android-fragmentactivity

Context: I have an Activity with a Fragment and 3 InnerFragments . When the Fragment onDestroy() is called, I want to remove the inner fragments from the FragmentManager . The code from onDestroy() is below. Problem: FragmentManager throws NullPointerException , probably when commitAllowingStateLoss() is called. I don't understand why. @Override public void onDestroy() { super.onDestroy(); if (getFragmentManager().findFragmentById(R.id.fragment_framelayout_left) != null) { FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction(); fragmentTransaction.remove

I want to set toolbar on my activity which extends FragmentActivity . I know that for use setSuppoertActionBar(toolbar) method we extends AppCompatActivity instead of FragmentActivity but I override the onMenuItemSelected(int featureId, MenuItem item) method which is final in AppCompatActivity and final method cannot override. so I'm restricted to extends FragmentActivity . Here is my code: public class MainActivity extends FragmentActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Toolbar

I want to open Android4.2 setting WifiDisplaySettingsActivity from my app. I tried Intent i; PackageManager manager = getActivity().getPackageManager(); try { i = manager.getLaunchIntentForPackage("com.android.settings.wfd"); if (i == null) throw new PackageManager.NameNotFoundException(); i.addCategory(Intent.ACTION_MAIN); startActivity(i); } catch (PackageManager.NameNotFoundException e) { } and final Intent intent = new Intent(Intent.ACTION_MAIN, null); intent.addCategory(Intent.CATEGORY_LAUNCHER); final ComponentName cn = new ComponentName("com.android.settings.wfd","com.android.settings

Backgroud: i have a menu on the left, and different scrollable contents on the right. i wanted to save the scrolled position. But i failed. Then ... I have set up a very simple project to test it. In words, i have a menu on the left, and different contents all holding an <EditText> on the right. (of the same class though, they are of different instances) In codes, (very simple) content.xml <EditText xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/text" android:layout_width="match_parent" android:layout_height="wrap_content" android:hint="Please save my text ..." />

Here is my code: activity_main.xml <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=".MainActivity" > <android.support.v4.view.ViewPager android:id="@+id/pager" android:layout_width="fill_parent" android:layout_height=

I can successfully intercept the ActionBar home button from my NavigationDrawerFragment , which is added to my MainActivity , like so: @Override public boolean onOptionsItemSelected(MenuItem item) { if (!loggedIn() && item.getItemId() == android.R.id.home) { login(); return true; } return super.onOptionsItemSelected(item); } However, in my ComposeActivity with ComposeFragment this does not work. onOptionsItemSelected is not called on the fragment. I have debugged the code and the issue seems to come down to the design of the Android support library. It appears that both FragmentActivity and

I was just wondering, can fragment creation only have one instance or singleton? I went through Google iosched project too. They simply create Fragment a = new Fragment(); Whenever they want... Suppose eg: public static FragmentManager instance; public static FragmentManager getInstance() { if (instance == null) { instance = new FragmentManager(); } return instance; } public TestFragment getTestFragment() { if (testFragment == null) { testFragment = new TestFragment (); } return testFragment } } Can I use everywhere FragmentManager.getInstance().getTestFragment() for transaction? eg: