底部导航视图无法获取课程

如何解决底部导航视图无法获取课程

我最近将项目迁移到androidx，这给了我一个新的错误 在我迁移到androidx之前，它可以完美地工作 问题出在底部导航视图上 我不明白为什么迁移会导致底部导航无法正常运行，并且以前运行正常 这是我的原木猫

2020-10-23 11:50:36.005 1770-1770/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: umo.com.players,PID: 1770
java.lang.RuntimeException: Unable to start activity ComponentInfo{umo.com.players/umo.com.players.Home.HomeActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.class java.lang.Object.getClass()' on a null object reference
    at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2868)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2958)
    at android.app.ActivityThread.-wrap12(UnkNown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1653)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6739)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:449)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
 Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.class java.lang.Object.getClass()' on a null object reference
    at com.ittianyu.bottomnavigationviewex.BottomNavigationViewEx.getBottomNavigationItemViews(BottomNavigationViewEx.java:474)
    at com.ittianyu.bottomnavigationviewex.BottomNavigationViewEx.enableAnimation(BottomNavigationViewEx.java:246)
    at umo.com.players.Utils.BottomNavigationViewHelper.setupBottomNavigationView(BottomNavigationViewHelper.java:30)
    at umo.com.players.Home.HomeActivity.setupBottomNavigationView(HomeActivity.java:197)
    at umo.com.players.Home.HomeActivity.onCreate(HomeActivity.java:79)
    at android.app.Activity.performCreate(Activity.java:7045)
    at android.app.Activity.performCreate(Activity.java:7036)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1217)
    at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2815)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2958) 
    at android.app.ActivityThread.-wrap12(UnkNown Source:0) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1653) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:164) 
    at android.app.ActivityThread.main(ActivityThread.java:6739) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:449) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) 

这是我的底部导航视图类

public class BottomNavigationViewHelper {

private static final String TAG = "BottomNavigationViewHel";

public static void setupBottomNavigationView(BottomNavigationViewEx bottomNavigationViewEx){
    Log.d(TAG,"setupBottomNavigationView: Setting up BottomNavigationView");
    bottomNavigationViewEx.enableAnimation(false);
    bottomNavigationViewEx.enableItemShiftingMode(false);
    bottomNavigationViewEx.enableShiftingMode(false);
    bottomNavigationViewEx.setTextVisibility(false);
}

public static void enableNavigation(final Context context,final Activity callingActivity,BottomNavigationViewEx view){
    view.setonNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()){

                case R.id.ic_house:
                    Intent intent1 = new Intent(context,HomeActivity.class);//ACTIVITY_NUM = 0
                    context.startActivity(intent1);
                    callingActivity.overridePendingTransition(R.anim.fade_in,R.anim.fade_out);
                    break;

                case R.id.ic_search:
                    Intent intent2  = new Intent(context,SearchActivity.class);//ACTIVITY_NUM = 1
                    context.startActivity(intent2);
                    callingActivity.overridePendingTransition(R.anim.fade_in,R.anim.fade_out);
                    break;

                case R.id.ic_circle:
                    Intent intent3 = new Intent(context,CameraActivity.class);//ACTIVITY_NUM = 2
                    context.startActivity(intent3);
                    callingActivity.overridePendingTransition(R.anim.fade_in,R.anim.fade_out);
                    break;

                case R.id.ic_alert:
                    Intent intent4 = new Intent(context,TournamentActivity.class);//ACTIVITY_NUM = 3
                    context.startActivity(intent4);
                    callingActivity.overridePendingTransition(R.anim.fade_in,R.anim.fade_out);
                    break;

                case R.id.ic_android:
                    Intent intent5 = new Intent(context,ProfileActivity.class);//ACTIVITY_NUM = 4
                    context.startActivity(intent5);
                    callingActivity.overridePendingTransition(R.anim.fade_in,R.anim.fade_out);
                    break;
            }


            return false;
         }
       });
   }
}

这是我的家庭活动

     private void setupBottomNavigationView(){
    Log.d(TAG,"setupBottomNavigationView: setting up BottomNavigationView");
    BottomNavigationViewEx bottomNavigationViewEx = (BottomNavigationViewEx) findViewById(R.id.bottomNavViewBar);
    BottomNavigationViewHelper.setupBottomNavigationView(bottomNavigationViewEx);
    BottomNavigationViewHelper.enableNavigation(mContext,this,bottomNavigationViewEx);
    Menu menu = bottomNavigationViewEx.getMenu();
    MenuItem menuItem = menu.getItem(ACTIVITY_NUM);
    menuItem.setChecked(true);
    }