I am receiving this error after launching the app and then tapping a menu item (most of the menu items result in this error). The menu is also not looking like it did before - it is supposed to be a collapsible menu on the left side of the app, but it takes up the whole screen and isn't collapsible. I have migrated the code to AndroidX, and I'm using Android Studio. I am testing the app on API 28, but this error comes up on 29 and 30 as well. Both in the emulator and on a physical device.
Let me know if I am missing code that I should have added to this post - I am very new to Android Studio. Thank you for any information you can give me. I also followed this code here and it is giving me the same error:
DrawerLayout mDrawerLayout;
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
if (mDrawerLayout.isDrawerOpen(GravityCompat.START)) {
mDrawerLayout.closeDrawer(GravityCompat.START);
}
This is the error log:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.ccgo, PID: 6729
java.lang.ClassCastException: com.google.android.material.navigation.NavigationView cannot be cast to androidx.drawerlayout.widget.DrawerLayout
at com.ccgo.HomeActivity.onNavigationItemSelected(HomeActivity.java:858)
at com.google.android.material.navigation.NavigationView$1.onMenuItemSelected(NavigationView.java:217)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:834)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:985)
at com.google.android.material.internal.NavigationMenuPresenter$1.onClick(NavigationMenuPresenter.java:416)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
I/Process: Sending signal. PID: 6729 SIG: 9
Here's the code for HomeActivity.java:
public boolean onNavigationItemSelected(MenuItem item)
{
// Handle navigation view item clicks here.
switch (item.getItemId())
{
//******************Admin Navigation****************
case R.id.nav_mng_home:
mImgDashboard.setVisibility(View.VISIBLE);
mTxtFragmentName.setVisibility(View.GONE);
setBottomMenuIconAdmin(1);
if(Integer.parseInt(pref.getRoleId())==AppConstant.UserType.ADMIN)
{
setFragment(new FragmentAdminDashboard());
}
else if(Integer.parseInt(pref.getRoleId())==AppConstant.UserType.COACH)
{
setFragment(new FragmentCoachDashboard());
}
else if(Integer.parseInt(pref.getRoleId())==AppConstant.UserType.USER)
{
setFragment(new FragmentUserDashboard());
}
break;
case R.id.nav_mng_challenge:
setFragment(new FragmentManageChallenge());
mImgDashboard.setVisibility(View.GONE);
mTxtFragmentName.setVisibility(View.VISIBLE);
mTxtFragmentName.setText(R.string.mng_challenges);
setBottomMenuIconAdmin(2);
break;
//I removed the cases & some other code for brevity
DrawerLayout drawer = findViewById(R.id.drawer_layout); //This is line 858
drawer.closeDrawer(GravityCompat.START);
return true;
}
Code snippet from NavigationView.java:
this.menu.setCallback(
new MenuBuilder.Callback() {
@Override
public boolean onMenuItemSelected(MenuBuilder menu, MenuItem item) {
return listener != null && listener.onNavigationItemSelected(item); //This is line 217
}
@Override
public void onMenuModeChange(MenuBuilder menu) {}
});
presenter.setId(PRESENTER_NAVIGATION_VIEW_ID);
presenter.initForMenu(context, this.menu);
presenter.setItemIconTintList(itemIconTint);
presenter.setOverScrollMode(getOverScrollMode());
Code from MenuBuilder:
boolean dispatchMenuItemSelected(@NonNull MenuBuilder menu, @NonNull MenuItem item) {
return mCallback != null && mCallback.onMenuItemSelected(menu, item);
}
I have looked at this post and tried the following change but it didn't make a difference.
DrawerLayout drawer = (DrawerLayout)findViewById(R.id.drawer_layout);
I found the solution - I have two 'activity_home.xml' files (one for two different app themes; the other is called 'actiivty_home_red.xml'). When migrating the app to AndroidX, I had a lot of stuff I had to manually switch over. In both of these files, I had com.google.android.material.navigation.NavigationView as the outer tag and the inner tag. I needed to change the outer tag to androidx.drawerlayout.widget.DrawerLayout. I didn't have to change anything in any other files. This site helped guide me in the right direction.
Old code:
<?xml version="1.0" encoding="utf-8"?>
<com.google.android.material.navigation.NavigationView 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="false"
tools:openDrawer="start">
<include
layout="@layout/app_bar_home"
android:layout_width="match_parent"
android:layout_height="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"
android:background="@color/white"
android:fitsSystemWindows="true"
app:theme="@style/ThemeOverlay.AppCompat.navTheme"
app:headerLayout="@layout/nav_header_main_red"
app:menu="@menu/activity_main_drawer" />
</com.google.android.material.navigation.NavigationView>
Updated/working code:
<?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="false"
tools:openDrawer="start">
<include
layout="@layout/app_bar_home"
android:layout_width="match_parent"
android:layout_height="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"
android:background="@color/white"
android:fitsSystemWindows="true"
app:theme="@style/ThemeOverlay.AppCompat.navTheme"
app:headerLayout="@layout/nav_header_main_red"
app:menu="@menu/activity_main_drawer" />
</androidx.drawerlayout.widget.DrawerLayout>