notifyItemChanged not refreshing view

Question

First of all, I worked on this all day but could not get anything done. I have a RecyclerView with an adapter that uses RecyclerView's SortedList. I tried implementing TouchHelper with the callback class:

public class TimerListTouchHelperCallback extends ItemTouchHelper.SimpleCallback {

    private OnItemChangeListener onItemChangeListener;

    public TimerListTouchHelperCallback(OnItemChangeListener listener, int dragDirs, int swipeDirs) {
        super(dragDirs, swipeDirs);

        this.onItemChangeListener = listener;

    }

    @Override
    public int getSwipeDirs(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
        TimerHolder holder = (TimerHolder) viewHolder;

        int holderState = holder.getState();

        if (holderState == TimerHolder.TIMER_PENDING_DELETE) return 0;
        else return super.getSwipeDirs(recyclerView, viewHolder);
    }

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




    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int swipeDir) {
        TimerHolder holder = (TimerHolder) viewHolder;

        int position = holder.getAdapterPosition();
        // ViewHolder's state is changed that should handle the layout change.
        holder.setState(TimerHolder.TIMER_PENDING_DELETE); 

        if (onItemChangeListener != null) onItemChangeListener.onItemSwiped(position);
    }


    protected interface OnItemChangeListener{
        void onItemSwiped(int position);
    }
}

Here is the initialization of the TouchHelper

timerAdapter = new TimerAdapter(this, timerList);
    timerListView.setAdapter(timerAdapter);

TimerListTouchHelperCallback touchHelperCallback = new TimerListTouchHelperCallback(
        timerAdapter,
        ItemTouchHelper.LEFT,
        ItemTouchHelper.LEFT);

ItemTouchHelper swipeToDismissTouchHelper = new ItemTouchHelper(touchHelperCallback);

swipeToDismissTouchHelper.attachToRecyclerView(timerListView);

My adapter implements the interface OnItemChangeListener

@Override
public void onItemSwiped(int position) {
    notifyItemChanged(position);
    removalPendingTimers.add(timerList.get(position));
}

My ViewHolder reads the state and when the state is TimerHolder.TIMER_PENDING_DELETE it hides the rest of the view and shows the interface with an undo button. But this is not happening until I scroll the view out and scroll it back again. Any suggestions what I am missing?

Links

Adapter class ViewHolder class

shouldn't you remove the item from your item list when it is swiped and then notify the adapter? — M. Erfan Mowlaei, Aug 18 '16 at 14:53
`OnItemSwiped` will call a handler to remove the item later, just like in gmail app. — Aayush Subedi, Aug 18 '16 at 14:57
if it calls a handler `later` then this is the problem, it notifies adapter before it makes the change. I guess @Dawid van Graan has given the answer or something close to it. — M. Erfan Mowlaei, Aug 18 '16 at 15:02
I do not want the items to be removed at that instant but rather give an option to Undo the deletion. The problem is the layout containing the Undo button is not shown even after calling notifyItemChanged. — Aayush Subedi, Aug 18 '16 at 15:04
I am using support library 23.4.0 com.android.support:appcompat-v7:23.4.0 com.android.support:design:23.4.0 com.android.support:recyclerview-v7:23.4.0 — Aayush Subedi, Aug 18 '16 at 15:12
please give full code of your adapter class and initialization for it so that I can debug it faster. — M. Erfan Mowlaei, Aug 18 '16 at 15:24

score 3 · Answer 1 · answered Aug 18 '16 at 20:05

3

Finally got it running. Since notifyItemChanged was not cutting it (which it should have), I used notifyItemRemoved followed by notifyItemInserted.

Lags just a little bit but works.

answered Aug 18 '16 at 20:05

Aayush Subedi

141
1
12

I'm currently running into the same issue and using `notifyItemRemoved` followed by `notifyItemInserted` seems to work. Oddly `notifyDataSetChanged` also works but not`notifyItemChanged`. It's not an ideal fix but better then refreshing the entire list. – Kris B May 24 '19 at 00:31
on my `dimissListener` i needed to add a `notifyItemChanged` to get work perfectly – Acauã Pitta Apr 15 '20 at 20:58

Dawid van Graan · Answer 2 · 2016-08-19T09:45:15.747

2

I've created a simple example Android App to better understand the question.

It makes use of notifyItemChanged(position); when the user swipes the item left or right to show the undo view. When the undo time expires it calls notifyItemRemoved(position) to remove it from the list. See the GIF for example, does not leave any empty rows.

https://github.com/DawidvanGraan/ExampleRecycleViewSwipeDismiss

edited Aug 19 '16 at 09:45

answered Aug 18 '16 at 14:54

Dawid van Graan

21
2

I was looking at the code all night yesterday, and it seems there is something wrong with my implementation of recyclerview and adapter and not with the TouchHelperClass – Aayush Subedi Aug 19 '16 at 10:24

notifyItemChanged not refreshing view

2 Answers2