Android 如何从另一个片段访问片段对象
我有一个导航抽屉活动(主管仪表板),其中有一个包含recyclerview的片段(工作人员详细信息) 在同一个活动中,我有一个显示排序选项的底部工作表片段 现在,我想将用户选择的排序选项应用到RecyclerViewAndroid 如何从另一个片段访问片段对象,android,android-studio,android-fragments,android-recyclerview,fragment,Android,Android Studio,Android Fragments,Android Recyclerview,Fragment,我有一个导航抽屉活动(主管仪表板),其中有一个包含recyclerview的片段(工作人员详细信息) 在同一个活动中,我有一个显示排序选项的底部工作表片段 现在,我想将用户选择的排序选项应用到RecyclerView Activity -> Fragment1 (worker details) -> RecyclerView -> RecyclerViewAdapter
Activity -> Fragment1 (worker details) -> RecyclerView
-> RecyclerViewAdapter
-> RecyclerViewModel
-> Fragment2 (bottom sheet) -> Sort options
那么,如何访问Fragment1的RecyclerView对象并从Fragment2中的onClick对适配器的数组进行排序呢
现在,我已经可以使用
(SupervisorDashboard)getActivity()).method()
但如何从主机活动访问Fragment1的RecyclerView对象?
员工详细信息
public class WorkerDetailsFragment extends Fragment {
private WorkerDetailsViewModel workerDetailsViewModel;
static RecyclerView recyclerView;
public View onCreateView(@NonNull LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
workerDetailsViewModel = ViewModelProviders.of(this).get(WorkerDetailsViewModel.class);
View root = inflater.inflate(R.layout.fragment_worker_details, container, false);
recyclerView = root.findViewById(R.id.rc_worker_details);
WorkerRVAdapter workerRVAdapter = new WorkerRVAdapter(
workerDetailsViewModel.getWorkerNames(),
workerDetailsViewModel.getWorkerRoles(),
workerDetailsViewModel.getImageUrls(),
getContext());
recyclerView.setNestedScrollingEnabled(false);
recyclerView.setAdapter(workerRVAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
return root;
}
}
监管者仪表板
public class SupervisorDashboard extends AppCompatActivity {
private AppBarConfiguration mAppBarConfiguration;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_supervisor_dashboard);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = findViewById(R.id.drawer_layout);
NavigationView navigationView = findViewById(R.id.nav_view);
// Passing each menu ID as a set of Ids because each
// menu should be considered as top level destinations.
mAppBarConfiguration = new AppBarConfiguration.Builder(
R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow,
R.id.nav_tools, R.id.nav_share, R.id.nav_send)
.setDrawerLayout(drawer)
.build();
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
NavigationUI.setupWithNavController(navigationView, navController);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.supervisor_dashboard, menu);
return true;
}
@Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_settings:
View view = getLayoutInflater().inflate(R.layout.fragment_bottom_sheet_sort, null);
// BottomSheetDialog dialog = new BottomSheetDialog(this);
// dialog.setContentView(view);
// dialog.show();
BottomSheetSortFragment bottomSheetFragment = new BottomSheetSortFragment();
bottomSheetFragment.show(getSupportFragmentManager(), "hello");
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
底部挡板或碎片
public View onCreateView(LayoutInflater inflater, final ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_bottom_sheet_sort, container, false);
button = view.findViewById(R.id.apply_button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// Sort the arrays in RecyclerView on click
dismiss();
}
});
return view;
}
我可以在Fragment2中创建一个静态方法,然后从Fragment1中调用该方法,但必须有一些正确的方法来实现它。示例片段
public class SomeFragment extends Fragment {
public View view;
public TextView textView;
public Button button;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view =inflater.inflate(R.layout.fragment_blank, container, false);
textView = (TextView)view.getRootView().findViewById(R.id.textView_fragment1);
return view;
}
public void getTextView(){
return textView;
}
public void getButton(){
return button;
}
一旦在MainActivity或任何其他您想要访问
TextView/按钮,您应该确保在中设置片段
您的OnCreate()方法可能会以其他方式抛出null指针。
因此,您想要更改TextView/按钮的活动应该如下所示:
public class MainActivity extends AppCompatActivity {
private Button button1;
private FragmentManager fragmentManager;
private FragmentTransaction fragmentTransaction;
SomeFragment someFragment = new SomeFragment();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1 = (Button)findViewById(R.id.button1);
changeFragment();
fragmentManager = getFragmentManager();
fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.fragment1,someFragment);
fragmentTransaction.commit();
// Now we can get access to TextView and Button inside SomeFragment
}
public void updateText(String msg) {
TextView v = this.someFragment.getTextView();
v.setText(msg);
}
} // end of activity
但如何从主机活动访问Fragment1的RecyclerView对象
理想情况下,你不会。您在Fragment1中公开了一个方法,该方法定义了您要执行的操作,然后根据需要在活动中调用该方法
文档介绍了如何在片段之间进行通信:
只要调用活动的方法,我就可以从片段中通知宿主活动。是否有任何方法可以访问主机活动中片段的对象(回收器视图)?用示例更新了我的答案。请检查。您能指定我们如何调用片段类方法getTextView()吗?我在活动类中添加了一个updateText()方法。从这里我调用fragment的getTextView()方法。