我使用抽屉布局作为我的活动基础布局,并在这个抽屉布局内的帧上替换了两个片段。第一个片段没有添加到片段的后退栈中。我在我的活动中显示汉堡图标(我还想在我的第一个片段中显示抽屉菜单)。在第二个片段中,我通过
第二个片段
mActionBarDrawerToggle.setDrawerIndicatorEnabled(false)
禁用了汉堡图标,并使用actionBar.setDisplayHomeAsUpEnabled(true)
启用了返回按钮。
在第一个片段的onResume中,我通过mActionBarDrawerToggle.setDrawerIndicatorEnabled(true)启用了汉堡图标,以便当用户从第二个片段按下返回按钮(硬件和操作栏的向上按钮)回到第一个片段时,汉堡图标将被启用。一切都很好,只是我无法从第二个片段的操作栏返回按钮返回。我无法点击它。 以下是我的代码:
活动代码
if (Utility.isLargeScreen(this))
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
else
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
mHiddenGemsApplication = (HiddenGemsApplication) getApplication();
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
initViews();
setSupportActionBar(mToolbar);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayHomeAsUpEnabled(true);
}
mTextViewActionBarTitle.setText(getString(R.string.app_name));
mActionBarDrawerToggle = new ActionBarDrawerToggle(HomeActivity.this, mDrawerLayout, mToolbar, R.string.open_drawer, R.string.close_drawer) {
@Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
}
@Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
}
};
mDrawerLayout.setDrawerListener(mActionBarDrawerToggle);
mActionBarDrawerToggle.syncState();
mFragmentManager = getSupportFragmentManager();
replaceFragment(new CategoryFragment(), getString(R.string.app_name), CategoryFragment.TAG);
@Override
public void onBackPressed() {
if (mDrawerLayout.isDrawerOpen(GravityCompat.START)) {
mDrawerLayout.closeDrawers();
return;
}
super.onBackPressed();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
if (mFragmentManager.getBackStackEntryCount() > 0) {
mFragmentManager.popBackStack();
}
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void replaceFragment(Fragment fragment, String actionBarTitle, String tag) {
if (mFragmentManager == null)
return;
FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.content_frame, fragment, tag);
if (!tag.equals(CategoryFragment.TAG))
fragmentTransaction.addToBackStack(tag);
fragmentTransaction.commit();
setActionBarTitle(actionBarTitle);
}
public void setActionBarTitle(String actionBarTitle) {
if (!TextUtils.isEmpty(actionBarTitle))
mTextViewActionBarTitle.setText(actionBarTitle);
}
public void setDrawerIndicatorEnabled(boolean value) {
if (mActionBarDrawerToggle != null) {
mActionBarDrawerToggle.setDrawerIndicatorEnabled(value);
}
}
活动XML
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="nirvaniclabs.com.hiddengems.activities.HomeActivity">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<include
android:id="@+id/toolbarlayout"
layout="@layout/toolbar_layout" />
<FrameLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@id/toolbarlayout" />
</RelativeLayout>
<android.support.design.widget.NavigationView
android:id="@+id/navigation"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
app:menu="@menu/navigation_items" />
</android.support.v4.widget.DrawerLayout>
第一部分:
private Button mButtonTemp;
private AppCompatActivity mActivity;
public static String TAG = "CategoryFragment";
public CategoryFragment() {
// Required empty public constructor
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof Activity)
mActivity = (AppCompatActivity) context;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View viewGroup = inflater.inflate(R.layout.fragment_category, container, false);
initViews(viewGroup);
mButtonTemp.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
((HomeActivity) mActivity).replaceFragment(new TripListFragment(), "Trip Fragment", TripListFragment.TAG);
}
});
return viewGroup;
}
private void initViews(View viewGroup) {
mButtonTemp = (Button) viewGroup.findViewById(R.id.btn_temp);
}
@Override
public void onResume() {
super.onResume();
((HomeActivity) mActivity).setDrawerIndicatorEnabled(true);
((HomeActivity) mActivity).setActionBarTitle(getString(R.string.app_name));
}
第二个片段
private AppCompatActivity mActivity;
public static String TAG = "TripListFragment";
public TripListFragment() {
// Required empty public constructor
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof Activity)
mActivity = (AppCompatActivity) context;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
ActionBar actionBar = mActivity.getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_trip_list, container, false);
}
@Override
public void onResume() {
super.onResume();
((HomeActivity) mActivity).setDrawerIndicatorEnabled(false);
}
另外,在第二个片段中,我能够滑动并查看抽屉菜单。我不想有这种行为,抽屉菜单应该只在第一个片段中打开。
如果我的代码有任何问题,请告诉我。