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Adding a colored background with text/icon under swiped row when using Android's RecyclerView

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遥遥无期
遥遥无期 2020-12-02 07:37

EDIT: The real problem was that my LinearLayout was wrapped in another layout, which caused the incorrect behavior. The accepted answer by Sanvywell has

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  • 春和景丽
    春和景丽 (楼主)
    2020-12-02 08:05

    Here's how I do it without 3rd party library.

    The foreground view will be always visible in the recycler view, and when swipe is performed the background will be visible staying in a static position.

    Create your custom RecyclerView item and add your custom icon, text and background color to the background layout of item. Notice that I put an id to RelativeLayout with id=foreground and id=background.

    Here's mine recylerview_item.xml.

    and from your ViewHolder define your RelativeLayout foreground and background view and make it public. Also create a method that will remove the item. In my case my ViewHolder is under my RecyclerViewAdapter.class, so...

    public class RecyclerViewAdapter extends RecyclerView.Adapter {

    List listItem;

    public RecyclerViewAdapter(...) {
        ...
    } 

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = mInflater.inflate(R.layout.recyclerview_item, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, int position) {
        ....
    }

    @Override
    public int getItemCount() {
        ...
    }

    public class ViewHolder extends RecyclerView.ViewHolder{

        public RelativeLayout foreground, background;

        public ViewHolder(View itemView) {
            super(itemView);

            /** define your foreground and background **/

            foreground = itemView.findViewById(R.id.foreground);
            background = itemView.findViewById(R.id.background);

        }

    }

    /**Call this later to remove the item on swipe**/
    public void removeItem(int position){
        //remove the item here
        listItem.remove(position);
        notifyItemRemoved(position);
    }
}



    And create a class and name it RecyclerItemTouchHelper.class, this is where swipe thing will happen.
    


    public class RecyclerItemTouchHelper extends ItemTouchHelper.SimpleCallback {

    private RecyclerItemTouchHelperListener listener;

    public RecyclerItemTouchHelper(int dragDirs, int swipeDirs, RecyclerItemTouchHelperListener listener) {
        super(dragDirs, swipeDirs);
        this.listener = listener;
    }

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

    @Override
    public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) {
        if (viewHolder != null) {
            final View foregroundView = ((RecyclerViewAdapter.ViewHolder) viewHolder).foreground;
            getDefaultUIUtil().onSelected(foregroundView);
        }
    }

    @Override
    public void onChildDrawOver(Canvas c, RecyclerView recyclerView,
                                RecyclerView.ViewHolder viewHolder, float dX, float dY,
                                int actionState, boolean isCurrentlyActive) {
        final View foregroundView = ((RecyclerViewAdapter.ViewHolder) viewHolder).foreground;
        getDefaultUIUtil().onDrawOver(c, recyclerView, foregroundView, dX, dY,
                actionState, isCurrentlyActive);
    }

    @Override
    public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
        final View foregroundView = ((RecyclerViewAdapter.ViewHolder) viewHolder).foreground;
        getDefaultUIUtil().clearView(foregroundView);
    }

    @Override
    public void onChildDraw(Canvas c, RecyclerView recyclerView,
                            RecyclerView.ViewHolder viewHolder, float dX, float dY,
                            int actionState, boolean isCurrentlyActive) {
        final View foregroundView = ((RecyclerViewAdapter.ViewHolder) viewHolder).foreground;

        getDefaultUIUtil().onDraw(c, recyclerView, foregroundView, dX, dY,
                actionState, isCurrentlyActive);
    }

    @Override
    public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
        listener.onSwiped(viewHolder, direction, viewHolder.getAdapterPosition());
    }

    @Override
    public int convertToAbsoluteDirection(int flags, int layoutDirection) {
        return super.convertToAbsoluteDirection(flags, layoutDirection);
    }

    public interface RecyclerItemTouchHelperListener {
        void onSwiped(RecyclerView.ViewHolder viewHolder, int direction, int position);
    }
}

    


    Now, from your MainActivity.class or wherever your RecyclerView is, attach the RecyclerItemTouchHelper into it. In my case the RecyclerView is in MainActivity.class so I implemented RecyclerItemTouchHelper.RecyclerItemTouchHelperListener into it and override the method onSwiped()...
    


    public class MainActivity extends AppCompatActivity implements RecyclerItemTouchHelper.RecyclerItemTouchHelperListener {

    RecyclerView recyclerView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        //Configure RecyclerView

        recyclerView = (RecyclerView) findViewById(R.id.recyclerView);  
        RecyclerView.LayoutManager mLyoutManager = new LinearLayoutManager(getApplicationContext());
        recyclerView.setLayoutManager(mLyoutManager);
        recyclerView.setItemAnimator(new DefaultItemAnimator());
        adapter = new RecyclerViewAdapter(this);
        adapter.setClickListener(this);
        recyclerView.setAdapter(adapter);
        recyclerView.addItemDecoration(new DividerItemDecoration(recyclerView.getContext(), DividerItemDecoration.VERTICAL));

        //Attached the ItemTouchHelper
        ItemTouchHelper.SimpleCallback itemTouchHelperCallback = new RecyclerItemTouchHelper(0, ItemTouchHelper.LEFT, this);
        new ItemTouchHelper(itemTouchHelperCallback).attachToRecyclerView(recyclerView);
    }

    //define the method onSwiped()
    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction, int position) {
        if (viewHolder instanceof RecyclerViewAdapter.ViewHolder) {
            adapter.removeItem(viewHolder.getAdapterPosition()); //remove the item from the adapter
        }
    }

}

    


    For more information and clarification here is the blog for it.
    
    
    
             
    
                                                        
    
            
            
    
              
                
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