如何使菜单项可点击

Question

我正在尝试在应用程序中设置导航活动。问题是我无法在菜单片段之间切换。看起来菜单项是不可点击的。

我试着用以前设置菜单(操作栏)的方法设置导航活动，但它不起作用。同样，对于Click Listener，项目不会做出反应。我现在的问题是如何使onNavigationItemSelected()方法发挥作用？

抱歉代码太多了。

public class NavActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{
private AppBarConfiguration mAppBarConfiguration;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nav);
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);
Toolbar myToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(myToolbar);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.nav, 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 onNavigationItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.nav_home: {
Toast.makeText(NavActivity.this, "Anmeldung Fehlgeschlagen", Toast.LENGTH_LONG).show();
return true;
}
case R.id.nav_gallery:
// User chose the "Favorite" action, mark the current item
// as a favorite...
return true;
}
return super.onOptionsItemSelected(item);
}

app_bar_nav.xml

<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=".NavActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
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>
<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"
android:clickable="true"
app:srcCompat="@android:drawable/ic_dialog_email" />
<include layout="@layout/content_nav" />

activity_nav_drawer.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:App="http://schemas.android.com/apk/res-auto"
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"
android:clickable="true"/>
<item
android:id="@+id/nav_gallery"
android:icon="@drawable/ic_menu_gallery"
android:title="@string/menu_gallery"
android:clickable="true"/>
<item
android:id="@+id/nav_slideshow"
android:icon="@drawable/ic_menu_slideshow"
android:title="@string/menu_slideshow"
App:showAsAction="always"
android:clickable="true"/>
<item
android:id="@+id/nav_tools"
android:icon="@drawable/ic_menu_manage"
android:title="@string/menu_tools"
android:clickable="true"/>
</group>
<item android:title="Communicate">
<menu>
<item
android:id="@+id/nav_share"
android:icon="@drawable/ic_menu_share"
android:title="@string/menu_share"
android:clickable="true"/>
<item
android:id="@+id/nav_send"
android:icon="@drawable/ic_menu_send"
android:title="@string/menu_send"
android:clickable="true"/>
</menu>
</item>

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/nav_home">
<fragment
android:id="@+id/nav_home"
android:name="com.example.login.ui.home.HomeFragment"
android:label="@string/menu_home"
tools:layout="@layout/fragment_home"
android:clickable="true"/>
<fragment
android:id="@+id/nav_gallery"
android:name="com.example.login.ui.gallery.GalleryFragment"
android:label="@string/menu_gallery"
tools:layout="@layout/fragment_gallery" />
<fragment
android:id="@+id/nav_slideshow"
android:name="com.example.login.ui.slideshow.SlideshowFragment"
android:label="@string/menu_slideshow"
tools:layout="@layout/fragment_slideshow" />
<fragment
android:id="@+id/nav_tools"
android:name="com.example.login.ui.tools.ToolsFragment"
android:label="@string/menu_tools"
tools:layout="@layout/fragment_tools" />
<fragment
android:id="@+id/nav_share"
android:name="com.example.login.ui.share.ShareFragment"
android:label="@string/menu_share"
tools:layout="@layout/fragment_share" />
<fragment
android:id="@+id/nav_send"
android:name="com.example.login.ui.send.SendFragment"
android:label="@string/menu_send"
tools:layout="@layout/fragment_send" />

activity_nav.xml

<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">
<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_nav"
app:menu="@menu/activity_nav_drawer" />
<include
layout="@layout/app_bar_nav"
android:layout_width="match_parent"
android:layout_height="match_parent" />

Answer 1

我已经更新了我的答案，请检查我是否添加了侦听器

public class NavActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{
private AppBarConfiguration mAppBarConfiguration;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nav);
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);
navigationView.setNavigationItemSelectedListener(this);
// 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);
Toolbar myToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(myToolbar);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.nav, 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 onNavigationItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.nav_home: {
Toast.makeText(NavActivity.this, "Anmeldung Fehlgeschlagen", Toast.LENGTH_LONG).show();
return true;
}
case R.id.nav_gallery:
// User chose the "Favorite" action, mark the current item
// as a favorite...
return true;
}
return super.onOptionsItemSelected(item);
}