Android Navigation Drawer甚至没有调用公共布尔值onNavigationItemSelected

Question

每当我运行这个应用程序时，一切都很好。但当我点击抽屉选项时，什么都不会发生。当我调试时，我意识到onNavigationItemSelected方法甚至没有被系统调用。但是当我在onCreate方法中提交片段事务时，一切都很好。这是activity.java

ublic class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{
DrawerLayout drawerLayout;
ActionBarDrawerToggle toggle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id._toolbar);
setSupportActionBar(toolbar);
NavigationView navigationView = findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
drawerLayout = findViewById(R.id.drawerlayout);
toggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.nav_opened, R.string.nav_closed);
drawerLayout.addDrawerListener(toggle);
Objects.requireNonNull(getSupportActionBar()).setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
displayView(R.id.nav_home);
}
@Override
protected void onPostCreate(@Nullable Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
toggle.syncState();
}
@Override
public void onConfigurationChanged(@NonNull Configuration newConfig) {
super.onConfigurationChanged(newConfig);
toggle.onConfigurationChanged(newConfig);
}
@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
if(toggle.onOptionsItemSelected(item))
return true;
return super.onOptionsItemSelected(item);
}
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
displayView(item.getItemId());
return true;
}
@Override
public void onBackPressed() {
if(drawerLayout.isDrawerOpen(GravityCompat.START))
drawerLayout.closeDrawer(GravityCompat.START);
else
super.onBackPressed();
}
public void displayView(int viewId) {
Fragment fragment = null;
String title = getString(R.string.app_name);
switch (viewId) {
case R.id.nav_home:
//fragment = new HomeFragment();
break;
case R.id.nav_search:
fragment = new SearchFragment();
break;
case R.id.nav_list:
//fragment = new EatenListFragment();
break;
case R.id.nav_graph:
fragment = new SevenDayGraphFragment();
break;
case R.id.nav_settings:
//fragment = new SettingsFragment();
break;
}
if (fragment != null) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame, fragment);
ft.commit();
}
// set the toolbar title
if (getSupportActionBar() != null) {
getSupportActionBar().setTitle(title);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawerlayout);
drawer.closeDrawer(GravityCompat.START);
}
}

这里是活动的xml文件

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.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/drawerlayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:openDrawer="start"
tools:context=".MainActivity">
<include layout="@layout/appbar"
android:layout_height="match_parent"
android:layout_width="match_parent"/>
<com.google.android.material.navigation.NavigationView
android:id="@+id/nav_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start"
app:headerLayout="@layout/nav_header"
app:menu="@menu/activity_main_drawer">
</com.google.android.material.navigation.NavigationView>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent" android:id="@+id/content_frame"/>
<androidx.fragment.app.FragmentContainerView
android:id="@+id/fragment_container_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</androidx.drawerlayout.widget.DrawerLayout>

Answer 1

对于导航抽屉

主要活动.java

public class MainActivity extends AppCompatActivity {
private AppBarConfiguration mAppBarConfiguration;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
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)
.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.main, menu);
return true;
}
@Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}

}布局内

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.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:openDrawer="start">
<include
layout="@layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<com.google.android.material.navigation.NavigationView
android:id="@+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="@layout/nav_header_main"
app:menu="@menu/activity_main_drawer" />
</androidx.drawerlayout.widget.DrawerLayout>

app_bar_main.xml

<?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"
tools:context=".MainActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/Theme.NavigationDrawerApp.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/Theme.NavigationDrawerApp.PopupOverlay" />
</com.google.android.material.appbar.AppBarLayout>
<include layout="@layout/content_main" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
app:srcCompat="@android:drawable/ic_dialog_email" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>

content_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:showIn="@layout/app_bar_main">
<fragment
android:id="@+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="@navigation/mobile_navigation" />
</androidx.constraintlayout.widget.ConstraintLayout>

nav_header_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="@dimen/nav_header_height"
android:background="@drawable/side_nav_bar"
android:gravity="bottom"
android:orientation="vertical"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
android:theme="@style/ThemeOverlay.AppCompat.Dark">
<ImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/nav_header_desc"
android:paddingTop="@dimen/nav_header_vertical_spacing"
app:srcCompat="@mipmap/ic_launcher_round" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="@dimen/nav_header_vertical_spacing"
android:text="@string/nav_header_title"
android:textAppearance="@style/TextAppearance.AppCompat.Body1" />
</LinearLayout>

菜单中

activity_main_drawer.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
tools:showIn="navigation_view">
<group android:checkableBehavior="single">
<item
android:id="@+id/nav_home"
android:icon="@drawable/ic_menu_camera"
android:title="@string/menu_home" />
<item
android:id="@+id/nav_gallery"
android:icon="@drawable/ic_menu_gallery"
android:title="@string/menu_gallery" />
<item
android:id="@+id/nav_slideshow"
android:icon="@drawable/ic_menu_slideshow"
android:title="@string/menu_slideshow" />
</group>
</menu>

Answer 2

由meyself解决。在activity_main.xml文件中，我将NavigationView块放在FrameLayout和FragmentContainerView块下。在网上，大多数人都说把它放在LinearLayout下，但由于我在xml中没有LinearLayout，我认为这对我来说没有意义。