org.eclipse.swt.dnd.DropTarget Java Examples

/**
 * Returns the shell for the given widget. If the widget doesn't represent
 * a SWT object that manage a shell, <code>null</code> is returned.
 * @param widget the widget
 *
 * @return the shell for the given widget
 */
public static Shell getShell(Widget widget) {
	if (widget instanceof Control)
		return ((Control)widget).getShell();
	if (widget instanceof Caret)
		return ((Caret)widget).getParent().getShell();
	if (widget instanceof DragSource)
		return ((DragSource)widget).getControl().getShell();
	if (widget instanceof DropTarget)
		return ((DropTarget)widget).getControl().getShell();
	if (widget instanceof Menu)
		return ((Menu)widget).getParent().getShell();
	if (widget instanceof ScrollBar)
		return ((ScrollBar)widget).getParent().getShell();

	return null;
}
 

public static void onDrop(TableViewer table,
		Consumer<List<Descriptor>> fn) {
	Transfer transfer = ModelTransfer.getInstance();
	DropTarget target = new DropTarget(table.getTable(),
			DND.DROP_COPY | DND.DROP_MOVE | DND.DROP_DEFAULT);
	target.setTransfer(new Transfer[] { transfer });
	target.addDropListener(new DropTargetAdapter() {
		@Override
		public void drop(DropTargetEvent event) {
			if (!transfer.isSupportedType(event.currentDataType))
				return;
			var list = ModelTransfer.getDescriptors(event.data);
			fn.accept(list);
		}
	});
}
 

public static void addDropSupport(TreeViewer tree,
		Consumer<List<Descriptor>> handler) {
	Transfer transfer = ModelTransfer.getInstance();
	DropTarget dropTarget = new DropTarget(tree.getTree(), DND.DROP_COPY
			| DND.DROP_MOVE | DND.DROP_DEFAULT);
	dropTarget.setTransfer(new Transfer[] { transfer });
	dropTarget.addDropListener(new DropTargetAdapter() {
		@Override
		public void drop(DropTargetEvent event) {
			if (!transfer.isSupportedType(event.currentDataType))
				return;
			var list = ModelTransfer.getDescriptors(event.data);
			handler.accept(list);
		}
	});
}
 

/**
 * Register the provided target as {@link DropTarget} for a {@link PersistentObject}
 * @param target
 * @param r
 * @param colorizeControl whether the target control should change color during selection
 * @since 3.1.0
 */
public PersistentObjectDropTarget(String name, Control target, IReceiver r, boolean colorizeControl){
	if (colorizeControl) {
		normalColor = target.getBackground();
		highlightColor = target.getDisplay().getSystemColor(SWT.COLOR_RED);
	} else {
		normalColor = null;
		highlightColor = null;
	}
	
	this.name = name;
	mine = target;
	rc = r;
	DropTarget dtarget = new DropTarget(target, DND.DROP_COPY);
	final TextTransfer textTransfer = TextTransfer.getInstance();
	Transfer[] types = new Transfer[] {
		textTransfer
	};
	dtarget.setTransfer(types);
	dtarget.addDropListener(this);
}
 

/**
 * Register the provided target as {@link DropTarget} for a {@link PersistentObject}
 * @param target
 * @param r
 * @param colorizeControl whether the target control should change color during selection
 * @since 3.1.0
 */
public GenericObjectDropTarget(String name, Control target, IReceiver r, boolean colorizeControl){
	if (colorizeControl) {
		normalColor = target.getBackground();
		highlightColor = target.getDisplay().getSystemColor(SWT.COLOR_RED);
	} else {
		normalColor = null;
		highlightColor = null;
	}
	
	this.name = name;
	mine = target;
	rc = r;
	DropTarget dtarget = new DropTarget(target, DND.DROP_COPY);
	final TextTransfer textTransfer = TextTransfer.getInstance();
	Transfer[] types = new Transfer[] {
		textTransfer
	};
	dtarget.setTransfer(types);
	dtarget.addDropListener(this);
}
 

/**
 * Returns the shell for the given widget. If the widget doesn't represent
 * a SWT object that manage a shell, <code>null</code> is returned.
 * @param widget the widget
 *
 * @return the shell for the given widget
 */
public static Shell getShell(Widget widget) {
    if (widget instanceof Control) {
        return ((Control) widget).getShell();
    }
    if (widget instanceof Caret) {
        return ((Caret) widget).getParent().getShell();
    }
    if (widget instanceof DragSource) {
        return ((DragSource) widget).getControl().getShell();
    }
    if (widget instanceof DropTarget) {
        return ((DropTarget) widget).getControl().getShell();
    }
    if (widget instanceof Menu) {
        return ((Menu) widget).getParent().getShell();
    }
    if (widget instanceof ScrollBar) {
        return ((ScrollBar) widget).getParent().getShell();
    }

    return null;
}
 

@Override
public void createPartControl(Composite parent) {
	parent.setLayout(new FillLayout());
	this.container = parent;
	CellEditorGlobalActionHanlder.getInstance().setIActionBars(getViewSite().getActionBars());
	DropTarget target = new DropTarget(parent, DND.DROP_MOVE | DND.DROP_COPY);
	Transfer[] tfs = new Transfer[] { FileTransfer.getInstance() };
	target.setTransfer(tfs);
	target.addDropListener(new DropTargetAdapter() {
		@Override
		public void drop(DropTargetEvent event) {
			Object o = event.data;
			if (o instanceof String[]) {
				String[] s = (String[]) o;
				if (s.length == 0 && s[0] == null || s[0].length() == 0) {
					return;
				}
				File f = new File(s[0]);
				if (f.exists() && f.isFile()) {
					open(f);
				}
			}
		}
	});
}
 

/**
 * Returns the shell for the given widget. If the widget doesn't represent a SWT object that manage a shell,
 * <code>null</code> is returned.
 * 
 * @return the shell for the given widget
 */
public static Shell getShell(Widget widget)
{
	if (widget instanceof Control)
		return ((Control) widget).getShell();
	if (widget instanceof Caret)
		return ((Caret) widget).getParent().getShell();
	if (widget instanceof DragSource)
		return ((DragSource) widget).getControl().getShell();
	if (widget instanceof DropTarget)
		return ((DropTarget) widget).getControl().getShell();
	if (widget instanceof Menu)
		return ((Menu) widget).getParent().getShell();
	if (widget instanceof ScrollBar)
		return ((ScrollBar) widget).getParent().getShell();

	return null;
}
 

@Override
public void drop(DropTargetEvent event) {
	if (!URLTransfer.getInstance().isSupportedType(event.currentDataType)) {
		return;
	}
	final String url = getUrl(event.data);

	if (ExampleURLHandler.isValidExample(url)) {
		DropTarget source = (DropTarget) event.getSource();
		Display display = source.getDisplay();
		display.asyncExec(new Runnable() {
			public void run() {
				proceedInstallation(url);
			}
		});
	}
}
 

/**
 * Returns the shell for the given widget. If the widget doesn't represent a SWT object that manage a shell,
 * <code>null</code> is returned.
 * 
 * @param widget
 *            the widget
 * 
 * @return the shell for the given widget
 */
public static Shell getShell(Widget widget) {
	if (widget instanceof Control)
		return ((Control) widget).getShell();
	if (widget instanceof Caret)
		return ((Caret) widget).getParent().getShell();
	if (widget instanceof DragSource)
		return ((DragSource) widget).getControl().getShell();
	if (widget instanceof DropTarget)
		return ((DropTarget) widget).getControl().getShell();
	if (widget instanceof Menu)
		return ((Menu) widget).getParent().getShell();
	if (widget instanceof ScrollBar)
		return ((ScrollBar) widget).getParent().getShell();

	return null;
}
 

protected void registerWithExistingTarget(DropTarget target) {
	Transfer[] transfers = target.getTransfer();
	boolean exists = false;
	if (transfers != null) {
		for (Transfer transfer : transfers) {
			if (transfer instanceof URLTransfer) {
				exists = true;
				break;
			}
		}
		if (!exists) {
			Transfer[] newTransfers = new Transfer[transfers.length + 1];
			System.arraycopy(transfers, 0, newTransfers, 0, transfers.length);
			newTransfers[transfers.length] = URLTransfer.getInstance();
			target.setTransfer(newTransfers);
		}
	}
}
 

public void createPartControl(Composite parent) {
    //viewer
    this.parent = parent;
    documentListener = new ViewDocumentListener();
    tabfolder = new TabFolder(parent,0);
    tabfolder.addSelectionListener(new TabSelectionListener());
    viewer = new LogFileViewer(tabfolder,SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL);

    // DnD
    DropTarget target = new DropTarget(parent, DND.DROP_MOVE | DND.DROP_COPY | DND.DROP_LINK);
    target.setTransfer(new Transfer[] {FileTransfer.getInstance(), TextTransfer.getInstance()});
    target.addDropListener (new DropTargetAdapter() {
        public void dragEnter(DropTargetEvent e) {
            if (e.detail == DND.DROP_NONE)
                e.detail = DND.DROP_COPY;
        }
        public void drop(DropTargetEvent event) {
            if (event.data == null || ((String[])event.data).length < 1) {
                event.detail = DND.DROP_NONE;
                return;
            }
            //File file = new File(((String[])event.data)[0]);
            if (!checkAndOpenFile(LogFileType.LOGFILE_SYSTEM_FILE,((String[])event.data)[0], null, false))
                event.detail = DND.DROP_NONE;
        }
    });

    // fill the menues
    makeActions();
    hookContextMenu();
    contributeToActionBars();
    openAllLastOpenFiles();
}
 

@Override
public IStatus handleDrop(CommonDropAdapter dropAdapter,
		DropTargetEvent dropTargetEvent, Object target) {
	Navigator navigator = (Navigator) PlatformUI.getWorkbench()
			.getActiveWorkbenchWindow().getActivePage()
			.findView(Navigator.ID);
	DropTarget dropTarget = (DropTarget) dropTargetEvent.getSource();
	INavigationElement<?> targetElement = (INavigationElement<?>) target;
	if (dropTarget.getControl() == navigator.getCommonViewer().getTree())
		doIt(dropTargetEvent, targetElement);
	return null;
}
 

public IdentifiableDropTarget(Control target, IReceiver receiver){
	this.receiver = receiver;
	DropTarget dtarget = new DropTarget(target, DND.DROP_COPY);
	final TextTransfer textTransfer = TextTransfer.getInstance();
	Transfer[] types = new Transfer[] {
		textTransfer
	};
	dtarget.setTransfer(types);
	dtarget.addDropListener(this);
}
 

private void initDragDrop() {
    DragSource dragSource = new DragSource(this, DND.DROP_COPY | DND.DROP_MOVE);
    dragSource.addDragListener(new DragSourceAdapter());
    dragSource.setTransfer(new Transfer[] { org.eclipse.swt.dnd.TextTransfer.getInstance() });

    DropTarget dropTarget = new DropTarget(this, DND.DROP_COPY | DND.DROP_MOVE);
    dropTarget.setTransfer(new Transfer[] { LocalSelectionTransfer.getTransfer(),
            org.eclipse.swt.dnd.TextTransfer.getInstance() });
    dropTarget.addDropListener(new DragTargetAdapter());
}
 

protected void hookRecursive(Control child, DropTargetListener dropListener) {
	DropTarget childTarget = findDropTarget(child);
	if (childTarget != null) {
		registerWithExistingTarget(childTarget);
		registerDropListener(childTarget, dropListener);
	}
	if (child instanceof Composite) {
		Composite composite = (Composite) child;
		Control[] children = composite.getChildren();
		for (Control control : children) {
			hookRecursive(control, dropListener);
		}
	}
}
 

private void addDropListener(Composite parent) {
	LocalSelectionTransfer transfer = LocalSelectionTransfer.getTransfer();

	DropTargetAdapter dragAdapter = new DropTargetAdapter() {
		@Override
		public void drop(DropTargetEvent event) {
			Control droppedObj = (Control) ((StructuredSelection) transfer.getSelection()).getFirstElement();

			// Get the existing parent of the dragged control
			Composite oldParent = droppedObj.getParent();

			if (oldParent == parent) {
				return;
			}

			if  (droppedObj instanceof Label) {
				System.out.println("Dropped");
			}
			// handle the drop
			if (droppedObj instanceof Label) {
				Label droppedLabel = (Label) droppedObj;
				droppedLabel.setParent(parent); // Change parent
			}

			if (droppedObj instanceof Button) {
				Button droppedButton = (Button) droppedObj;
				droppedButton.setParent(parent); // Change parent
			}

			// request a layout pass
			oldParent.requestLayout();
			// If you change that to layout the layout will be correct
			parent.layout();
		}
	};

	DropTarget dropTarget = new DropTarget(parent, DND.DROP_MOVE | DND.DROP_COPY);
	dropTarget.setTransfer(new Transfer[] { transfer });
	dropTarget.addDropListener(dragAdapter);
}
 

public DropTarget createDropTarget ( final Transfer[] transfers, final DropTargetListener dropTargetListener )
{
    checkWidget ();

    final DropTarget target = new DropTarget ( this.chartArea, DND.DROP_DEFAULT | DND.DROP_COPY | DND.DROP_LINK );
    target.setTransfer ( transfers );
    target.addDropListener ( dropTargetListener );
    return target;
}
 

private void initDragAndDrop() {
	for (int i= 0; i < fAllViewers.length; i++) {
		addDragAdapters(fAllViewers[i]);
		addDropAdapters(fAllViewers[i]);
	}
	addDragAdapters(fMethodsViewer);
	fMethodsViewer.addDropSupport(DND.DROP_NONE, new Transfer[0], new DropTargetAdapter());

	//DND on empty hierarchy
	DropTarget dropTarget = new DropTarget(fPagebook, DND.DROP_MOVE | DND.DROP_COPY | DND.DROP_LINK | DND.DROP_DEFAULT);
	dropTarget.setTransfer(new Transfer[] { LocalSelectionTransfer.getInstance() });
	dropTarget.addDropListener(new TypeHierarchyTransferDropAdapter(this, fAllViewers[0]));
}
 

private void initDragAndDrop() {
    addDragAdapters(fCallHierarchyViewer);
    addDropAdapters(fCallHierarchyViewer);
    addDropAdapters(fLocationViewer);

    //dnd on empty hierarchy
    DropTarget dropTarget = new DropTarget(fPagebook, DND.DROP_MOVE | DND.DROP_COPY | DND.DROP_LINK | DND.DROP_DEFAULT);
    dropTarget.setTransfer(new Transfer[] { LocalSelectionTransfer.getInstance() });
    dropTarget.addDropListener(new CallHierarchyTransferDropAdapter(this, fCallHierarchyViewer));
}
 

@Override
protected void initializeDragAndDrop(ISourceViewer viewer)
{
	super.initializeDragAndDrop(viewer);

	// Adds snippet drag/drop support
	IDragAndDropService dndService = (IDragAndDropService) getSite().getService(IDragAndDropService.class);
	if (dndService == null)
	{
		return;
	}
	StyledText st = viewer.getTextWidget();
	DropTarget dropTarget = (DropTarget) st.getData(DND.DROP_TARGET_KEY);
	if (dropTarget != null)
	{
		Transfer[] transfers = dropTarget.getTransfer();
		List<Transfer> allTransfers = CollectionsUtil.newList(transfers);
		allTransfers.add(SnippetTransfer.getInstance());
		dropTarget.setTransfer(allTransfers.toArray(new Transfer[allTransfers.size()]));
		dropTarget.addDropListener(new SnippetDropTargetListener());
	}
	else
	{
		dndService.addMergedDropTarget(st, DND.DROP_COPY, new Transfer[] { SnippetTransfer.getInstance() },
				new SnippetDropTargetListener());
	}
}
 

protected DropTarget findDropTarget(Control control) {
	Object object = control.getData(DND.DROP_TARGET_KEY);
	if (object instanceof DropTarget) {
		return (DropTarget) object;
	}
	return null;
}
 

/**
 * @param parentComposite - the composite that holds all pictures
 * @param target - the drop target
 */
public MyDropTargetListener(Composite parentComposite, DropTarget target) {
    this.parentComposite = parentComposite;
    this.target = target;
}
 

public static void main(String[] args) {
	// setup the SWT window
	Display display = new Display();
	final Shell shell = new Shell(display);
	shell.setLayout(new FillLayout());
	shell.setText("Photo Shuffler");

	// initialize a parent composite with a grid layout manager
	Composite parent = new Composite(shell, SWT.NONE);
	GridLayout gridLayout = new GridLayout();
	gridLayout.numColumns = 2;
	gridLayout.marginWidth=20;
	parent.setLayout(gridLayout);

	// determine the path where the pictures are stored
	String path = System.getProperty("user.dir") + "/images/";
	// initialize an array with the photograph names

	File imageDir= new File(path);
	
	// loop over the photo array and establish all listeners
	List<File> files = Arrays.stream(imageDir.listFiles())
				 	.filter(f -> f.isFile() && f.getName().endsWith(".png"))
					.collect(Collectors.toList());
	
	for (File file : files) {
		// labels serve as containers for the images
		Label label = new Label(parent, SWT.NONE);
		Image img = new Image(display,file.getAbsolutePath());
		label.setImage(img);

		// enable each label to be draggable
		DragSource source = new DragSource(label, DND.DROP_NONE);
		source.setTransfer(TextTransfer.getInstance()); // varargs are supported as of 4.7
		// add a drag listener
		source.addDragListener(new MyDragSourceListener(parent, source));

		// enable each label to be a drop target
		DropTarget target = new DropTarget(label, DND.DROP_NONE);
		target.setTransfer(new Transfer[] { TextTransfer.getInstance() }); // varargs are not yet supported see https://git.eclipse.org/r/#/c/92236			// add a drop listener
		target.addDropListener(new MyDropTargetListener(parent, target));
	}

	// show the SWT window
	shell.pack();
	shell.open();
	while (!shell.isDisposed()) {
		if (!display.readAndDispatch())
			display.sleep();
	}
	// tear down the SWT window
	display.dispose();
}
 

public void dragEnter( DropTargetEvent event )
{
	// indicate a copy
	event.detail = DND.DROP_COPY;

	// check if valid expression
	// Get Data in a Java format
	// Since in Mac os x / Linux, the event.currentDataType.data is still
	// null, so here ignores validation under Mac os x /Linux.
	if ( Platform.OS_WIN32.equals( Platform.getOS( ) ) )
	{
		Object object = null;
		Transfer[] transferAgents = ( (DropTarget) event.widget ).getTransfer( );
		for ( int i = 0; i < transferAgents.length; i++ )
		{
			Transfer transfer = transferAgents[i];
			if ( transfer != null && transfer instanceof SimpleTextTransfer )
			{
				object = SimpleTextTransfer.getInstance( )
						.nativeToJava( event.currentDataType );
				break;
			}
		}
		if ( object != null )
		{
			// object is a binding name. expression is needed for
			// validation.
			ExpressionCodec expCodec = ChartModelHelper.instance( )
					.createExpressionCodec( );
			expCodec.setType( btnBuilder.getExpressionType( ) );
			expCodec.setBindingName( object.toString( ),
					btnBuilder.isCube( ) );
			if ( !DataDefinitionTextManager.getInstance( )
					.isValidExpression( txtDataDefn,
							expCodec.getExpression( ) ) )
			{
				event.detail = DND.DROP_NONE;
			}
		}
	}
}
 

protected void registerDropListener(DropTarget target, DropTargetListener dropListener) {
	target.removeDropListener(dropListener);
	target.addDropListener(dropListener);
}
 

public FilterViewer(Composite parent, int style, boolean isDialog) {
    super(parent, style);

    this.fIsDialog = isDialog;

    setLayout(new FillLayout());
    GridData gd = new GridData(SWT.FILL, SWT.FILL, true, true);
    setLayoutData(gd);

    final SashForm sash = new SashForm(this, SWT.HORIZONTAL);

    // Create the tree viewer to display the filter tree
    fViewer = new TreeViewer(sash, SWT.NONE);
    fViewer.setContentProvider(new FilterTreeContentProvider());
    fViewer.setLabelProvider(new FilterTreeLabelProvider());

    // Create the empty filter node properties panel
    fComposite = new Composite(sash, SWT.NONE);
    GridLayout gl = new GridLayout();
    gl.marginHeight = 0;
    gl.marginWidth = 0;
    fComposite.setLayout(gl);

    createContextMenu();

    fViewer.addSelectionChangedListener(event -> {
        if (!(event.getSelection().isEmpty()) && event.getSelection() instanceof IStructuredSelection) {
            // Update the filter node properties panel to the selection
            IStructuredSelection selection = (IStructuredSelection) event.getSelection();
            ITmfFilterTreeNode node = (ITmfFilterTreeNode) selection.getFirstElement();
            updateFilterNodeComposite(node);
        } else {
            updateFilterNodeComposite(null);
        }
    });

    fViewer.getTree().addPaintListener(e -> {
        TmfFilterTreeNode root = (TmfFilterTreeNode) fViewer.getInput();
        if (root == null || root.getChildrenCount() == 0) {
            e.gc.setForeground(FOREGROUND_COLOR);
            e.gc.drawText(Messages.FilterViewer_EmptyTreeHintText, 5, 0);
        }
    });

    int operations = DND.DROP_MOVE | DND.DROP_COPY;
    DragSource dragSource = new org.eclipse.swt.dnd.DragSource(fViewer.getTree(), operations);
    dragSource.setTransfer(new Transfer[] { LocalSelectionTransfer.getTransfer() });
    dragSource.addDragListener(new FilterDragSourceAdapter(this));
    DropTarget dropTarget = new DropTarget(fViewer.getTree(), operations);
    dropTarget.setTransfer(new Transfer[] { LocalSelectionTransfer.getTransfer() });
    dropTarget.addDropListener(new FilterDropTargetAdapter(this));
}
 

/**
 * Set a Drop Target and handle its disposal
 * <br/>
 * Should be called on {@link TableLifeCycleListener#EVENT_TABLELIFECYCLE_INITIALIZED} event trigger
 */
DropTarget createDropTarget(int style);