我正在尝试Android Navigation Architecture Component,并且还在研究Material design指南.我真的受到了下面的design的启发:
对于顶部工具栏,我可以通过setSupportActionBar(工具栏)然后在MainActivity中设置它:
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu, menu);
return super.onCreateOptionsMenu(menu);
}
但是在尝试时我无法弄清楚如何在顶部和底部应用栏上为不同的片段实现菜单,特别是对于底部应用栏.
例如,我想在DetailFragment上的底部应用栏上显示一个喜欢的图标,但是在MainActivity上,它应该消失了.
我目前的代码:
主要活动
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
NavController navController = Navigation.findNavController(this, R.id.nav_host);
NavigationUI.setupActionBarWithNavController(this, navController);
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(view -> Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show());
}
@Override
public boolean onSupportNavigateUp() {
return Navigation.findNavController(this, R.id.nav_host).navigateUp();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu, menu);
return super.onCreateOptionsMenu(menu);
}
}
MainFragment
public class MainFragment extends Fragment {
public MainFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_main, container, false);
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Button buttonOne = view.findViewById(R.id.button_one);
buttonOne.setOnClickListener(Navigation.createNavigateOnClickListener(R.id.detailFragment));
}
}
DetailFragment
public class DetailFragment extends Fragment {
public DetailFragment() {
// Required empty public constructor
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_detail, container, false);
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true"
tools:context=".MainActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:theme="@style/AppTheme.AppBarOverlay">
<androidx.appcompat.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</com.google.android.material.appbar.AppBarLayout>
<fragment
android:id="@+id/nav_host"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="top"
android:layout_marginTop="?android:attr/actionBarSize"
app:defaultNavHost="true"
app:layout_anchor="@id/bottom_appbar"
app:layout_anchorGravity="top"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
app:navGraph="@navigation/mobile_navigation" />
<com.google.android.material.bottomappbar.BottomAppBar
android:id="@+id/bottom_appbar"
android:layout_width="match_parent"
android:layout_height="?android:attr/actionBarSize"
android:layout_gravity="bottom" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_anchor="@id/bottom_appbar" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
mobile_navigation.xml
<navigation 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/mobile_navigation"
app:startDestination="@id/mainFragment">
<fragment
android:id="@+id/mainFragment"
android:name="com.example.MainFragment"
android:label="fragment_main"
tools:layout="@layout/fragment_main" >
<action
android:id="@+id/toAccountFragment"
app:destination="@id/detailFragment" />
</fragment>
<fragment
android:id="@+id/detailFragment"
android:name="com.example.DetailFragment"
android:label="fragment_account"
tools:layout="@layout/fragment_detail" />
</navigation>
menu.xml文件
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="@+id/app_bar_settings"
android:title="@string/action_settings"
app:showAsAction="never" />
</menu>
仅适用于DetialFragment的bottom_appbar_menu.xml
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="@+id/action_bottom_fav"
android:icon="@drawable/ic_favorite"
android:title="@string/action_favorite"
app:showAsAction="ifRoom" />
</menu>
任何帮助表示赞赏.
更新可能的解决方案:
这是我能够想到的,但不满意,因为我不知道这是否是写它的方式.我发布了一个可能的解决方案:
1- MainActivity
NavController navController = Navigation.findNavController(this, R.id.nav_host);
NavigationUI.setupWithNavController(toolbar, navController);
2-为底部应用栏创建两个不同的菜单(我没有尝试动态添加菜单项),一个用于MainFragment的空白菜单xml,另一个包含DetailFragment的收藏夹图标.
为简单起见,在MainActivity中覆盖onCreateOptionsMenu而不是使用MainFragment覆盖它:
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu, menu);
bottomAppBar.replaceMenu(R.menu.bottom_menu_blank);
return super.onCreateOptionsMenu(menu);
}
3-感谢@ʍѳђઽ૯ท,让我知道Bottom App Bar的replaceMenu方法.在DetailFragment中使用setHasOptionsMenu(true)并覆盖onCreateOptionsMenu:
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
BottomAppBar bottomAppBar = requireActivity().findViewById(R.id.bottom_appbar);
bottomAppBar.replaceMenu(R.menu.bottom_menu_fav);
}
如果有人有更好的方法,请告诉我们.
解决方法:
像往常一样使用onCreateOptionsMenu()作为工具栏:(Kotlin)
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.menu_first, menu)
return super.onCreateOptionsMenu(menu)
}
然后在onCreate()中声明工具栏并使用setSupportActionBar():
val toolbar = findViewById<Toolbar>(R.id.myToolbar)
setSupportActionBar(toolbar)
之后,replaceMenu()会做到这一点:(在onCreate()中)
val bottomBar = findViewById<BottomAppBar>(R.id.bottomAppBar)
bottomBar.replaceMenu(R.menu.menu_main)
请注意,如果您想将BottomSheetFragment用于NavigationView开放,则需要setSupportActionBar才能设置BottomAppBar的菜单,我仍然无法找到解决此问题的方法.