I\'m using the RecyclerView like below:
Unfortunately using focusable views to simulate item selection is not a good solution because:
notifyDataSetChanged is calledI wrote a base adapter class to automatically handle item selection with a RecyclerView. Just derive your adapter from it and use drawable state lists with state_selected, like you would do with a list view.
I have a Blog Post Here about it, but here is the code:
public abstract class TrackSelectionAdapter<VH extends TrackSelectionAdapter.ViewHolder> extends RecyclerView.Adapter<VH> {
// Start with first item selected
private int focusedItem = 0;
@Override
public void onAttachedToRecyclerView(final RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
// Handle key up and key down and attempt to move selection
recyclerView.setOnKeyListener(new View.OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
RecyclerView.LayoutManager lm = recyclerView.getLayoutManager();
// Return false if scrolled to the bounds and allow focus to move off the list
if (event.getAction() == KeyEvent.ACTION_DOWN) {
if (keyCode == KeyEvent.KEYCODE_DPAD_DOWN) {
return tryMoveSelection(lm, 1);
} else if (keyCode == KeyEvent.KEYCODE_DPAD_UP) {
return tryMoveSelection(lm, -1);
}
}
return false;
}
});
}
private boolean tryMoveSelection(RecyclerView.LayoutManager lm, int direction) {
int tryFocusItem = focusedItem + direction;
// If still within valid bounds, move the selection, notify to redraw, and scroll
if (tryFocusItem >= 0 && tryFocusItem < getItemCount()) {
notifyItemChanged(focusedItem);
focusedItem = tryFocusItem;
notifyItemChanged(focusedItem);
lm.scrollToPosition(focusedItem);
return true;
}
return false;
}
@Override
public void onBindViewHolder(VH viewHolder, int i) {
// Set selected state; use a state list drawable to style the view
viewHolder.itemView.setSelected(focusedItem == i);
}
public class ViewHolder extends RecyclerView.ViewHolder {
public ViewHolder(View itemView) {
super(itemView);
// Handle item click and set the selection
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// Redraw the old selection and the new
notifyItemChanged(focusedItem);
focusedItem = mRecyclerView.getChildPosition(v);
notifyItemChanged(focusedItem);
}
});
}
}
}
viewHolder.mRlPrince.setOnTouchListener(new View.OnTouchListener() {
@Override public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN){
viewHolder.mRlPrince.setBackgroundColor(Color.parseColor("#f8f8f8"));
}if (event.getAction()==MotionEvent.ACTION_UP){
viewHolder.mRlPrince.setBackgroundColor(Color.WHITE);
}
return false;
}
});
Add :
android:background="?android:attr/selectableItemBackground"
in item.xml
Adding android:background="?android:attr/selectableItemBackground" to my_list_item.xml's root layout seems to work for me (assuming you want the default selection colour).
Also make sure the root layout's android:layout_width is match_parent rather than wrap_content to ensure that the whole row is selectable.
Set clickable, focusable, focusableInTouchMode to true in all elements of RecyclerView "list".
If nothing of this works for you, like it didn't for me, use this code:
android:foreground="?android:attr/selectableItemBackground"
The trick is in android:foreground attribute...