: code should explicitly check to see if permission is available (with `checkPermission`) or explicitly handle a potential `SecurityException`
try {
// your code for example:
// LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Criteria criteria = new Criteria();
// provider = locationManager.getBestProvider(criteria, false);
// locationManager.requestLocationUpdates(provider, 400, 1, this);
} catch (SecurityException e) {
e.printStackTrace();
}
Definition of ListView in layout main.xml file Android example
Code in Main.java ListView example source code Java Android
<ListView android:id="@+id/idListView"
android:background="#7700CC00"
android:layout_height="wrap_content"
android:layout_width="fill_parent" />
Code in Main.java ListView example source code Java Android
public class Main extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ListView mlistView = (ListView) findViewById(R.id.idListView);
mlistView.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1,
new String[] {"Game", "Help", "Home site"}));
mlistView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text Game, Help, Home
Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
Toast.LENGTH_SHORT).show();
}
});
}
}
FrameLayou, fragment have to unique id android:id="@+id/your_id_unique"
<FrameLayout xmlns:android="//schemas.android.com/apk/res/android"
xmlns:tools="//schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<fragment
android:id="@+id/your_id_unique"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="cz.okhelp.notepad.AddNoteFragment"
tools:layout="@layout/add_note" />
</FrameLayout>
Context context = getApplicationContext();
Drawable drawable = context.getResources().getDrawable(R.drawable.my_image);
// convert drawable to bitmap
Bitmap bitmap = ((BitmapDrawable)drawable).getBitmap();
// convert bitmap to drawable
Drawable d = new BitmapDrawable(bitmap);
Android example source code.
Editace: 2016-04-01 12:06:43
Počet článků v kategorii: 396
Url:classcastexception-fragments-mainactivity-must-implement-onheadlineselectedlistener