App аварии после щелчка на ImageView что setImageDrawable

Question

мое приложение аварии, когда:

1. HomeActivity начал
2. Перейдите CategoryActivity или Открыть DialogFragment, которые разделяют один и тот же recyclerview viewholder
3. вернуться обратно HomeActivity, нажмите на ImageView, которые имеют setDrawable
4. App аварии

Настоящим является код аварии

10-31 07:45:52.811 25005-25005/com.studio.douka E/AndroidRuntime: FATAL EXCEPTION: main 
      Process: com.studio.douka, PID: 25005 
      java.lang.NullPointerException 
       at 
    android.support.v4.content.ContextCompat.getDrawable(ContextCompat.java:374) 
       at com.studio.douka.PostHolder.setLikeStatus(PostHolder.java:163) 
       at 
    com.studio.douka.PostDialogFragment$3.onDataChange(PostDialogFragment.java:110) 
       at com.google.android.gms.internal.zzaie.zza(Unknown Source) 
       at com.google.android.gms.internal.zzaje.zzcta(Unknown Source) 
       at com.google.android.gms.internal.zzajh$1.run(Unknown Source) 
       at android.os.Handler.handleCallback(Handler.java:733) 
       at android.os.Handler.dispatchMessage(Handler.java:95) 
       at android.os.Looper.loop(Looper.java:136) 
       at android.app.ActivityThread.main(ActivityThread.java:5001) 
       at java.lang.reflect.Method.invokeNative(Native Method) 
       at java.lang.reflect.Method.invoke(Method.java:515) 
       at 
    com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785) 
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601) 
       at dalvik.system.NativeStart.main(Native Method) 

Настоящим является коды, которые делают приложение аварии

PostHolder.java

public class PostHolder extends RecyclerView.ViewHolder { 

    private static final String TAG = PostHolder.class.getSimpleName(); 
    public TextView postTitle; 
    public ImageView postImage; 
    public TextView postLike; 
    public TextView postComment; 
    public ImageView gifImage; 
    public ImageView BtnPostMenu; 
    private static final int POST_TEXT_MAX_LINES = 6; 
    public ValueEventListener mLikeListener; 
    public ValueEventListener mCommentListener; 
    public DatabaseReference mPostRef; 
    public ValueEventListener mPostListener; 
    private final ImageView mLikeIcon; 
    private PostClickListener mListener; 

    public enum LikeStatus {LIKED, NOT_LIKED} 

    private String authorUID; 
    private String photoURL; 
    private String postKey; 
    private String currentStorageRef; 
    private String postText; 

    public PostHolder(View itemView) { 
     super(itemView); 
     postTitle = (TextView) itemView.findViewById(R.id.item_title); 
     postImage = (ImageView) itemView.findViewById(R.id.item_icon); 
     postLike = (TextView) itemView.findViewById(R.id.item_like); 
     postComment = (TextView) itemView.findViewById(R.id.item_comment); 
     mLikeIcon = (ImageView) itemView.findViewById(R.id.post_like_icon); 
     BtnPostMenu = (ImageView) itemView.findViewById(R.id.post_menu_button); 
     gifImage = (ImageView) itemView.findViewById(R.id.gif_image); 

     itemView.findViewById(R.id.post_comment_icon).setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       mListener.showComments(); 
      } 
     }); 

     mLikeIcon.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       mListener.toggleLike(); 
      } 
     }); 

     BtnPostMenu.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       showPopup(v); 
      } 
     }); 

    } 

    public void setPhoto(String url, int width, int height, String isAnimated) { 


     GlideUtil.loadImage(url, postImage, width, height, isAnimated, gifImage); 
    } 

    public void getAuthor(String author) { 

     if (author != null) { 
      authorUID = author; 
     } 
    } 

    public void getStorageRef(String storageRef) { 

     if (storageRef != null) { 
      currentStorageRef = storageRef; 
     } 
    } 

    public void getPhotoURL(String picURL) { 

     if (picURL != null) { 
      photoURL = picURL; 
     } 
    } 

    public void getKey(String key) { 

     if (key != null) { 
      postKey = key; 
     } 
    } 

    public void getText(String pText) { 

     if (pText != null) { 
      postText = pText; 
     } 
    } 

    public void setText(final String text) { 
     if (text == null || text.isEmpty()) { 
      postTitle.setVisibility(View.GONE); 
      return; 
     } else { 
      postTitle.setVisibility(View.VISIBLE); 
      postTitle.setText(text); 
      postTitle.setMaxLines(POST_TEXT_MAX_LINES); 
      postTitle.setOnClickListener(new View.OnClickListener() { 
       @Override 
       public void onClick(View view) { 
        if (postTitle.length() == POST_TEXT_MAX_LINES) { 
         postTitle.setMaxLines(Integer.MAX_VALUE); 
        } else { 
         postTitle.setMaxLines(POST_TEXT_MAX_LINES); 
        } 
       } 
      }); 
     } 
    } 

    public void setNumLikes(long numLikes) { 
     String suffix = numLikes == 1 ? " like" : " likes"; 
     postLike.setText(numLikes + suffix); 
    } 

    public void setNumComments(long numComments) { 
     String suffix = numComments == 1 ? " comment" : " comments"; 
     postComment.setText(numComments + suffix); 
    } 

    public void setLikeStatus(LikeStatus status, Context context) { 
     mLikeIcon.setImageDrawable(ContextCompat.getDrawable(context, 
       status == LikeStatus.LIKED ? R.drawable.heart_full : R.drawable.heart_empty)); 
    } 

    public void setPostClickListener(PostClickListener listener) { 
     mListener = listener; 
    } 

    public interface PostClickListener { 
     void showComments(); 

     void toggleLike(); 
    } 

    public void showPopup(final View v) { 

     final String currentUID = FirebaseUtil.getCurrentUserId(); 

     if (authorUID.equals(currentUID)) { 

      PopupMenu popup = new PopupMenu(v.getContext(), v); 
      MenuInflater inflater = popup.getMenuInflater(); 
      inflater.inflate(R.menu.own_post_menu_popup, popup.getMenu()); 

      popup.getMenu().findItem(R.id.action_edit).setOnMenuItemClickListener(new MenuItem.OnMenuItemClickListener() { 
       @Override 
       public boolean onMenuItemClick(MenuItem item) { 
        showChangeLangDialog(v); 
        return false; 
       } 
      }); 

      popup.getMenu().findItem(R.id.action_delete).setOnMenuItemClickListener(new MenuItem.OnMenuItemClickListener() { 
       @Override 
       public boolean onMenuItemClick(MenuItem item) { 

        FirebaseStorage storage = FirebaseStorage.getInstance(); 
        StorageReference storageRef = storage.getReferenceFromUrl(photoURL); 

        storageRef.delete().addOnSuccessListener(new OnSuccessListener() { 
         @Override 
         public void onSuccess(Object o) { 
          Map<String, Object> childUpdates = new HashMap<>(); 

          childUpdates.put("posts/" + postKey, null); 
          childUpdates.put("comments/" + postKey, null); 
          childUpdates.put("likes/" + postKey, null); 
          childUpdates.put("userNotifications/" + currentUID + "/" + postKey, null); 
          childUpdates.put("people/" + currentUID + "/" + "posts/" + postKey, null); 
          childUpdates.put("postCategory/car/" + postKey, null); 
          childUpdates.put("postCategory/funny/" + postKey, null); 
          childUpdates.put("postCategory/gaming/" + postKey, null); 
          childUpdates.put("postCategory/girl/" + postKey, null); 

          FirebaseUtil.getBaseRef().updateChildren(childUpdates); 
         } 
        }).addOnFailureListener(new OnFailureListener() { 
         @Override 
         public void onFailure(@NonNull Exception exception) { 
          // Uh-oh, an error occurred! 
         } 
        }); 

        return false; 
       } 
      }); 

      popup.show(); 

     } else { 

      PopupMenu popup = new PopupMenu(v.getContext(), v); 
      MenuInflater inflater = popup.getMenuInflater(); 
      inflater.inflate(R.menu.post_menu_popup, popup.getMenu()); 

      popup.getMenu().findItem(R.id.action_report).setOnMenuItemClickListener(new MenuItem.OnMenuItemClickListener() { 
       @Override 
       public boolean onMenuItemClick(MenuItem item) { 
        Toast.makeText(v.getContext(), "Reported,,,", Toast.LENGTH_SHORT).show(); 
        return false; 
       } 
      }); 

      popup.show(); 
     } 
    } 

    public void showChangeLangDialog(View v) { 
     AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(v.getContext()); 
     LayoutInflater inflater = (LayoutInflater) v.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);; 
     final View dialogView = inflater.inflate(R.layout.custom_dialog, null); 
     dialogBuilder.setView(dialogView); 

     final EditText edt = (EditText) dialogView.findViewById(R.id.edit1); 
     edt.setText(postText); 

     dialogBuilder.setTitle("Custom dialog"); 
     dialogBuilder.setMessage("Enter text below"); 
     dialogBuilder.setPositiveButton("Done", new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface dialog, int whichButton) { 
       //do something with edt.getText().toString(); 

       Map<String, Object> childUpdates = new HashMap<>(); 

       childUpdates.put("text", edt.getText().toString()); 

       FirebaseUtil.getPostsRef().child(postKey).updateChildren(childUpdates); 
      } 
     }); 
     dialogBuilder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface dialog, int whichButton) { 
       //pass 
      } 
     }); 
     AlertDialog b = dialogBuilder.create(); 
     b.show(); 
    } 

} 

PostDialogFragment.java

public class PostDialogFragment extends DialogFragment { 
    private static final String TAG = MainActivity.class.getSimpleName(); 

    private String postID = null; 
    private OnPostSelectedListener mListener; 
    private RecyclerView mRecyclerView; 
    private RecyclerView.Adapter<PostHolder> mAdapter; 

    public PostDialogFragment() { 
     // Required empty public constructor 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
     View rootView = inflater.inflate(R.layout.fragment_post_dialog, container, false); 
     getDialog().setTitle("Post"); 

     postID = getArguments().getString("postID"); 

     mRecyclerView = (RecyclerView) rootView.findViewById(R.id.postRecyclerView); 

     return rootView; 
    } 

    @Override 
    public void onActivityCreated(Bundle savedInstanceState) { 
     super.onActivityCreated(savedInstanceState); 

     LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity()); 
     linearLayoutManager.setReverseLayout(true); 
     linearLayoutManager.setStackFromEnd(true); 
     mRecyclerView.setLayoutManager(linearLayoutManager); 

     final List<String> postPaths = new ArrayList<>(); 
     postPaths.add(postID); 

     mAdapter = new FirebasePostQueryAdapter(postPaths, 
       new FirebasePostQueryAdapter.OnSetupViewListener() { 
        @Override 
        public void onSetupView(PostHolder holder, Post post, int position, String postKey) { 
         setupPost(holder, post, position, postKey); 
        } 
       }); 
     mRecyclerView.setAdapter(mAdapter); 
    } 

    private void setupPost(final PostHolder postViewHolder, final Post post, final int position, final String inPostKey) { 
     postViewHolder.setPhoto(post.getFull_url(), post.getImageWidth(), post.getImageHeight(), post.getIsAnimated()); 
     postViewHolder.setText(post.getText()); 
     postViewHolder.getAuthor(post.getAuthor().getUid()); 
     postViewHolder.getPhotoURL(post.getFull_url()); 
     postViewHolder.getStorageRef(getString(R.string.google_storage_bucket)); 
     postViewHolder.getText(post.getText()); 

     final String postKey; 
     if (mAdapter instanceof FirebaseRecyclerAdapter) { 
      postKey = ((FirebaseRecyclerAdapter) mAdapter).getRef(position).getKey(); 
      postViewHolder.getKey(((FirebaseRecyclerAdapter) mAdapter).getRef(position).getKey()); 
     } else { 
      postKey = inPostKey; 
     } 

     ValueEventListener likeListener = new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       postViewHolder.setNumLikes(dataSnapshot.getChildrenCount()); 
       if (dataSnapshot.hasChild(FirebaseUtil.getCurrentUserId())) { 
        postViewHolder.setLikeStatus(PostHolder.LikeStatus.LIKED, getActivity()); 
       } else { 
        postViewHolder.setLikeStatus(PostHolder.LikeStatus.NOT_LIKED, getActivity()); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 

      } 
     }; 
     FirebaseUtil.getLikesRef().child(postKey).addValueEventListener(likeListener); 
     postViewHolder.mLikeListener = likeListener; 

     ValueEventListener commentListener = new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       postViewHolder.setNumComments(dataSnapshot.getChildrenCount()); 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 

      } 
     }; 
     FirebaseUtil.getCommentsRef().child(postKey).addValueEventListener(commentListener); 
     postViewHolder.mCommentListener = commentListener; 

     postViewHolder.setPostClickListener(new PostHolder.PostClickListener() { 
      @Override 
      public void showComments() { 
       Log.d(TAG, "Comment position: " + position); 
       mListener.onPostComment(postKey); 
      } 

      @Override 
      public void toggleLike() { 
       Log.d(TAG, "Like position: " + position); 
       mListener.onPostLike(postKey); 
      } 
     }); 
    } 

    public interface OnPostSelectedListener { 
     void onPostComment(String postKey); 

     void onPostLike(String postKey); 
    } 

    @Override 
    public void onAttach(Context context) { 
     super.onAttach(context); 
     if (context instanceof OnPostSelectedListener) { 
      mListener = (OnPostSelectedListener) context; 
     } else { 
      throw new RuntimeException(context.toString() 
        + " must implement OnPostSelectedListener"); 
     } 
    } 

    @Override 
    public void onDetach() { 
     super.onDetach(); 
     mListener = null; 
    } 

} 

HomeActivity.java

public class HomeActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener, PostFragment.OnPostSelectedListener, PostDialogFragment.OnPostSelectedListener, UploadMethodDialogFragment.OnImageSelectedListener { 

    private AlertDialog userDialog; 
    private ViewPager viewPager; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_home); 

     viewPager = (ViewPager) findViewById(R.id.viewPager); 
     Toolbar toolbar = (Toolbar) findViewById(R.id.toolBar); 
     setSupportActionBar(toolbar); 


     FeedsPagerAdapter adapter = new FeedsPagerAdapter(getSupportFragmentManager()); 
     adapter.addFragment(PostFragment.newInstance(PostFragment.TYPE_NEW), "NEW"); 
     adapter.addFragment(PostFragment.newInstance(PostFragment.TYPE_CATEGORY), "CATEGORY"); 
     adapter.addFragment(PostFragment.newInstance(PostFragment.TYPE_NOTIFICATION), "NOTIFICATIONS"); 
     viewPager.setAdapter(adapter); 
     viewPager.setCurrentItem(0); 
     TabLayout tabLayout = (TabLayout) findViewById(R.id.tabLayout); 
     tabLayout.setupWithViewPager(viewPager); 

     tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() { 
      @Override 
      public void onTabSelected(TabLayout.Tab tab) { 
       viewPager.setCurrentItem(tab.getPosition()); 
      } 

      @Override 
      public void onTabUnselected(TabLayout.Tab tab) { 

      } 

      @Override 
      public void onTabReselected(TabLayout.Tab tab) { 

      } 
     }); 

     DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
     ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
       this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close); 
     drawer.setDrawerListener(toggle); 
     toggle.syncState(); 

     NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view); 
     navigationView.setNavigationItemSelectedListener(this); 
     View header = navigationView.getHeaderView(0); 
     TextView navName = (TextView) header.findViewById(R.id.nav_header_name); 
     TextView navEmail = (TextView) header.findViewById(R.id.nav_header_email); 
     ImageView navProfilePicture = (ImageView) header.findViewById(R.id.nav_profile_picture); 

     FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser(); 
     if (user != null) { 
      // Name, email address, and profile photo Url 
      String user_name = user.getDisplayName(); 
      String user_email = user.getEmail(); 
      Uri pictureURL = user.getPhotoUrl(); 

      navName.setText("" + user_name); 
      navEmail.setText("" + user_email); 
      Glide 
        .with(getApplicationContext()) 
        .load(pictureURL) 
        .into(navProfilePicture); 
     } 


    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.menu_main, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 

     int id = item.getItemId(); 

     return super.onOptionsItemSelected(item); 
    } 

    @SuppressWarnings("StatementWithEmptyBody") 
    @Override 
    public boolean onNavigationItemSelected(MenuItem item) { 
     // Handle navigation view item clicks here. 
     int id = item.getItemId(); 

     if (id == R.id.nav_camera) { 
      // Handle the camera action 
      viewPager.setCurrentItem(0); 

     } else if (id == R.id.nav_gallery) { 
      viewPager.setCurrentItem(1); 

     } else if (id == R.id.nav_slideshow) { 

     } else if (id == R.id.nav_manage) { 

     } else if (id == R.id.nav_share) { 

     } else if (id == R.id.nav_send) { 

     } 

     DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
     drawer.closeDrawer(GravityCompat.START); 
     return true; 
    } 

    class FeedsPagerAdapter extends FragmentPagerAdapter { 
     private final List<Fragment> mFragmentList = new ArrayList<>(); 
     private final List<String> mFragmentTitleList = new ArrayList<>(); 

     public FeedsPagerAdapter(android.support.v4.app.FragmentManager manager) { 
      super(manager); 
     } 

     @Override 
     public Fragment getItem(int position) { 
      return mFragmentList.get(position); 
     } 

     @Override 
     public int getCount() { 
      return mFragmentList.size(); 
     } 

     public void addFragment(Fragment fragment, String title) { 
      mFragmentList.add(fragment); 
      mFragmentTitleList.add(title); 
     } 

     @Override 
     public CharSequence getPageTitle(int position) { 
      return mFragmentTitleList.get(position); 
     } 
    } 

    @Override 
    public void onPostComment(String postKey) { 

     if (postKey == null) { 
      showAlertDialog("无法连接", 
        "Key : " + postKey, false); 
     } else { 
      android.support.v4.app.FragmentManager fm = getSupportFragmentManager(); 
      CommentFragment um = new CommentFragment(); 

      Bundle args = new Bundle(); 
      args.putString("postKey", postKey); 
      um.setArguments(args); 
      um.show(fm, "Comment"); 
     } 

    } 

    @Override 
    public void onPostLike(final String postKey) { 
     final String userKey = FirebaseUtil.getCurrentUserId(); 
     final DatabaseReference postLikesRef = FirebaseUtil.getLikesRef(); 
     postLikesRef.child(postKey).child(userKey).addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       if (dataSnapshot.exists()) { 
        // User already liked this post, so we toggle like off. 
        postLikesRef.child(postKey).child(userKey).removeValue(); 
       } else { 
        postLikesRef.child(postKey).child(userKey).setValue(ServerValue.TIMESTAMP); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError firebaseError) { 

      } 
     }); 
    } 

    @Override 
    public void onUpdateNotification(final String postKey) { 
     final String userKey = FirebaseUtil.getCurrentUserId(); 
     final DatabaseReference notificationRef = FirebaseUtil.getUserNotificationsRef(); 
     notificationRef.child(userKey).child(postKey).addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       if (dataSnapshot.exists()) { 
        HashMap<String, Object> result = new HashMap<>(); 
        result.put("status", false); 
        result.put("count", 0L); 
        notificationRef.child(userKey).child(postKey).updateChildren(result); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError firebaseError) { 

      } 
     }); 
    } 

    @Override 
    public void onPostOpenDialog(final String postKey) { 
     Bundle bundle = new Bundle(); 
     bundle.putString("postID", postKey); 
     //set Fragment class Arguments 
     PostDialogFragment fragObj = new PostDialogFragment(); 
     fragObj.setArguments(bundle); 
     android.support.v4.app.FragmentManager fm = getSupportFragmentManager(); 
     fragObj.show(fm, "Post Fragment"); 
    } 

    public void onPicSelected(String filePath) { 
     if(filePath!=null){ 
      Bundle bundle = new Bundle(); 
      bundle.putString("filePath", filePath); 
      //set Fragment class Arguments 
      UploadPictureDialogFragment fragObj = new UploadPictureDialogFragment(); 
      fragObj.setArguments(bundle); 
      android.support.v4.app.FragmentManager fm = getSupportFragmentManager(); 
      fragObj.show(fm, "上载图片"); 
     } 
    } 

    public void userDetails(MenuItem item) { 

     // [START subscribe_topics] 
     FirebaseMessaging.getInstance().subscribeToTopic("6biC3YfNUiWpHqmasa4O74KPWwC2"); 
     // [END subscribe_topics] 

     // Log and toast 
     String msg = "Subscribed to news topic"; 
     Log.d("Subscribe", msg); 
     Toast.makeText(HomeActivity.this, msg, Toast.LENGTH_SHORT).show(); 

    } 

    public void upload_method(MenuItem item) { 
     android.support.v4.app.FragmentManager fm = getSupportFragmentManager(); 
     UploadMethodDialogFragment um = new UploadMethodDialogFragment(); 
     um.show(fm, "Upload Method"); 
    } 

    private void showAlertDialog(String title, String body, Boolean status) { 
     final AlertDialog.Builder builder = new AlertDialog.Builder(this); 

     builder.setTitle(title).setMessage(body).setNeutralButton("好的", new DialogInterface.OnClickListener() { 
      @Override 
      public void onClick(DialogInterface dialog, int which) { 
       try { 
        userDialog.dismiss(); 
       } catch (Exception e) { 
        // 
       } 
      } 
     }); 
     userDialog = builder.create(); 
     userDialog.show(); 
    } 

    @Override 
    public void onBackPressed() { 
     viewPager.setCurrentItem(0); 
    } 
} 

Я загрузил GIF изображение, а также для лучшего понимания

Answer 1

context предоставляется getDrawable() равна нулю. Это означает, что getActivity() возвращает null, что возможно. Чтобы избежать этого, сохраните контекст активности в onAttach() методе фрагмента и используйте его впоследствии.