I have an Activity
that loads 2 tabs in the ActionBar
. Tab 1 loads a Fragment
that will will inflate a WebView
, while Tab 2 loads a Fragment
with a map. Initially, I have the problem of changing tabs that causes the app to crash. I have followed the instructions here and implemented onDestroyView()
.
The problem now is that if I press the back button from Tab 1 (WebView
), it exits the Activity
properly. But if I do it on Tab 2 (map), the app crashes. The exact same scenario applies to when I change the orientation. I am convinced that it has something to do with the onDestroyView()
, but I am not sure what it is.
I have even attempted to Override
the back button, but nothing works.
Here is my code to provide some context:
The Activity Class:
public class MyActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Displaying the tabs by calling ActionBar
ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
//Details Tab
String label1 = getResources().getString(R.string.details);
Tab tab = actionBar.newTab();
tab.setText(label1);
TabListenert1 = new TabListener (this, label1, DetailsFragment.class);
tab.setTabListener(t1);
actionBar.addTab(tab);
//Map Tab
String label2 = getResources().getString(R.string.map);
tab = actionBar.newTab();
tab.setText(label2);
TabListenert2 = new TabListener (this, label2, MapFragment.class);
tab.setTabListener(t2);
actionBar.addTab(tab);
}
private class TabListenerimplements ActionBar.TabListener {
private Fragment mFragment;
private final Activity mActivity;
private final String mTag;
private final ClassmClass;
/**
* Constructor used each time a new tab is created.
*
* @param activity
* The host Activity, used to instantiate the fragment
* @param tag
* The identifier tag for the fragment
* @param clz
* The fragment's Class, used to instantiate the fragment
*/
public TabListener(Activity activity, String tag, Classclz) {
mActivity = activity;
mTag = tag;
mClass = clz;
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
// Check if the fragment is already initialized
if (mFragment == null) {
// If not, instantiate and add it to the activity
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.add(android.R.id.content, mFragment, mTag);
} else {
// If it exists, simply attach it in order to show it
ft.attach(mFragment);
}
}
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
if (mFragment != null) {
// Detach the fragment, because another one is being attached
ft.detach(mFragment);
}
}
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// User selected the already selected tab. Usually do nothing.
}
}
@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;
} }
DetailsFragment:
public class DetailsFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.morning, container, false);
WebView webview = (WebView) v.findViewById(R.id.details);
webview.loadUrl("file:///android_asset/pools/details.html");
return v;
} }
MapFragment:
public class MapFragment extends Fragment {
static final LatLng mapLatLng = new LatLng("some numbers", "some numbers");
private GoogleMap map;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.map, container, false);
map = ((MapFragment)getFragmentManager().findFragmentById(R.id.map)).getMap();
Marker amksc = map.addMarker(new MarkerOptions().position(mapLatLng).title("Map"));
map.moveCamera(CameraUpdateFactory.newLatLngZoom(mapLatLng, 18));
return v;
}
@Override
public void onDestroyView() {
super.onDestroyView();
MapFragment destroyMe = (MapFragment)getFragmentManager().findFragmentById(R.id.map);
if (destroyMe != null) {
getFragmentManager().beginTransaction().remove(destroyMe).commit();
}
} }
Thanks for reading such a long post. Any help is greatly appreciated. I will be away for awhile without my laptop (15 days to be exact), so I may not be able to respond and test out your answer, but rest assured that I will =)
Thanks in advance!
.
stackoverflow.comm
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