I have problem with adding new item through ActionBar item click. I got all the error below and the code is just beneath. If anyone would be so kind to tell me what stupid mistake I made I would be grateful.
LogCat:
08-26 19:17:57.767: E/AndroidRuntime(29108): FATAL EXCEPTION: main
08-26 19:17:57.767: E/AndroidRuntime(29108): Process: com.klangstudios.dailyachiever, PID: 29108
08-26 19:17:57.767: E/AndroidRuntime(29108): java.lang.NullPointerException
08-26 19:17:57.767: E/AndroidRuntime(29108): at com.klangstudios.dailyachiever.Lista$StableArrayAdapter.getItemId(Lista.java:81)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.AbsListView.obtainView(AbsListView.java:2291)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.ListView.measureHeightOfChildren(ListView.java:1263)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.ListView.onMeasure(ListView.java:1175)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.View.measure(View.java:16540)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5137)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.View.measure(View.java:16540)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5137)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.View.measure(View.java:16540)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5137)
08-26 19:17:57.767: E/AndroidRuntime(29108): at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.View.measure(View.java:16540)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5137)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
08-26 19:17:57.767: E/AndroidRuntime(29108): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.View.measure(View.java:16540)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1942)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1132)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1321)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1019)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5725)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.Choreographer.doCallbacks(Choreographer.java:574)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.Choreographer.doFrame(Choreographer.java:544)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.os.Handler.handleCallback(Handler.java:733)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.os.Handler.dispatchMessage(Handler.java:95)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.os.Looper.loop(Looper.java:136)
08-26 19:17:57.767: E/AndroidRuntime(29108): at android.app.ActivityThread.main(ActivityThread.java:5086)
08-26 19:17:57.767: E/AndroidRuntime(29108): at java.lang.reflect.Method.invokeNative(Native Method)
08-26 19:17:57.767: E/AndroidRuntime(29108): at java.lang.reflect.Method.invoke(Method.java:515)
08-26 19:17:57.767: E/AndroidRuntime(29108): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
08-26 19:17:57.767: E/AndroidRuntime(29108): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
08-26 19:17:57.767: E/AndroidRuntime(29108): at dalvik.system.NativeStart.main(Native Method)
Just don't know why it won't work:
public class Lista extends Activity{
ArrayList<String> list;
ListView listview;
StableArrayAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.lista);
listview = (ListView) findViewById(R.id.listView1);
String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
"Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
"Linux", "OS/2", "Ubuntu", "Windows7", "Max OS X", "Linux",
"OS/2", "Ubuntu", "Windows7", "Max OS X", "Linux", "OS/2",
"Android", "iPhone", "WindowsMobile" };
list = new ArrayList<String>();
adapter = new StableArrayAdapter(this, android.R.layout.simple_list_item_1, list);
listview.setAdapter(adapter);
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, final View view,
int position, long id) {
final String item = (String) parent.getItemAtPosition(position);
view.animate().setDuration(2000).alpha(0)
.withEndAction(new Runnable() {
@Override
public void run() {
list.remove(item);
adapter.notifyDataSetChanged();
view.setAlpha(1);
}
});
}
});
}
private class StableArrayAdapter extends ArrayAdapter<String> {
HashMap<String, Integer> mIdMap = new HashMap<String, Integer>();
public StableArrayAdapter(Context context, int textViewResourceId,
List<String> objects) {
super(context, textViewResourceId, objects);
for (int i = 0; i < objects.size(); ++i) {
mIdMap.put(objects.get(i), i);
}
}
@Override
public long getItemId(int position) {
String item = getItem(position);
return mIdMap.get(item);
}
@Override
public boolean hasStableIds() {
return true;
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu items for use in the action bar
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu, menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle presses on the action bar items
switch (item.getItemId()) {
case R.id.action_add:
doThis();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void doThis(){
list.add("Abba");
adapter.notifyDataSetChanged();
}
}
return mIdMap.get(item);
change these line to
return position;