Java 在Android中单击backbutton时如何填充片段抽屉列表
我正在尝试制作一个Android功能，允许用户单击其中一个片段内的“后退按钮”，以便显示片段抽屉列表。虽然此功能（填充列表视图）已通过单击homeup按钮实现，但用户有时可以只单击back按钮，并希望确保显示碎片抽屉 代码的结构如下所示。 我有一个扩展ActionbarActivity并实现NavigationDrawerFragment类的主活动类 NavigationDrawerFragment具有打开或关闭抽屉的功能。在这里，我不知道如何访问“NavigationDrawerFragment类”中的抽屉函数 我的目标是，在主要活动中Java 在Android中单击backbutton时如何填充片段抽屉列表,java,android,android-fragments,Java,Android,Android Fragments,我正在尝试制作一个Android功能，允许用户单击其中一个片段内的“后退按钮”，以便显示片段抽屉列表。虽然此功能（填充列表视图）已通过单击homeup按钮实现，但用户有时可以只单击back按钮，并希望确保显示碎片抽屉 代码的结构如下所示。 我有一个扩展ActionbarActivity并实现NavigationDrawerFragment类的主活动类 NavigationDrawerFragment具有打开或关闭抽屉的功能。在这里，我不知道如何访问“NavigationDrawerFragmen
@Override
public void onBackPressed() {
drawershow();
}
public class MainActivity extends ActionBarActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks {
private static final String TAG = MainActivity.class.getName();
private NavigationDrawerFragment mNavigationDrawerFragment;
private CharSequence mTitle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainactivity2);
final String intent_message = getIntent().getStringExtra("message");
if (intent_message!= null){
Toast.makeText(getApplicationContext(), intent_message, Toast.LENGTH_LONG).show();
}
mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
@Override
public void onNavigationDrawerItemSelected(int position) {
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
Fragment fragmentToLaunch = getFragmentToLaunch(position);
fragmentManager.beginTransaction()
.replace(R.id.container, fragmentToLaunch)
.commit();
}
public void onSectionAttached(int number) {
switch (number) {
case CASE_SECTION_VIDEO_CALL:
mTitle = getString(R.string.title_section1);
break;
default:
break;
}
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setTitle(mTitle);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
getMenuInflater().inflate(R.menu.main, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_build_info) {
String versionInfo = "SDK Version: " + sg.com.temasys.skylink.sdk.BuildConfig.VERSION_NAME
+ "\n" + "Sample application version: " + BuildConfig.VERSION_NAME;
Log.d(TAG, versionInfo);
return true;
}
return super.onOptionsItemSelected(item);
}
public Fragment getFragmentToLaunch(int position) {
Fragment fragmentToLaunch = null;
switch (position) {
case CASE_FRAGMENT_VIDEO_CALL:
fragmentToLaunch = new VideoCallFragment();
break;
}
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, position + 1);
fragmentToLaunch.setArguments(args);
return fragmentToLaunch;
}
@Override
public void onBackPressed() {
here!
}
}
public class NavigationDrawerFragment extends Fragment {
private NavigationDrawerCallbacks mCallbacks;
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private ListView mDrawerListView;
private View mFragmentContainerView;
private int mCurrentSelectedPosition = 0;
private boolean mFromSavedInstanceState;
private boolean mUserLearnedDrawer;
public NavigationDrawerFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
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) {
mDrawerListView = (ListView) inflater.inflate(
R.layout.fragment_navigation_drawer, container, false);
mDrawerListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
selectItem(position);
}
});
mDrawerListView.setAdapter(new ArrayAdapter<String>(
getActionBar().getThemedContext(),
// android.R.layout.simple_list_item_activated_1,
R.layout.simple_list_item_activated_sungpah,
android.R.id.text1,
new String[]{
....
}));
mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
return mDrawerListView;
}
public boolean isDrawerOpen() {
return mDrawerLayout != null && mDrawerLayout.isDrawerOpen(mFragmentContainerView);
}
public void setUp(int fragmentId, DrawerLayout drawerLayout) {
mFragmentContainerView = getActivity().findViewById(fragmentId);
mDrawerLayout = drawerLayout;
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
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(
/* host Activity */
getActivity(),
/* DrawerLayout object */
mDrawerLayout,
/* nav drawer image to replace 'Up' caret */
R.drawable.ic_drawer,
/* "open drawer" description for accessibility */
R.string.navigation_drawer_open,
/* "close drawer" description for accessibility */
R.string.navigation_drawer_close
) {
@Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
if (!isAdded()) {
return;
}
// calls onPrepareOptionsMenu()
getActivity().supportInvalidateOptionsMenu();
}
@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();
}
// calls onPrepareOptionsMenu()
getActivity().supportInvalidateOptionsMenu();
}
};
if (!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) {
//0,1,2,3
//1 => my class.(video call)
mCurrentSelectedPosition = position; //<-- save as an integer.
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) {
Log.e("TAG", e.getMessage(), 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.main, menu);
showGlobalContextActionBar();
}
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
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);
actionBar.setTitle(R.string.app_name);
}
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);
}
}
公共类NavigationDrawerFragment扩展片段{
专用导航抽屉回调mCallbacks；
私有操作bardrawertoggle mDrawerToggle；
私人抽屉布局mDrawerLayout；
私有列表视图mDrawerListView；
私有视图MFFragmentContainerView；
private int mCurrentSelectedPosition=0；
私有布尔值mFromSavedInstanceState；
私有布尔mUserLearnedDrawer；
公共导航抽屉碎片（）{
}
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
SharedReferences sp=PreferenceManager.GetDefaultSharedReferences（getActivity（））；
mUserLearnedDrawer=sp.getBoolean（预用户已学习抽屉，false）；
如果（savedInstanceState！=null）{
mCurrentSelectedPosition=savedInstanceState.getInt（STATE\u SELECTED\u POSITION）；
mFromSavedInstanceState=true；
}
//选择默认项（0）或最后选定的项。
selectItem（mCurrentSelectedPosition）；
}
@凌驾
已创建ActivityState上的公共无效（Bundle savedInstanceState）{
super.onActivityCreated（savedInstanceState）；
//指示此片段希望影响操作栏中的操作集。
设置选项菜单（真）；
}
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
mDrawerListView=（ListView）充气器。充气(
R.layout.fragment_导航_抽屉、容器、假）；
mDrawerListView.setOnItemClickListener（新的AdapterView.OnItemClickListener（）{
@凌驾
public void onItemClick（AdapterView父对象、视图、整型位置、长id）{
选择项目（位置）；
}
});
mDrawerListView.setAdapter（新阵列适配器）(
getActionBar（）.getThemedContext（），
//android.R.layout.simple\u list\u item\u activated\u 1，
R.layout.simple\u list\u item\u activated\u sungpah，
android.R.id.text1，
新字符串[]{
....
}));
mDrawerListView.setItemChecked（mCurrentSelectedPosition，true）；
返回mDrawerListView；
}
公共布尔值isDrawerOpen（）{
返回mDrawerLayout！=null&&mDrawerLayout.isDrawerOpen（MFFragmentContainerView）；
}
公共空白设置（int fragmentId、抽屉布局抽屉布局）{
MFFragmentContainerView=getActivity（）.findViewById（fragmentId）；
mDrawerLayout=抽屉式布局；
mDrawerLayout.setDrawerShadow（R.drawable.drawer\u shadow，GravityCompat.START）；
ActionBar ActionBar=getActionBar（）；
actionBar.setDisplayHomeAsUpEnabled（true）；
actionBar.setHomeButtonEnabled（真）；
//ActionBarDrawerToggle将适当的交互连接在一起
//在导航抽屉和操作栏应用程序图标之间。
mDrawerToggle=新操作bardrawertoggle(
/*宿主活动*/
getActivity（），
/*抽屉布局对象*/
mDrawerLayout，
/*导航抽屉图像替换“向上”插入符号*/
R.可抽出式ic_抽屉，
/*可访问性的“打开抽屉”说明*/
R.string.navigation\u抽屉\u打开，
/*可访问性的“关闭抽屉”说明*/
R.string.navigation\u drawer\u close
) {
@凌驾
图纸上的公共空白已关闭（视图抽屉视图）{
super.onDrawerClosed（抽屉视图）；
如果（！isAdded（））{
返回；
}
//调用PrepareOptions功能表（）
getActivity（）.SupportInvalidateOptions菜单（）；
}
@凌驾
打开图纸上的公共空白（视图抽屉视图）{
super.onDrawerOpened（抽屉视图）；
如果（！isAdded（））{
返回；
}
如果（！mUserLearnedDrawer）{
//用户手动打开抽屉；存储此标志以防止自动显示
//导航抽屉将来会自动打开。
mUserLearnedDrawer=真；
SharedReferences sp=首选项管理器
.GetDefaultSharedReferences（getActivity（））；
sp.edit（）.putBoolean（PREF_USER_learn_DRAWER，true）.apply（）；
}
//调用PrepareOptions功能表（）
getActivity（）.SupportInvalidateOptions菜单（）；
}
};
如果（！mFromSavedInstanceState）{
mDrawerLayout.openDrawer（MFFragmentContainerView）；
}
//根据先前实例状态的恢复延迟代码。
mDrawerLayout.post（新的Runnable（）{
@凌驾
公开募捐{
mDrawerToggle.syncState（）；
}