Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2005 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ //package org.eclipse.swt.snippets; /* * Make a dropped data type depend on a target item in table * * For a list of all SWT example snippets see * http://www.eclipse.org/swt/snippets/ */ import java.io.File; import org.eclipse.swt.SWT; import org.eclipse.swt.dnd.DND; import org.eclipse.swt.dnd.DragSource; import org.eclipse.swt.dnd.DragSourceAdapter; import org.eclipse.swt.dnd.DragSourceEvent; import org.eclipse.swt.dnd.DropTarget; import org.eclipse.swt.dnd.DropTargetAdapter; import org.eclipse.swt.dnd.DropTargetEvent; import org.eclipse.swt.dnd.FileTransfer; import org.eclipse.swt.dnd.TextTransfer; import org.eclipse.swt.dnd.Transfer; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Table; import org.eclipse.swt.widgets.TableItem; public class DropTypeOnTable { public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setLayout(new FillLayout()); Label label1 = new Label(shell, SWT.BORDER); label1.setText("Drag Source"); final Table table = new Table(shell, SWT.BORDER); for (int i = 0; i < 4; i++) { TableItem item = new TableItem(table, SWT.NONE); if (i % 2 == 0) item.setText("Drop a file"); if (i % 2 == 1) item.setText("Drop text"); } DragSource dragSource = new DragSource(label1, DND.DROP_COPY); dragSource.setTransfer(new Transfer[] { TextTransfer.getInstance(), FileTransfer.getInstance() }); dragSource.addDragListener(new DragSourceAdapter() { public void dragSetData(DragSourceEvent event) { if (FileTransfer.getInstance().isSupportedType(event.dataType)) { File file = new File("temp"); event.data = new String[] { file.getAbsolutePath() }; } if (TextTransfer.getInstance().isSupportedType(event.dataType)) { event.data = "once upon a time"; } } }); DropTarget dropTarget = new DropTarget(table, DND.DROP_COPY | DND.DROP_DEFAULT); dropTarget.setTransfer(new Transfer[] { TextTransfer.getInstance(), FileTransfer.getInstance() }); dropTarget.addDropListener(new DropTargetAdapter() { FileTransfer fileTransfer = FileTransfer.getInstance(); TextTransfer textTransfer = TextTransfer.getInstance(); public void dragEnter(DropTargetEvent event) { if (event.detail == DND.DROP_DEFAULT) event.detail = DND.DROP_COPY; } public void dragOperationChanged(DropTargetEvent event) { if (event.detail == DND.DROP_DEFAULT) event.detail = DND.DROP_COPY; } public void dragOver(DropTargetEvent event) { event.detail = DND.DROP_NONE; TableItem item = (TableItem) event.item; if (item == null) return; int itemIndex = table.indexOf(item); if (itemIndex % 2 == 0) { int index = 0; while (index < event.dataTypes.length) { if (fileTransfer.isSupportedType(event.dataTypes[index])) break; index++; } if (index < event.dataTypes.length) { event.currentDataType = event.dataTypes[index]; event.detail = DND.DROP_COPY; return; } } else { int index = 0; while (index < event.dataTypes.length) { if (textTransfer.isSupportedType(event.dataTypes[index])) break; index++; } if (index < event.dataTypes.length) { event.currentDataType = event.dataTypes[index]; event.detail = DND.DROP_COPY; return; } } } public void drop(DropTargetEvent event) { TableItem item = (TableItem) event.item; if (item == null) { event.detail = DND.DROP_NONE; return; } if (fileTransfer.isSupportedType(event.currentDataType)) { String[] files = (String[]) event.data; if (files != null && files.length > 0) { item.setText(files[0]); } } if (textTransfer.isSupportedType(event.currentDataType)) { String text = (String) event.data; if (text != null) { item.setText(text); } } } }); shell.setSize(300, 150); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); } }