com.alee.managers.drag.DragManager Maven / Gradle / Ivy
/*
* This file is part of WebLookAndFeel library.
*
* WebLookAndFeel library is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* WebLookAndFeel library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with WebLookAndFeel library. If not, see dragListeners =
new WeakComponentDataList ( "DragManager.DragListener", 50 );
/**
* Drag view handlers map.
*
* @see DragViewHandler
*/
private static final Map> viewHandlers = new HashMap> ();
/**
* Whether or not something is being dragged right now.
*/
private static boolean dragging = false;
/**
* Drag operation data flavors.
*/
private static DataFlavor[] flavors = null;
/**
* Currently dragged transferable.
*/
private static Transferable transferable = null;
/**
* Dragged object representation variables.
*/
private static WebGlassPane glassPane;
private static Object data;
private static BufferedImage view;
private static DragViewHandler dragViewHandler;
/**
* Whether manager is initialized or not.
*/
private static boolean initialized = false;
/**
* Initializes manager if it wasn't already initialized.
*/
public static synchronized void initialize ()
{
// To avoid more than one initialization
if ( !initialized )
{
// Remember that initialization happened
initialized = true;
// Global drag listener
final DragSourceAdapter dsa = new DragSourceAdapter ()
{
/**
* Informs about drag operation start.
*
* @param event drag event
*/
protected void dragStarted ( final DragSourceDragEvent event )
{
// Deciding on enter what to display for this kind of data
final DragSourceContext dsc = event.getDragSourceContext ();
final Transferable transferable = dsc.getTransferable ();
final DataFlavor[] flavors = transferable.getTransferDataFlavors ();
for ( final DataFlavor flavor : flavors )
{
if ( viewHandlers.containsKey ( flavor ) )
{
try
{
data = transferable.getTransferData ( flavor );
for ( final DragViewHandler handler : viewHandlers.get ( flavor ) )
{
if ( handler.supports ( data, event ) )
{
dragViewHandler = handler;
break;
}
}
if ( dragViewHandler != null )
{
view = dragViewHandler.getView ( data, event );
glassPane = GlassPaneManager.getGlassPane ( dsc.getComponent () );
glassPane.setPaintedImage ( view, getLocation ( glassPane, event, view ) );
break;
}
}
catch ( final Exception e )
{
LoggerFactory.getLogger ( DragManager.class ).error ( e.toString (), e );
}
}
}
// Marking drag operation
DragManager.transferable = transferable;
DragManager.flavors = flavors;
DragManager.dragging = true;
// Informing dragListeners
dragListeners.forEachData ( new BiConsumer ()
{
@Override
public void accept ( final JComponent component, final DragListener dragListener )
{
dragListener.started ( event );
}
} );
}
@Override
public void dragEnter ( final DragSourceDragEvent event )
{
// Informing dragListeners
dragListeners.forEachData ( new BiConsumer ()
{
@Override
public void accept ( final JComponent component, final DragListener dragListener )
{
dragListener.entered ( event );
}
} );
}
@Override
public void dragExit ( final DragSourceEvent event )
{
// Informing dragListeners
dragListeners.forEachData ( new BiConsumer ()
{
@Override
public void accept ( final JComponent component, final DragListener dragListener )
{
dragListener.exited ( event );
}
} );
}
@Override
public void dragMouseMoved ( final DragSourceDragEvent event )
{
// Create synthetic drag start event
// This is required because there is no drag start even in default listener
if ( !dragging )
{
dragStarted ( event );
}
// Move displayed data
if ( view != null )
{
final WebGlassPane gp = GlassPaneManager.getGlassPane ( event.getDragSourceContext ().getComponent () );
if ( gp != glassPane )
{
glassPane.clearPaintedImage ();
glassPane = gp;
}
glassPane.setPaintedImage ( view, getLocation ( glassPane, event, view ) );
}
// Informing dragListeners
dragListeners.forEachData ( new BiConsumer ()
{
@Override
public void accept ( final JComponent component, final DragListener dragListener )
{
dragListener.moved ( event );
}
} );
}
@Override
public void dragDropEnd ( final DragSourceDropEvent event )
{
// Marking drag operation
DragManager.dragging = false;
DragManager.flavors = null;
DragManager.transferable = null;
// Cleanup displayed data
if ( view != null )
{
dragViewHandler.dragEnded ( data, event );
glassPane.clearPaintedImage ();
glassPane = null;
data = null;
view = null;
dragViewHandler = null;
}
// Informing dragListeners
dragListeners.forEachData ( new BiConsumer ()
{
@Override
public void accept ( final JComponent component, final DragListener dragListener )
{
dragListener.finished ( event );
}
} );
}
/**
* Returns preferred dragged element location on glass pane.
*
* @param gp glass pane
* @param dsde drag source drag event
* @param view resulting view of the dragged object
* @return preferred dragged element location on glass pane
*/
public Point getLocation ( final WebGlassPane gp, final DragSourceDragEvent dsde, final BufferedImage view )
{
final Point mp = CoreSwingUtils.getMouseLocation ( gp );
final Point vp = dragViewHandler.getViewRelativeLocation ( data, dsde, view );
return new Point ( mp.x + vp.x, mp.y + vp.y );
}
};
// Listeners could only be registered on non-headless environment
if ( !GraphicsEnvironment.isHeadless () )
{
DragSource.getDefaultDragSource ().addDragSourceListener ( dsa );
DragSource.getDefaultDragSource ().addDragSourceMotionListener ( dsa );
}
}
}
/**
* Returns whether or not something is being dragged right now within the application.
*
* @return true if something is being dragged right now within the application, false otherwise
*/
public static boolean isDragging ()
{
return dragging;
}
/**
* Returns whether or not something with the specified data flavor is being dragged right now within the application.
*
* @param flavor data flavor
* @return true if something with the specified data flavor is being dragged right now within the application, false otherwise
*/
public static boolean isDragging ( final DataFlavor flavor )
{
return dragging && ArrayUtils.contains ( flavor, flavors );
}
/**
* Returns data flavors of the current drag operation.
*
* @return data flavors of the current drag operation
*/
public static DataFlavor[] getFlavors ()
{
return dragging ? flavors : null;
}
/**
* Returns currently dragged transferable.
*
* @return currently dragged transferable
*/
public static Transferable getTransferable ()
{
return transferable;
}
/**
* Registers {@link DragViewHandler}.
*
* @param handler {@link DragViewHandler} to register
*/
public static void registerViewHandler ( final DragViewHandler handler )
{
final DataFlavor flavor = handler.getObjectFlavor ();
List handlers = viewHandlers.get ( flavor );
if ( handlers == null )
{
handlers = new ArrayList ( 1 );
viewHandlers.put ( flavor, handlers );
}
handlers.add ( handler );
}
/**
* Unregisters {@link DragViewHandler}.
*
* @param handler {@link DragViewHandler} to unregister
*/
public static void unregisterViewHandler ( final DragViewHandler handler )
{
final List handlers = viewHandlers.get ( handler.getObjectFlavor () );
if ( handlers != null )
{
handlers.remove ( handler );
}
}
/**
* Adds {@link DragListener} for the specified {@link JComponent}.
*
* @param component {@link JComponent} to add {@link DragListener} for
* @param listener {@link DragListener} to add
*/
public static void addDragListener ( final JComponent component, final DragListener listener )
{
dragListeners.add ( component, listener );
}
/**
* Removes {@link DragListener} from the specified {@link JComponent}.
*
* @param component {@link JComponent} to remove {@link DragListener} from
* @param listener {@link DragListener} to remove
*/
public static void removeDragListener ( final JComponent component, final DragListener listener )
{
dragListeners.remove ( component, listener );
}
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