/*
* 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 <http://www.gnu.org/licenses/>.
*/
package com.alee.extended.tab;
import com.alee.laf.tabbedpane.WebTabbedPane;
import com.alee.managers.log.Log;
import com.alee.utils.SwingUtils;
import javax.swing.*;
import java.awt.*;
import java.awt.datatransfer.Transferable;
import java.awt.event.InputEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
/**
* Custom TransferHandler for DocumentData object.
* This TransferHandler is made specially for WebDocumentPane component.
*
* @author Mikle Garin
* @see <a href="https://github.com/mgarin/weblaf/wiki/How-to-use-WebDocumentPane">How to use WebDocumentPane</a>
* @see com.alee.extended.tab.WebDocumentPane
*/
public class DocumentDragHandler extends TransferHandler
{
/**
* Distance from pane side within which drop is determined as a split action.
*/
private static final int dropSize = 40;
/**
* PaneData to which this TransferHandler is attached.
*/
protected final PaneData paneData;
/**
* WebTabbedPane from PaneData.
*/
protected final WebTabbedPane tabbedPane;
/**
* Dragged away document index.
* Used to restore document position if drag is cancelled for some reason.
*/
protected int documentIndex = -1;
/**
* Dragged document.
*/
protected DocumentData document = null;
/**
* Constructs new DocumentDragHandler for the specified PaneData.
*
* @param paneData PaneData
*/
public DocumentDragHandler ( final PaneData paneData )
{
super ();
this.paneData = paneData;
this.tabbedPane = paneData.getTabbedPane ();
}
/**
* {@inheritDoc}
*/
@Override
public int getSourceActions ( final JComponent c )
{
return MOVE;
}
/**
* {@inheritDoc}
*/
@Override
public void exportAsDrag ( final JComponent comp, final InputEvent e, final int action )
{
if ( e instanceof MouseEvent && action == MOVE )
{
// Find dragged document
final MouseEvent me = ( MouseEvent ) e;
final int index = tabbedPane.indexAtLocation ( me.getX (), me.getY () );
if ( index != -1 )
{
// Check whether it can be dragged
final DocumentData documentData = paneData.get ( index );
if ( documentData.isDraggable () )
{
// Perform export
documentIndex = index;
document = documentData;
super.exportAsDrag ( comp, e, action );
paneData.getDocumentPane ().checkSelection ();
}
}
}
}
/**
* {@inheritDoc}
*/
@Override
protected Transferable createTransferable ( final JComponent c )
{
if ( document != null )
{
paneData.remove ( document );
return new DocumentTransferable ( document );
}
else
{
return null;
}
}
/**
* {@inheritDoc}
*/
@Override
protected void exportDone ( final JComponent source, final Transferable data, final int action )
{
// Checking whether new location for the document was found or not
final WebDocumentPane documentPane = paneData.getDocumentPane ();
if ( !documentPane.isDragBetweenPanesEnabled () && documentPane.getDocument ( document.getId () ) == null )
{
// We cannot drag to other document pane and yet document is not in this pane
// That means that it was dragged out somewhere and didn't find a new place
// In this case we simply restore the document into this pane
paneData.add ( document, documentIndex );
paneData.setSelected ( document );
}
// Merging this pane if it has not more documents after drag
if ( paneData.count () == 0 )
{
paneData.getDocumentPane ().merge ( paneData );
}
// Clearing dragged document
documentIndex = -1;
document = null;
}
/**
* {@inheritDoc}
*/
@Override
public boolean canImport ( final TransferSupport support )
{
try
{
return support.getTransferable ().isDataFlavorSupported ( DocumentTransferable.flavor ) &&
support.getTransferable ().getTransferData ( DocumentTransferable.flavor ) != null;
}
catch ( final Throwable e )
{
Log.error ( this, e );
return false;
}
}
/**
* {@inheritDoc}
*/
@Override
public boolean importData ( final TransferSupport support )
{
try
{
// Retrieving transferred data
final Object data = support.getTransferable ().getTransferData ( DocumentTransferable.flavor );
final DocumentData document = ( DocumentData ) data;
// We need to check where exactly document was dropped
// Here are the options what might happen:
// 1. Dropped in the middle of tabbed pane - simply add document to end
// 2. Dropped onto tabs - add it between existing documents
// 3. Dropped on side (N px from the side) - split this pane
final Point dp = support.getDropLocation ().getDropPoint ();
final WebTabbedPane pane = ( WebTabbedPane ) support.getComponent ();
final int index = pane.getTabAt ( dp );
if ( index != -1 )
{
// Dropped on one of tabs, inserting
final Rectangle tb = pane.getBoundsAt ( index );
final int di = dp.x < tb.x + tb.width / 2 ? index : index + 1;
paneData.add ( document, di );
paneData.setSelected ( document );
checkFocusState ( paneData );
}
else
{
int dropSide = -1;
if ( paneData.getDocumentPane ().isSplitEnabled () && pane.getTabCount () > 0 )
{
final int tabPlacement = pane.getTabPlacement ();
final int w = pane.getWidth ();
final int h = pane.getHeight ();
if ( tabPlacement != SwingConstants.TOP && new Rectangle ( 0, 0, w, dropSize ).contains ( dp ) )
{
dropSide = SwingConstants.TOP;
}
else if ( tabPlacement != SwingConstants.BOTTOM && new Rectangle ( 0, h - dropSize, w, dropSize ).contains ( dp ) )
{
dropSide = SwingConstants.BOTTOM;
}
else if ( tabPlacement != SwingConstants.LEFT && new Rectangle ( 0, 0, dropSize, h ).contains ( dp ) )
{
dropSide = SwingConstants.LEFT;
}
else if ( tabPlacement != SwingConstants.RIGHT && new Rectangle ( w - dropSize, 0, dropSize, h ).contains ( dp ) )
{
dropSide = SwingConstants.RIGHT;
}
}
if ( dropSide != -1 )
{
// Dropped on the side of tabbed pane, splitting
final PaneData otherPane = paneData.getDocumentPane ().split ( paneData, document, dropSide );
otherPane.setSelected ( document );
checkFocusState ( otherPane );
}
else
{
// Dropped somewhere in the middle of tabbed pane, adding
paneData.add ( document );
paneData.setSelected ( document );
checkFocusState ( paneData );
}
}
return true;
}
catch ( final Throwable e )
{
Log.error ( this, e );
return false;
}
}
/**
* Special method to transfer focus properly after drag finishes.
*
* @param paneData pane to transfer focus into
*/
protected void checkFocusState ( final PaneData paneData )
{
// We have to perform focus transfer AFTER the drag ends, otherwise focus may be lost again
// That happens due to splits/tabbed panes removal in the process
SwingUtilities.invokeLater ( new Runnable ()
{
@Override
public void run ()
{
final WebTabbedPane pane = paneData.getTabbedPane ();
if ( !SwingUtils.hasFocusOwner ( pane ) )
{
final Component c = pane.getSelectedComponent ();
if ( c.isFocusable () || c instanceof Container && SwingUtils.hasFocusableComponent ( ( Container ) c ) )
{
pane.transferFocus ();
}
else
{
pane.requestFocusInWindow ();
}
}
}
} );
}
/**
* Quick drag handler installation method.
*
* @param paneData pane into which this drag handler should be installed
*/
public static void install ( final PaneData paneData )
{
final WebTabbedPane tabbedPane = paneData.getTabbedPane ();
final MouseAdapter dragAdapter = new MouseAdapter ()
{
protected boolean readyToDrag = false;
@Override
public void mousePressed ( final MouseEvent e )
{
readyToDrag = paneData.getDocumentPane ().isDragEnabled () && SwingUtils.isLeftMouseButton ( e );
}
@Override
public void mouseDragged ( final MouseEvent e )
{
if ( readyToDrag )
{
readyToDrag = false;
tabbedPane.getTransferHandler ().exportAsDrag ( tabbedPane, e, TransferHandler.MOVE );
}
}
@Override
public void mouseReleased ( final MouseEvent e )
{
readyToDrag = false;
}
};
tabbedPane.addMouseListener ( dragAdapter );
tabbedPane.addMouseMotionListener ( dragAdapter );
tabbedPane.setTransferHandler ( new DocumentDragHandler ( paneData ) );
}
}