ArrayIndexOutOfBoundsException when populating RecyclerView

Question

I am getting an error every so often when I try to populate my RecyclerView but the error seems to happening internally in the StaggeredGridLayoutManager.

Answer 1

This bug has been solved by google in version 21.0.2:

compile "com.android.support:support-v4:21.0.2"
compile "com.android.support:recyclerview-v7:21.0.2"

Answer 2

This crash happen when you try to notifyDataSetChanged/notifyItemRemoved/Added/change while RecyclerView isComputingLayout

This case may happen if you have some custom logic to change adapter contents in response to a View callback

In these cases, you should just postpone the change using a Handler

DON'T notify change until RecyclerView.isComputingLayout() return false.

 /**
     * Returns whether RecyclerView is currently computing a layout.
     * <p>
     * If this method returns true, it means that RecyclerView is in a lockdown state and any
     * attempt to update adapter contents will result in an exception because adapter contents
     * cannot be changed while RecyclerView is trying to compute the layout.
     * <p>
     * It is very unlikely that your code will be running during this state as it is
     * called by the framework when a layout traversal happens or RecyclerView starts to scroll
     * in response to system events (touch, accessibility etc).
     * <p>
     * This case may happen if you have some custom logic to change adapter contents in
     * response to a View callback (e.g. focus change callback) which might be triggered during a
     * layout calculation. In these cases, you should just postpone the change using a Handler or a
     * similar mechanism.
     *
     * @return <code>true</code> if RecyclerView is currently computing a layout, <code>false</code>
     *         otherwise
     */
    public boolean isComputingLayout() {
        return mLayoutOrScrollCounter > 0;
    }

Answer 3

I think this problem is triggered by https://code.google.com/p/android/issues/detail?id=77846. Can you replace notifyDataSetChanged calls with specific notify events (notifyItemRemoved/Added) and see if you can reproduce it?