Android 如何从所有其他片段导航到特定片段?
当我从Home_片段按back按钮时,控件将转到一个空页面,当我从Home_片段按back按钮时,我想退出我的应用程序,同时当我从所有其他片段按back按钮时,我想导航到Home_片段。我的主要活动页面在下面Android 如何从所有其他片段导航到特定片段?,android,android-fragments,android-activity,Android,Android Fragments,Android Activity,当我从Home_片段按back按钮时,控件将转到一个空页面,当我从Home_片段按back按钮时,我想退出我的应用程序,同时当我从所有其他片段按back按钮时,我想导航到Home_片段。我的主要活动页面在下面 public class MainActivity extends ActionBarActivity implements FragmentDrawer.FragmentDrawerListener { private static String TAG = MainActivit
public class MainActivity extends ActionBarActivity implements FragmentDrawer.FragmentDrawerListener {
private static String TAG = MainActivity.class.getSimpleName();
private Toolbar mToolbar;
private FragmentDrawer drawerFragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(mToolbar);
getSupportActionBar().setDisplayShowHomeEnabled(true);
drawerFragment = (FragmentDrawer)
getSupportFragmentManager().findFragmentById(R.id.fragment_navigation_drawer);
drawerFragment.setUp(R.id.fragment_navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout), mToolbar);
drawerFragment.setDrawerListener(this);
// display the first navigation drawer view on app launch
displayView(0);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
if(id == R.id.action_search){
Toast.makeText(getApplicationContext(), "Search action is selected!", Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onDrawerItemSelected(View view, int position) {
displayView(position);
}
private void displayView(int position) {
Fragment fragment = null;
String title = getString(R.string.app_name);
switch (position) {
case 0:
fragment = new HomeFragment();
title = getString(R.string.title_home);
break;
case 1:
fragment = new FriendsFragment();
title = getString(R.string.title_friends);
break;
case 2:
fragment = new MessagesFragment();
title = getString(R.string.title_messages);
break;
default:
break;
}
if (fragment != null) {
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
// set the toolbar title
getSupportActionBar().setTitle(title);
}
}
}您可以为onBackButton编写代码,以检查
backbackbackentry的计数。如果其中至少有一个碎片,则计数将大于0。
如果count==0
则执行finish()
您可以为onBackButton编写代码,以检查backbackbackentry
的计数。如果其中至少有一个碎片,则计数将大于0。
如果count==0
则执行finish()
你可以试试这个,它很有效:
在主活动中创建一个方法以调用片段:
public void replaceFragment(Fragment fragmentName){
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragmentName);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
并通过以下代码行通过任何片段调用此方法:-
((MainActivity)getActivity).replaceFragment(FragmentName.class)
你可以试试这个,它很有效:
在主活动中创建一个方法以调用片段:
public void replaceFragment(Fragment fragmentName){
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragmentName);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
并通过以下代码行通过任何片段调用此方法:-
((MainActivity)getActivity).replaceFragment(FragmentName.class)
只需在每个片段中重写OnBackbuttPressed方法即可删除这一行fragmentTransaction.addToBackStack(null);当我按下后退按钮时,如果我删除fragmentTransaction,应用程序也将从所有其他片段中退出。addToBackStack(null)只需覆盖每个片段中的OnBackbuttPressed方法即可删除此行fragmentTransaction。addToBackStack(null);当我按下“后退”按钮时,如果我删除fragmentTransaction,应用程序将从所有其他片段中退出。addToBackStack(null)哦,对不起,它是1。当我现在想到数字的时候。我总是以0开头。程序员。LOL剩下的问题是,当我按下所有其他片段的后退按钮时,我想导航到Home_片段,现在它转到我在当前片段之前选择的上一个片段。你必须阅读谷歌文档,哦,对不起,它是1。当我现在想到数字的时候。我总是以0开头。程序员。LOL剩下的问题是,当我按下所有其他片段的后退按钮时,我想导航到Home_片段,现在转到我在当前片段之前选择的上一个片段。你也需要阅读谷歌文档