问题
I'm fairly new to android dev. I'm checking the material design library and I've implemented a navigation drawer with a bottom navigation to navigate easily through fragments. Both components work just fine but I don't how to coordinate the navigation with both components. For example when a fragment is toggled on the navigation drawer it changed the layout but the button navigation selected item is not changed with it.
How can I solve this issue and link both components to work with each other and sync the changed selected item?
This is what my java file looks like and here's link for the whole project on GitHub: https://github.com/mreek/NavigationDrawer
Thank you in advance.
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
private DrawerLayout drawer;
private TextView appBarTV;
private static final String TAG = "MyActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent intent= new Intent(this,IntroActivity.class);
startActivity(intent);
drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
appBarTV = findViewById(R.id.appbar_text_view);
ImageButton menuRight = findViewById(R.id.leftRight);
menuRight.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
drawer.openDrawer(GravityCompat.START);
}
}
});
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
BottomNavigationView bottomNavigationView = (BottomNavigationView)findViewById(R.id.navigation);
bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
Fragment selectedFragment = null;
switch (item.getItemId()) {
case R.id.action_item1:
selectedFragment = MainFragment.newInstance();
break;
case R.id.action_item2:
selectedFragment = AccountFragment.newInstance();
break;
case R.id.action_item3:
selectedFragment = SellFragment.newInstance();
break;
case R.id.action_item4:
selectedFragment = ChatFragment.newInstance();
break;
case R.id.action_item5:
selectedFragment = NotificationFragment.newInstance();
break;
}
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.f_container, selectedFragment);
transaction.commit();
return true;
}
});
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.f_container, MainFragment.newInstance());
transaction.commit();
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public boolean onNavigationItemSelected(MenuItem item) {
drawer.closeDrawers();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
int id = item.getItemId();
if (id == R.id.nav_camera) {
MainFragment fragment = new MainFragment();
ft.replace(R.id.f_container, fragment);
ft.commit();
} else if (id == R.id.nav_gallery) {
//appBarTV.setText("Fragment With Tabs");
ChatFragment fragment = new ChatFragment();
ft.replace(R.id.f_container, fragment);
ft.commit();
} else if (id == R.id.nav_slideshow) {
AccountFragment fragmentTab = new AccountFragment();
ft.replace(R.id.f_container, fragmentTab);
ft.commit();
} else if (id == R.id.nav_share) {
Toast.makeText(this, "Partager", Toast.LENGTH_SHORT).show();
} else if (id == R.id.nav_send) {
Toast.makeText(this, "Rate 5 stars", Toast.LENGTH_SHORT).show();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
}
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.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">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include layout="@layout/app_bar_main" />
<FrameLayout
android:id="@+id/f_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<android.support.design.widget.BottomNavigationView
android:id="@+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginBottom="3dp"
android:background="@color/white"
app:itemIconTint="@color/blue"
app:itemTextColor="@color/blue"
app:menu="@menu/bottom_navigation_items" />
</RelativeLayout>
<android.support.design.widget.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"
app:itemTextColor="@color/black"/>
</android.support.v4.widget.DrawerLayout>
回答1:
try this code:
private void setupNavDrawer(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
Fragment fragment = null;
switch (item.getItemId()){
case R.id.nav_gallery:
fragment = new GalleryFragment();
break;
case R.id.nav_share:
fragment = new ShareFragment();
break;
default:
fragment = new GalleryFragment();
break;
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
//if checked - set title menu
item.setChecked(true);
setTitle(item.getTitle());
mDrawerLayout.closeDrawers();
return true;
}
});
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
............//nav
setupNavDrawer(navigationView);
}
回答2:
First of all you should avoid recreating fragments when user selected a tab from bottom navigation. You should keep your fragments as private variables:
private DrawerLayout drawer;
private BottomNavigationView bottomNavigationView;
private MainFragment mainFragment = MainFragment.newInstance();
private AccountFragment accountFragment = AccountFragment.newInstance();
private SellFragment sellFragment = SellFragment.newInstance();
private ChatFragment chatFragment = ChatFragment.newInstance();
private NotificationFragment notificationFragment = NotificationFragment.newInstance();
When user selects a tab just swich to that fragment:
bottomNavigationView.setOnNavigationItemSelectedListener(item -> {
Fragment selectedFragment = null;
switch (item.getItemId()) {
case R.id.action_announces:
selectedFragment = mainFragment;
break;
case R.id.action_account:
selectedFragment = accountFragment;
break;
case R.id.action_sell:
selectedFragment = sellFragment;
break;
case R.id.action_chat:
selectedFragment = chatFragment;
break;
case R.id.action_notifications:
selectedFragment = notificationFragment;
break;
}
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
if (selectedFragment != null) {
transaction.replace(R.id.f_container, selectedFragment);
transaction.commit();
}
return true;
});
When user selects a tab using navigation menu swich to required fragment:
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
drawer.closeDrawers();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
switch (item.getItemId()) {
case R.id.nav_announces:
bottomNavigationView.setSelectedItemId(R.id.action_announces);
ft.replace(R.id.f_container, mainFragment);
break;
case R.id.nav_account:
bottomNavigationView.setSelectedItemId(R.id.action_account);
ft.replace(R.id.f_container, accountFragment);
break;
case R.id.nav_sell:
bottomNavigationView.setSelectedItemId(R.id.action_sell);
ft.replace(R.id.f_container, sellFragment);
break;
case R.id.nav_chat:
bottomNavigationView.setSelectedItemId(R.id.action_chat);
ft.replace(R.id.f_container, chatFragment);
break;
case R.id.nav_notifications:
bottomNavigationView.setSelectedItemId(R.id.action_notifications);
ft.replace(R.id.f_container, notificationFragment);
break;
}
ft.commit();
return true;
}
I have forked your repo and migrated it to AndroidX before fixing it on a new branch called androidx. I made a pull request to you. You can accept and try it.
来源：https://stackoverflow.com/questions/55667686/how-to-coordinate-a-navigation-drawer-with-a-buttom-navigation-view