public static final float ALPHA_FULL = 1.0f;
public void onChildDraw(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {
if (actionState == ItemTouchHelper.ACTION_STATE_SWIPE) {
// Get RecyclerView item from the ViewHolder
View itemView = viewHolder.itemView;
Paint p = new Paint();
Bitmap icon;
if (dX > 0) {
/* Note, ApplicationManager is a helper class I created
myself to get a context outside an Activity class -
feel free to use your own method */
icon = BitmapFactory.decodeResource(
ApplicationManager.getContext().getResources(), R.drawable.myleftdrawable);
/* Set your color for positive displacement */
p.setARGB(255, 255, 0, 0);
// Draw Rect with varying right side, equal to displacement dX
c.drawRect((float) itemView.getLeft(), (float) itemView.getTop(), dX,
(float) itemView.getBottom(), p);
// Set the image icon for Right swipe
c.drawBitmap(icon,
(float) itemView.getLeft() + convertDpToPx(16),
(float) itemView.getTop() + ((float) itemView.getBottom() - (float) itemView.getTop() - icon.getHeight())/2,
p);
} else {
icon = BitmapFactory.decodeResource(
ApplicationManager.getContext().getResources(), R.drawable.myrightdrawable);
/* Set your color for negative displacement */
p.setARGB(255, 0, 255, 0);
// Draw Rect with varying left side, equal to the item's right side
// plus negative displacement dX
c.drawRect((float) itemView.getRight() + dX, (float) itemView.getTop(),
(float) itemView.getRight(), (float) itemView.getBottom(), p);
//Set the image icon for Left swipe
c.drawBitmap(icon,
(float) itemView.getRight() - convertDpToPx(16) - icon.getWidth(),
(float) itemView.getTop() + ((float) itemView.getBottom() - (float) itemView.getTop() - icon.getHeight())/2,
p);
}
// Fade out the view as it is swiped out of the parent's bounds
final float alpha = ALPHA_FULL - Math.abs(dX) / (float) viewHolder.itemView.getWidth();
viewHolder.itemView.setAlpha(alpha);
viewHolder.itemView.setTranslationX(dX);
} else {
super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
}
}
private int convertDpToPx(int dp){
return Math.round(dp * (getResources().getDisplayMetrics().xdpi / DisplayMetrics.DENSITY_DEFAULT));
}