android.support.v4.app.FragmentManager#findFragmentById ( )源码实例Demo

private void attachDeviceWithWebViewFragment() {
    FragmentManager supportFragmentManager = getSupportFragmentManager();
    FreightTrackMapWithWebViewFragment fragment = (FreightTrackMapWithWebViewFragment) supportFragmentManager.findFragmentById(R.id.content_main);
    if (fragment == null) {
        fragment = FreightTrackMapWithWebViewFragment.newInstance(mFreight.getId(), mFreight.getName());
        ActivityUtils.replaceFragmentToActivity(supportFragmentManager, fragment, R.id.content_main);
    }

    boolean mUsingWebView = "zh-CN".equals(LanguageUtil.getLanguage()) ? false : true;

    new FreightTrackMapWithWebViewPresenter(
            mUsingWebView,
            mFreight.getId(),
            mFreight.getName(),
            getApplicationContext(),
            fragment,
            SchedulerProvider.getInstance());
}
 

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(getLayoutId());

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.id_fragmentContainer);

    if (fragment == null)
    {
        fragment = createFragment();
        fm.beginTransaction().add(R.id.id_fragmentContainer, fragment)
                .commit();
    }

}
 

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_recycler);

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.fragment_container);

    if (fragment == null) {
        fragment = new RecyFragment();
        fm.beginTransaction()
                .add(R.id.fragment_container, fragment)
                .commit();
    }

}
 

public void updateLib() {
    if (mPreventRescan){
        mPreventRescan = false;
        return;
    }
    FragmentManager fm = getSupportFragmentManager();
    Fragment current = fm.findFragmentById(R.id.fragment_placeholder);
    if (current != null && current instanceof IRefreshable)
        ((IRefreshable) current).refresh();
    else
        MediaLibrary.getInstance().scanMediaItems();
    Fragment fragment = fm.findFragmentByTag(SidebarAdapter.SidebarEntry.ID_AUDIO);
    if (fragment != null && !fragment.equals(current)) {
        ((MediaBrowserFragment)fragment).clear();
    }
    fragment = fm.findFragmentByTag(SidebarAdapter.SidebarEntry.ID_VIDEO);
    if (fragment != null && !fragment.equals(current)) {
        ((MediaBrowserFragment)fragment).clear();
    }
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.fragment_container);
    if (fragment == null) {
        fragment = new ImagesFragment();
        fm.beginTransaction().add(R.id.fragment_container, fragment)
                .commit();
    }

    initImageLoader();

}
 

@Override
public void onBackStackChanged() {
    FragmentManager fm = getSupportFragmentManager();
    Fragment current = fm.findFragmentById(R.id.content_view);
    if (current == null) {
        // no more fragments in the stack. finish.
        finish();
        return;
    }
    Page page = Page.forName(current);
    binding.navView.setCheckedItem(page.getMenuId());
    binding.toolbar.setTitle(page.getTitleResId());
    toggleToolbarElevation(page.shouldToggleToolbar());
    if (current instanceof StackedPageListener) {
        StackedPageListener l = (StackedPageListener) current;
        l.onTop();
    }
}
 

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(getLayoutId());

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.id_fragmentContainer);

    if (fragment == null)
    {
        fragment = createFragment();
        fm.beginTransaction().add(R.id.id_fragmentContainer, fragment)
                .commit();
    }

}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    FragmentManager fm = getSupportFragmentManager();
    BatchStepSensorFragment fragment =
            (BatchStepSensorFragment) fm.findFragmentByTag(FRAGTAG);

    if (fragment == null) {
        FragmentTransaction transaction = fm.beginTransaction();
        fragment = new BatchStepSensorFragment();
        transaction.add(fragment, FRAGTAG);
        transaction.commit();
    }

    // Use fragment as click listener for cards, but must implement correct interface
    if (!(fragment instanceof OnCardClickListener)){
        throw new ClassCastException("BatchStepSensorFragment must " +
                "implement OnCardClickListener interface.");
    }
    OnCardClickListener clickListener = (OnCardClickListener) fm.findFragmentByTag(FRAGTAG);

    mRetentionFragment = (StreamRetentionFragment) fm.findFragmentByTag(RETENTION_TAG);
    if (mRetentionFragment == null) {
        mRetentionFragment = new StreamRetentionFragment();
        fm.beginTransaction().add(mRetentionFragment, RETENTION_TAG).commit();
    } else {
        // If the retention fragment already existed, we need to pull some state.
        // pull state out
        CardStreamState state = mRetentionFragment.getCardStream();

        // dump it in CardStreamFragment.
        mCardStreamFragment =
                (CardStreamFragment) fm.findFragmentById(R.id.fragment_cardstream);
        mCardStreamFragment.restoreState(state, clickListener);
    }
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_fragment);

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.fragment_container);

    if (fragment == null) {
        fragment = createFragment();
        fm.beginTransaction()
                .add(R.id.fragment_container, fragment)
                .commit();
    }
}
 

@Override
protected void onCreate(Bundle savedInstance){
    super.onCreate(savedInstance);
    setContentView(getLayoutResId());

    FragmentManager fragmentManager = getSupportFragmentManager();
    Fragment fragment = fragmentManager.findFragmentById(getContainerId());

    if (fragment == null){
        fragment = createFragment();
        fragmentManager.beginTransaction().add(getContainerId(), fragment).commit();
    }
}
 

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(getLayoutResId());
    FragmentManager manager = getSupportFragmentManager();
    Fragment fragment = manager.findFragmentById(R.id.fragment_container);

    if (fragment == null) {
        fragment = createFragment();
        manager.beginTransaction()
            .add(R.id.fragment_container, fragment)
            .commit();
    }
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
    super.onCreate(savedInstanceState);

    FragmentManager fm = getSupportFragmentManager();

    if (fm.findFragmentById(android.R.id.content) == null) {
        TwitterListFragment list = new TwitterListFragment();
        fm.beginTransaction().add(android.R.id.content, list).commit();
    }
}
 

private void initView()
{
    mDrawerLayout = (DrawerLayout) findViewById(R.id.id_drawerLayout);

    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.id_left_menu_container);
    if (fragment == null)
    {
        fm.beginTransaction().add(R.id.id_left_menu_container, new MenuLeftFragment()).commit();
    }
}
 

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_left_drawer_layout);

    mLeftDrawerLayout = (LeftDrawerLayout) findViewById(R.id.id_drawerlayout);
    mContentTv = (TextView) findViewById(R.id.id_content_tv);

    FragmentManager fm = getSupportFragmentManager();
    mMenuFragment = (LeftMenuFragment) fm.findFragmentById(R.id.id_container_menu);
    if (mMenuFragment == null)
    {
        fm.beginTransaction().add(R.id.id_container_menu, mMenuFragment = new LeftMenuFragment()).commit();
    }

    mMenuFragment.setOnMenuItemSelectedListener(new LeftMenuFragment.OnMenuItemSelectedListener()
    {
        @Override
        public void menuItemSelected(String title)
        {
            mLeftDrawerLayout.closeDrawer();
            mContentTv.setText(title);
        }
    });

}
 

public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	final String showId = getIntent().getStringExtra("showId");
	final int season = getIntent().getIntExtra("season", -1);
	final int episode = getIntent().getIntExtra("episode", -1);
	final FragmentManager fm = getSupportFragmentManager();
	
	if (fm.findFragmentById(android.R.id.content) == null) {
		fm.beginTransaction().add(android.R.id.content, EditTvShowEpisodeFragment.newInstance(showId, season, episode)).commit();
	}
}
 

public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	final String showId = getIntent().getStringExtra("showId");
       mToolbarColor = getIntent().getExtras().getInt(IntentKeys.TOOLBAR_COLOR);

	final FragmentManager fm = getSupportFragmentManager();
	
	if (fm.findFragmentById(android.R.id.content) == null) {
		fm.beginTransaction().add(android.R.id.content, EditTvShowFragment.newInstance(showId)).commit();
	}
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    FragmentManager fm = getSupportFragmentManager();

    // Create the list fragment and add it as our sole content.
    if (fm.findFragmentById(android.R.id.content) == null) {
        CursorLoaderListFragment list = new CursorLoaderListFragment();
        fm.beginTransaction().add(android.R.id.content, list).commit();
    }
}
 

private void attachDeviceGoogleMapFragment() {
    FragmentManager supportFragmentManager = getSupportFragmentManager();
    FreightTrackGoogleMapFragment fragment = (FreightTrackGoogleMapFragment) supportFragmentManager.findFragmentById(R.id.content_main);
    if (fragment == null) {
        fragment = FreightTrackGoogleMapFragment.newInstance(mFreight.getId(), mFreight.getName());
        ActivityUtils.replaceFragmentToActivity(supportFragmentManager, fragment, R.id.content_main);
    }
}
 

private void showFragment(Fragment fragment) {
    FragmentManager fragmentManager = getSupportFragmentManager();

    Fragment currentFragment = fragmentManager.findFragmentById(R.id.fragment_container);
    if (currentFragment != null) {
        return;
    }

    FragmentTransaction transaction = fragmentManager.beginTransaction();
    transaction.replace(R.id.fragment_container, fragment);
    transaction.commit();
}
 

private void addOrUpdateChildFragments() {
    showLoadingInProgress(false);

    final Bundle arguments = new Bundle();
    //TODO? arguments.putString(ARG_USER_ID,
    //        getUserId()); //Obtained in the super class.
    arguments.putString(ItemFragment.ARG_ITEM_ID,
            getItemId());

    //Add, or update, the nested child fragments.
    //This can only be done programmatically, not in the layout XML.
    //See http://developer.android.com/about/versions/android-4.2.html#NestedFragments

    final FragmentManager fragmentManager = getChildFragmentManager();
    SubjectFragment fragmentSubject = (SubjectFragment) fragmentManager.findFragmentById(R.id.child_fragment_subject);
    if (fragmentSubject == null) {
        fragmentSubject = new SubjectFragment();
        fragmentSubject.setArguments(arguments);
        fragmentManager.beginTransaction().replace(R.id.child_fragment_subject, fragmentSubject).commit();
    } else {
        //TODO: Is there some more standard method to do this,
        //to trigger the Fragments' onCreate()?
        fragmentSubject.setItemId(getItemId());
        //We don't wipe the inverted state (setInverted()) because this can happen after rotation,
        //not just when starting a new classification.
        fragmentSubject.update();
    }


    QuestionFragment fragmentQuestion = (QuestionFragment) fragmentManager.findFragmentById(R.id.child_fragment_question);
    if (fragmentQuestion == null) {
        fragmentQuestion = new QuestionFragment();
        fragmentQuestion.setArguments(arguments);
        fragmentManager.beginTransaction().replace(R.id.child_fragment_question, fragmentQuestion).commit();
    } else {
        //TODO: Is there some more standard method to do this,
        //to trigger the Fragments' onCreate()?
        fragmentQuestion.setGroupId(null); //Avoid any chance of us using the wrong groups's decision tree.
        fragmentQuestion.setItemId(getItemId()); //This will trigger a later UI update of the fragment.
    }
}