Bug 72297 [DnD] ViewerDropAdapter impossible to set DND.FEEDBACK_NONE
It is not possible to disable selection feedback in ViewerDropAdapter. There are setFeedbackEnabled(false) and setScrollExpandEnabled(false) methods to turn off the feedback effects. If those methods are used, selection feedback still provided. It is not possible to turn it off, elements are still selected when drag is over them. Overriding method; private void setFeedback(DropTargetEvent event, int location) { event.feedback = DND.FEEDBACK_NONE; } - does not chenge the feedback either. setFeedbackEnabled() should be extended to disable SELECTION feedback or new method created, setSelectionFeedback().
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ViewerDropAdapter.java
/**
     * Constant describing the position of the cursor relative 
     * to the target object.  This means the mouse is positioned
     * slightly before the target.
     * @see #getCurrentLocation()
     */
    public static final int LOCATION_BEFORE = 1;
    /**
     * Constant describing the position of the cursor relative 
     * to the target object.  This means the mouse is positioned
     * slightly after the target.
     * @see #getCurrentLocation()
     */
    public static final int LOCATION_AFTER = 2;
    /**
     * Constant describing the position of the cursor relative 
     * to the target object.  This means the mouse is positioned
     * directly on the target.
     * @see #getCurrentLocation()
     */
    public static final int LOCATION_ON = 3;
    /**
     * Constant describing the position of the cursor relative 
     * to the target object.  This means the mouse is not positioned
     * over or near any valid target.
     * @see #getCurrentLocation()
     */
    public static final int LOCATION_NONE = 4;
    /**