SwipeToDeleteCallbac.java

package io.keinix.protoflow.util;

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.support.v4.content.ContextCompat;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.helper.ItemTouchHelper;
import android.view.View;

import io.keinix.protoflow.R;
import io.keinix.protoflow.tasks.TasksAdapter;

public  class SwipeToDeleteCallback extends ItemTouchHelper.SimpleCallback {

    private TasksAdapter mAdapter;

    private Drawable icon;
    private final ColorDrawable background;


    public SwipeToDeleteCallback(MyAdapter adapter) {
        super(0,ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT);
        mAdapter = adapter;
        icon = ContextCompat.getDrawable(mAdapter.getContext(),
                R.drawable.ic_delete_white_36);
        background = new ColorDrawable(Color.RED);
    }

    @Override
    public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
        // used for up and down movements
        return false;
    }

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

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

        View itemView = viewHolder.itemView;
        int backgroundCornerOffset = 20; //so background is behind the rounded corners of itemView

        int iconMargin = (itemView.getHeight() - icon.getIntrinsicHeight()) / 2;
        int iconTop = itemView.getTop() + (itemView.getHeight() - icon.getIntrinsicHeight()) / 2;
        int iconBottom = iconTop + icon.getIntrinsicHeight();

        if (dX > 0) { // Swiping to the right
            int iconLeft = itemView.getLeft() + iconMargin + icon.getIntrinsicWidth();
            int iconRight = itemView.getLeft() + iconMargin;
            icon.setBounds(iconLeft, iconTop, iconRight, iconBottom);

            background.setBounds(itemView.getLeft(), itemView.getTop(),
                    itemView.getLeft() + ((int) dX) + backgroundCornerOffset, itemView.getBottom());
        } else if (dX < 0) { // Swiping to the left
            int iconLeft = itemView.getRight() - iconMargin - icon.getIntrinsicWidth();
            int iconRight = itemView.getRight() - iconMargin;
            icon.setBounds(iconLeft, iconTop, iconRight, iconBottom);

            background.setBounds(itemView.getRight() + ((int) dX) - backgroundCornerOffset,
                    itemView.getTop(), itemView.getRight(), itemView.getBottom());
        } else { // view is unSwiped
            background.setBounds(0, 0, 0, 0);
        }

        background.draw(c);
        icon.draw(c);
    }
}

@araxis +1 ! thank you for sharing

Code leaves the bloody trash can in the middle of the row if the user doesn't complete the swipe!

Hi,
there is a bug on this for left to right swipe

line 55 and 56 should be

int iconLeft = itemView.getLeft() + iconMargin;
int iconRight = itemView.getLeft() + iconMargin + icon.getIntrinsicWidth();

Hi,
there is a bug on this for left to right swipe

line 55 and 56 should be

int iconLeft = itemView.getLeft() + iconMargin;
int iconRight = itemView.getLeft() + iconMargin + icon.getIntrinsicWidth();

Thank you! That saved my day :)

My problem was that the icon not disappeared after the user cancelled the swipe.
This solved my problem:

} else {  // view is unSwiped
      icon.setBounds(0, 0, 0, 0);     // ADD THIS LINE
      background.setBounds(0, 0, 0, 0);
   }

Can you provide a link to the TaskAdapter code and coordinator_layout.xml. Thanks

My problem was that the icon not disappeared after the user cancelled the swipe.
This solved my problem:

} else {  // view is unSwiped
      icon.setBounds(0, 0, 0, 0);     // ADD THIS LINE
      background.setBounds(0, 0, 0, 0);
   }

or you just don't draw it

for me, Icon does not show. icon.draw(c) is not working

@ZaccharieBOUVY you're welcome.

thanks man!