我有NavigationDrawerFragment的活动，如下所示：
NavigationDrawerFragment.java
/**
* Fragment used for managing interactions for and presentation of a navigation drawer.
* See the <a href="https://developer.android.com/design/patterns/navigation-drawer.html#Interaction">
* design guidelines</a> for a complete explanation of the behaviors implemented here.
*/
public class NavigationDrawerFragment extends Fragment {
/**
* Remember the position of the selected item.
*/
private static final String STATE_SELECTED_POSITION = "selected_navigation_drawer_position";
/**
* Per the design guidelines, you should show the drawer on launch until the user manually
* expands it. This shared preference tracks this.
*/
private static final String PREF_USER_LEARNED_DRAWER = "navigation_drawer_learned";
/**
* A pointer to the current callbacks instance (the Activity).
*/
private NavigationDrawerCallbacks mCallbacks;
/**
* Helper component that ties the action bar to the navigation drawer.
*/
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private ListView mDrawerListView;
private View mFragmentContainerView;
private int mCurrentSelectedPosition = 0;
private boolean mFromSavedInstanceState;
private boolean mUserLearnedDrawer;
private EventActivity mainActivity = null;
public NavigationDrawerFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Read in the flag indicating whether or not the user has demonstrated awareness of the
// drawer. See PREF_USER_LEARNED_DRAWER for details.
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(getActivity());
mUserLearnedDrawer = sp.getBoolean(PREF_USER_LEARNED_DRAWER, false);
if (savedInstanceState != null) {
mCurrentSelectedPosition = savedInstanceState.getInt(STATE_SELECTED_POSITION);
mFromSavedInstanceState = true;
}
// Select either the default item (0) or the last selected item.
selectItem(mCurrentSelectedPosition);
}
@Override
public void onActivityCreated (Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// Indicate that this fragment would like to influence the set of actions in the action bar.
setHasOptionsMenu(true);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
mainActivity = (EventActivity) getActivity();
mFragmentContainerView = inflater.inflate(R.layout.fragment_drawer_attendee, container, false);
... NOT IMPORTANT ...
mDrawerListView.setAdapter(new MenuEventAdapter(getActivity(), menuAL));
mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
mDrawerListView.setOnItemClickListener(new OnItemClickListener()
{
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id)
{
... NOT IMPORTANT ...
}
});
return mFragmentContainerView;
}
public boolean isDrawerOpen() {
return mDrawerLayout != null && mDrawerLayout.isDrawerOpen(mFragmentContainerView);
}
/**
* Users of this fragment must call this method to set up the navigation drawer interactions.
*
* @param fragmentId The android:id of this fragment in its activity's layout.
* @param drawerLayout The DrawerLayout containing this fragment's UI.
*/
public void setUp(int fragmentId, DrawerLayout drawerLayout) {
mFragmentContainerView = getActivity().findViewById(fragmentId);
mDrawerLayout = drawerLayout;
// set a custom shadow that overlays the main content when the drawer opens
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
// set up the drawer's list view with items and click listener
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeButtonEnabled(true);
// ActionBarDrawerToggle ties together the the proper interactions
// between the navigation drawer and the action bar app icon.
mDrawerToggle = new ActionBarDrawerToggle(
getActivity(), /* host Activity */
mDrawerLayout, /* DrawerLayout object */
R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */
R.string.navigation_drawer_open, /* "open drawer" description for accessibility */
R.string.navigation_drawer_close /* "close drawer" description for accessibility */
) {
@Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
if (!isAdded()) {
return;
}
getActivity().supportInvalidateOptionsMenu(); // calls onPrepareOptionsMenu()
}
@Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
if (!isAdded()) {
return;
}
if (!mUserLearnedDrawer) {
// The user manually opened the drawer; store this flag to prevent auto-showing
// the navigation drawer automatically in the future.
mUserLearnedDrawer = true;
SharedPreferences sp = PreferenceManager
.getDefaultSharedPreferences(getActivity());
sp.edit().putBoolean(PREF_USER_LEARNED_DRAWER, true).apply();
}
getActivity().supportInvalidateOptionsMenu(); // calls onPrepareOptionsMenu()
}
};
// If the user hasn't 'learned' about the drawer, open it to introduce them to the drawer,
// per the navigation drawer design guidelines.
if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
mDrawerLayout.openDrawer(mFragmentContainerView);
}
// Defer code dependent on restoration of previous instance state.
mDrawerLayout.post(new Runnable() {
@Override
public void run() {
mDrawerToggle.syncState();
}
});
mDrawerLayout.setDrawerListener(mDrawerToggle);
}
private void selectItem(int position) {
mCurrentSelectedPosition = position;
if (mDrawerListView != null) {
mDrawerListView.setItemChecked(position, true);
}
if (mDrawerLayout != null) {
mDrawerLayout.closeDrawer(mFragmentContainerView);
}
if (mCallbacks != null) {
mCallbacks.onNavigationDrawerItemSelected(position);
}
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mCallbacks = (NavigationDrawerCallbacks) activity;
} catch (ClassCastException e) {
throw new ClassCastException("Activity must implement NavigationDrawerCallbacks.");
}
}
@Override
public void onDetach() {
super.onDetach();
mCallbacks = null;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt(STATE_SELECTED_POSITION, mCurrentSelectedPosition);
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Forward the new configuration the drawer toggle component.
mDrawerToggle.onConfigurationChanged(newConfig);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
// If the drawer is open, show the global app actions in the action bar. See also
// showGlobalContextActionBar, which controls the top-left area of the action bar.
if (mDrawerLayout != null && isDrawerOpen()) {
inflater.inflate(R.menu.global, menu);
showGlobalContextActionBar();
}
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
/*if (item.getItemId() == R.id.action_example) {
Toast.makeText(getActivity(), "Example action.", Toast.LENGTH_SHORT).show();
return true;
}
*/
return super.onOptionsItemSelected(item);
}
/**
* Per the navigation drawer design guidelines, updates the action bar to show the global app
* 'context', rather than just what's in the current screen.
*/
private void showGlobalContextActionBar() {
ActionBar actionBar = getActionBar();
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
}
private ActionBar getActionBar() {
return ((ActionBarActivity) getActivity()).getSupportActionBar();
}
/**
* Callbacks interface that all activities using this fragment must implement.
*/
public static interface NavigationDrawerCallbacks {
/**
* Called when an item in the navigation drawer is selected.
*/
void onNavigationDrawerItemSelected(int position);
}
}
当我从抽屉中选择一个项目时，它会向活动容器中添加一个新的Fragment。
每个片段都有自己的菜单，如下例所示：
EventInformationFragment.java
public class EventInformationFragment extends Fragment
{
private View rootView = null;
private EventActivity mainActivity = null;
private GoogleMap mMap;
private boolean isStaff = false;
private LayoutInflater inflater = null;
private ViewGroup container = null;
private TextView forCopy = null;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
if(EventActivityHelper.getHelper().inSchedule)
{
return null;
}
mainActivity = (EventActivity) GlobalContents.getNowActivity();
mainActivity.getActionBar().setTitle(R.string.Event);
this.inflater = inflater;
this.container = container;
GlobalContents.dismissProgressBar();
if(!GlobalContents.getGlobalContents().getAuthenticatedUser().isStaff())
{
return elaborateAttendeeView();
}
isStaff = true;
return elaborateStaffView();
}
private View elaborateAttendeeView()
{
... NOT IMPORTANT ...
}
private View elaborateStaffView()
{
... NOT IMPORTANT ...
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
if(menu.hasVisibleItems())
menu.clear();
if(isStaff)
inflater.inflate(R.menu.event, menu);
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public void onPrepareOptionsMenu(Menu menu)
{
if(menu.hasVisibleItems())
menu.clear();
MenuInflater inflater = getActivity().getMenuInflater();
if(isStaff)
inflater.inflate(R.menu.event, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case R.id.action_edit:
mainActivity.getSupportFragmentManager()
.beginTransaction()
.remove(mainActivity.currentFragment)
.remove(getFragmentManager().findFragmentById(R.id.map))
.commit();
mainActivity.currentFragment = new EventEditInformationFragment();
mainActivity.getSupportFragmentManager().beginTransaction()
.add(R.id.container, mainActivity.currentFragment).commit();
break;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo)
{
... NOT IMPORTANT ...
}
@Override
public boolean onContextItemSelected(MenuItem item)
{
... NOT IMPORTANT ...
}
}
以下是EventInformationFragment的确切部分，我将菜单膨胀：
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
if(menu.hasVisibleItems())
menu.clear();
if(isStaff)
inflater.inflate(R.menu.event, menu);
super.onCreateOptionsMenu(menu, inflater);
}
问题是：当我通过Fragment打开NavigationDrawerFragment时，菜单不会膨胀！
在EventInformationFragment中，我打算开展其他活动，并且 onResume 此活动，菜单会膨胀！
我做错了什么？
以下是包含NavigationDrawerFragment的活动，在某些时候，EventInformationFragment
EventActivity.java
public class EventActivity extends ActionBarActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks
{
private static final String TAG = "EventActivity";
private NavigationDrawerFragment mNavigationDrawerFragment;
public Event currentEvent = null;
private PagerSlidingTabStrip tabs;
private ViewPager pager;
/* FOR TABBING */
private MyPagerAdapter adapter;
public Fragment currentFragment = null;
public Map<String, Fragment> fragments = null;
private Bundle instance;
public Vector<List<Lecture>> currentLectures = null;
private Calendar[] realScheduleDays;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_with_fragment_and_drawer);
currentEvent = GlobalContents.getGlobalContents().getCurrentEvent();
GlobalContents.setNowActivity(this);
if(GlobalContents.getGlobalContents().getAuthenticatedUser() == null)
{
Intent intent = new Intent(this, SignInActivity.class);
startActivity(intent);
finish();
}
else if(currentEvent == null)
{
Intent intent = new Intent(this, ProfileEventActivity.class);
startActivity(intent);
finish();
}
else
{
GlobalContents.getGlobalContents().setProgressBar();
/* DRAWER */
mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager()
.findFragmentById(R.id.navigation_drawer);
DrawerLayout mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
setTitle(getString(R.string.Event));
mNavigationDrawerFragment.setUp(R.id.navigation_drawer, mDrawerLayout);
if(!EventActivityHelper.getHelper().inSchedule)
dismissTabsForSchedule();
else
loadTabsForSchedule();
/* CONTENT */
if (savedInstanceState == null)
{
EventActivityHelper.getHelper();
if(!EventActivityHelper.getHelper().inSchedule)
{
currentFragment = new EventInformationFragment();
fragments = new HashMap<String, Fragment>();
fragments.put(currentFragment.getClass().getName(), currentFragment);
getSupportFragmentManager().beginTransaction()
.add(R.id.container, currentFragment).commit();
}
}
}
}
public void loadTabsForSchedule()
{
... NOT IMPORTANT ...
}
public void dismissTabsForSchedule()
{
... NOT IMPORTANT ...
}
@Override
public void onNavigationDrawerItemSelected(int position) {
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
/*fragmentManager
.beginTransaction()
.replace(R.id.container,
PlaceholderFragment.newInstance(position + 1)).commit();*/
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
//getMenuInflater().inflate(R.menu.event, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
return super.onOptionsItemSelected(item);
}
@Override
protected void onResume()
{
super.onResume();
GlobalContents.setNowActivity(this);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
GlobalContents.setNowActivity(this);
switch(requestCode)
{
case Constants.FOR_REFRESH:
if(resultCode == Constants.FOR_REFRESH_OK)
{
currentLectures = null;
loadTabsForSchedule();
}
break;
}
}
... NOT IMPORTANT FROM NOW ON...
}
答案 0 :(得分：0)
经过大量的搜索和尝试，我已经设法让它发挥作用。
在我提交Fragment之前，我已经放置了invalidateOptionsMenu()。
现在有效。