java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.isRecycled()' on a null object reference

Question

I am trying to implement swipe to delete in RecyclerView. Everything seems to be working fine except drawing a delete icon below the item that's being swiped.

This is how I am doing it:

ItemTouchHelper.SimpleCallback simpleItemTouchCallback = new ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {

            @Override
            public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
                return false;
            }

            @Override
            public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {
                int position = viewHolder.getAdapterPosition();

//                Do my stuff
//                }
            }

            @Override
            public void onChildDraw(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {

                Bitmap icon;
                if(actionState == ItemTouchHelper.ACTION_STATE_SWIPE){

                    View itemView = viewHolder.itemView;
                    float height = (float) itemView.getBottom() - (float) itemView.getTop();
                    float width = height / 3;

                    if(dX > 0){
                        p.setColor(Color.parseColor("#388E3C"));
                        RectF background = new RectF((float) itemView.getLeft(), (float) itemView.getTop(), dX,(float) itemView.getBottom());
                        c.drawRect(background,p);
                        icon = BitmapFactory.decodeResource(getActivity().getResources(), R.drawable.ic_delete);
                        RectF icon_dest = new RectF((float) itemView.getLeft() + width ,(float) itemView.getTop() + width,(float) itemView.getLeft()+ 2*width,(float)itemView.getBottom() - width);
                        c.drawBitmap(icon,null,icon_dest,p);
                    } else {
                        p.setColor(Color.parseColor("#D32F2F"));
                        RectF background = new RectF((float) itemView.getRight() + dX, (float) itemView.getTop(),(float) itemView.getRight(), (float) itemView.getBottom());
                        c.drawRect(background,p);
                        icon = BitmapFactory.decodeResource(getActivity().getResources(), R.drawable.ic_delete);
                        RectF icon_dest = new RectF((float) itemView.getRight() - 2*width ,(float) itemView.getTop() + width,(float) itemView.getRight() - width,(float)itemView.getBottom() - width);
                        c.drawBitmap(icon,null,icon_dest,p);
                    }
                }
                super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
            }
        };
        ItemTouchHelper itemTouchHelper = new ItemTouchHelper(simpleItemTouchCallback);
        itemTouchHelper.attachToRecyclerView(mRecyclerView);

It is throwing

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.isRecycled()' on a null object reference

Full StackTrace

09-12 01:28:58.386 26575-26575/com.ozuf.booker E/AndroidRuntime: FATAL EXCEPTION: main
                                                                     Process: com.ozuf.booker, PID: 26575
                                                                     java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.isRecycled()' on a null object reference
                                                                         at android.graphics.Canvas.throwIfCannotDraw(Canvas.java:1281)
                                                                         at android.view.GLES20Canvas.drawBitmap(GLES20Canvas.java:620)
                                                                         at com.ozuf.booker.fragments.BookFragment$1.onChildDraw(BookFragment.java:149)
                                                                         at android.support.v7.widget.helper.ItemTouchHelper$Callback.onDraw(ItemTouchHelper.java:1956)
                                                                         at android.support.v7.widget.helper.ItemTouchHelper$Callback.access$1400(ItemTouchHelper.java:1356)
                                                                         at android.support.v7.widget.helper.ItemTouchHelper.onDraw(ItemTouchHelper.java:542)
                                                                         at android.support.v7.widget.RecyclerView.onDraw(RecyclerView.java:3373)
                                                                         at android.view.View.draw(View.java:15635)
                                                                         at android.support.v7.widget.RecyclerView.draw(RecyclerView.java:3308)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14568)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ViewGroup.recreateChildDisplayList(ViewGroup.java:3588)
                                                                         at android.view.ViewGroup.dispatchGetDisplayList(ViewGroup.java:3567)
                                                                         at android.view.View.updateDisplayListIfDirty(View.java:14528)
                                                                         at android.view.View.getDisplayList(View.java:14590)
                                                                         at android.view.ThreadedRenderer.updateViewTreeDisplayList(ThreadedRenderer.java:273)
                                                                         at android.view.ThreadedRenderer.updateRootDisplayList(ThreadedRenderer.java:279)
                                                                         at android.view.ThreadedRenderer.draw(ThreadedRenderer.java:318)
                                                                         at android.view.ViewRootImpl.draw(ViewRootImpl.java:2575)
                                                                         at android.view.ViewRootImpl.performDraw(ViewRootImpl.java:2385)
                                                                         at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2012)
                                                                         at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1073)
                                                                         at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5988)
                                                                         at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
                                                                        at android.view.Choreographer.doCallbacks(Chor

Line 149 is c.drawBitmap(icon,null,icon_dest,p); I have debugged and I saw that icon is null but I don't understand why it;s null since I've already assigned it a value.

I'm facing the same issue. The accepted answer didn't solve my problem. Any suggestion on how to solve this issue? — Sujit Devkar, Mar 07 '17 at 07:02
For anyone looking for answer here, the problem is caused by the Bitmap conversion and possibly because you are assuming a vector drawable as bitmap. If you are using vector drawable try a different approach than using the same method — shreknit, Apr 01 '20 at 23:39

Marcin Orlowski · Accepted Answer · 2016-09-12T01:05:09.663

20

I don't understand why it;s null since I've already assigned it a value.

Yes. You did => null. The problem is elsewhere. See docs for decodeResource():

Returns: The decoded bitmap, or null if the image could not be decoded.

so you need to a) always check for that condition, b) check why exactly it happens with the data you try to decode.

edited Sep 12 '16 at 01:05

answered Sep 12 '16 at 00:57

Marcin Orlowski

72,056
11
123
141

4

Thanks for the help. I was actually decoding a vector drawable, that was the cause of the nullpointer. I used this solution http://stackoverflow.com/a/24389104/6181476 to create a bitmap out of the vector drawable instead of decoding it. – X09 Sep 12 '16 at 01:15
same problem. decoding vector drawable – Harsh Patel Jun 06 '17 at 05:47

score 17 · Answer 2 · edited Mar 03 '18 at 14:48

17

The error is because of the drawable might be a Vector.

Drawable drawable = ContextCompat.getDrawable(StreamActivity.this,R.drawable.ic_close)
Bitmap icon = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(icon);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);

edited Mar 03 '18 at 14:48

Pawan Singh Chauhan

253
1
10

answered Nov 17 '17 at 11:42

Mayank

181
2
9

score 4 · Answer 3 · answered Sep 20 '18 at 10:15

4

Trying to decode a vector drawable into Bitmap, gives such error. So try to use any image with format .png, .jpeg etc in case of decoding resource to Bitmap.

answered Sep 20 '18 at 10:15

Sarojini2064130

221
3
7

score 1 · Answer 4 · answered Jul 20 '20 at 14:55

1

Answer is check if bitmap is null or reycled() before passing it to ImageView.

if(resource!==null && !resource.isRecycled)
    imageView.setImageBitmap(resource)

answered Jul 20 '20 at 14:55

Hitesh Sahu

41,955
17
205
154

score 0 · Answer 5 · answered May 07 '19 at 00:11

0

My problem was that android added a vector drawable anydpi along with the multiple created image assets for the icon. I deleted the anydpi variant and it all works fine now.

answered May 07 '19 at 00:11

seekingStillness

4,833
5
38
68

score 0 · Answer 6 · edited Nov 08 '20 at 22:57

0

I switched from:

android:layout_width="1095dp"
android:layout_height="1200dp"

To:

android:layout_width="wrap_content"
android:layout_height="wrap_content"

Then the error went away.

Inspired by seekingStillness's answer

edited Nov 08 '20 at 22:57

Amirhossein Yari

2,054
3
26
38

answered Nov 08 '20 at 20:44

Lowell Prange

1

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.isRecycled()' on a null object reference

6 Answers6