BottomNavigationView na databinding inside viewmodel - android, layout android, mvvm, android-databinding, bottomnavigationview

layout:

<android.support.design.widget.BottomNavigationView
android:id="@+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:onNavigationItemSelected="@{viewModel.onNavigationItemSelected}"
android:background="?android:attr/windowBackground"
app:menu="@menu/menu_home_tab" />

kód:

@BindingAdapter("onNavigationItemSelected")
public static void setOnNavigationItemSelected(
BottomNavigationView view, BottomNavigationView listener) {
view.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {

switch (item.getItemId()) {
case R.id.navigation_dashboard:
Log.d("test","test1");
return true;
case R.id.navigation_notifications:
Log.d("test","test2");
return true;

}
return false;
}

});

}

To vráti chybu

Error:(183, 49) Could not find accessor viewmodel.onNavigationItemSelected

Snažím sa implementovať databinding na mojom bottomnavigationview

odpovede:

Mali by ste mať onNavigationItemSelected() deklarované vo vašom viewModel trieda:

class ViewModel {

@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.navigation_dashboard:
Log.d("test","test1");
return true;
case R.id.navigation_notifications:
Log.d("test","test2");
return true;
}
return false;
}
}

Vo vašom xml použite odkaz na metódu:

app:onNavigationItemSelected="@{viewModel::onNavigationItemSelected}"