Android: How do I keep DrawerLayout from passing touch events to the underlying view

Question

I am using the Support library's DrawerLayout in my app. I noticed that, when I click on an empty area in my Drawer view, the underlying View (containing a ListView) receives the Touch event and reacts to it.

The onInterceptTouchEvent method of the DrawerLayout looks like this:

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    final int action = MotionEventCompat.getActionMasked(ev);

    // "|" used deliberately here; both methods should be invoked.
    final boolean interceptForDrag = mLeftDragger.shouldInterceptTouchEvent(ev) |
            mRightDragger.shouldInterceptTouchEvent(ev);

    boolean interceptForTap = false;

    switch (action) {
        case MotionEvent.ACTION_DOWN: {
            final float x = ev.getX();
            final float y = ev.getY();
            mInitialMotionX = x;
            mInitialMotionY = y;
            if (mScrimOpacity > 0 &&
                    isContentView(mLeftDragger.findTopChildUnder((int) x, (int) y))) {
                interceptForTap = true;
            }
            mDisallowInterceptRequested = false;
            mChildrenCanceledTouch = false;
            break;
        }

        case MotionEvent.ACTION_MOVE: {
            // If we cross the touch slop, don't perform the delayed peek for an edge touch.
            if (mLeftDragger.checkTouchSlop(ViewDragHelper.DIRECTION_ALL)) {
                mLeftCallback.removeCallbacks();
                mRightCallback.removeCallbacks();
            }
            break;
        }

        case MotionEvent.ACTION_CANCEL:
        case MotionEvent.ACTION_UP: {
            closeDrawers(true);
            mDisallowInterceptRequested = false;
            mChildrenCanceledTouch = false;
        }
    }

    return interceptForDrag || interceptForTap || hasPeekingDrawer() || mChildrenCanceledTouch;
}

My view with the DrawerLayout:

<android.support.v4.widget.DrawerLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/drawer_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <FrameLayout
            android:id="@+id/content"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"/>

    <FrameLayout
            android:id="@+id/sidebar_container"
            android:layout_width="300dp"
            android:layout_height="match_parent"
            android:layout_gravity="left"/>

</android.support.v4.widget.DrawerLayout>

What can I do, (if possible without extending the DrawerLayout class) to prevent this behaviour? As long as the drawer is open, I want no click events to reach the background view.

Answer 1

Set clickable to true on the drawer - it'll consume the touch.

<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/content_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

    <FrameLayout
        android:id="@+id/drawer_view"
        android:layout_width="300dp"
        android:clickable="true"
        android:importantForAccessibility="no"
        android:layout_height="match_parent"
        android:layout_gravity="left"/>

</android.support.v4.widget.DrawerLayout>

I added android:importantForAccessibility="no" because marking the drawer as interactive (clickable or focusable) will make the entire drawer visible to accessibility services like TalkBack.

This is not what you want (usually) - more often, items inside the drawer should be accessible to the services.

This attribute is only available on API 16+.