Drag and Drop: determine native data types available (motif only) : SWT Drag Drop « SWT « Java Tutorial






/*******************************************************************************
 * Copyright (c) 2000, 2004 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;
/*
 * Drag and Drop example snippet: determine native data types available (motif only)
 * NOTE: This snippet uses internal SWT packages that are
 * subject to change without notice.
 *
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 */
import org.eclipse.swt.*;
import org.eclipse.swt.dnd.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.motif.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class Snippet158 extends ByteArrayTransfer {

  private static Snippet158 _instance = new Snippet158();

  private int[] ids;

  private String[] names;

  public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    final Table control = new Table(shell, SWT.NONE);
    TableItem item = new TableItem(control, SWT.NONE);
    item.setText("Drag data over this site to see the native transfer type.");
    DropTarget target = new DropTarget(control, DND.DROP_DEFAULT | DND.DROP_COPY | DND.DROP_LINK
        | DND.DROP_MOVE);
    target.setTransfer(new Transfer[] { Snippet158.getInstance() });
    target.addDropListener(new DropTargetAdapter() {
      public void dragEnter(DropTargetEvent event) {
        String ops = "";
        if ((event.operations & DND.DROP_COPY) != 0)
          ops += "Copy;";
        if ((event.operations & DND.DROP_MOVE) != 0)
          ops += "Move;";
        if ((event.operations & DND.DROP_LINK) != 0)
          ops += "Link;";
        control.removeAll();
        TableItem item1 = new TableItem(control, SWT.NONE);
        item1.setText("Allowed Operations are " + ops);

        if (event.detail == DND.DROP_DEFAULT) {
          if ((event.operations & DND.DROP_COPY) != 0) {
            event.detail = DND.DROP_COPY;
          } else if ((event.operations & DND.DROP_LINK) != 0) {
            event.detail = DND.DROP_LINK;
          } else if ((event.operations & DND.DROP_MOVE) != 0) {
            event.detail = DND.DROP_MOVE;
          }
        }

        TransferData[] data = event.dataTypes;
        for (int i = 0; i < data.length; i++) {
          int id = data[i].type;
          String name = getNameFromId(id);
          TableItem item2 = new TableItem(control, SWT.NONE);
          item2.setText("Data type is " + id + " " + name);
        }
      }
    });

    shell.setSize(400, 400);
    shell.open();
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch())
        display.sleep();
    }
    display.dispose();
  }

  public static Snippet158 getInstance() {
    return _instance;
  }

  Snippet158() {
  }

  public void javaToNative(Object object, TransferData transferData) {
  }

  public Object nativeToJava(TransferData transferData) {
    return "Hello World";
  }

  protected String[] getTypeNames() {
    return names;
  }

  static int shellHandle;

  protected int[] getTypeIds() {
    if (ids == null) {
      Display display = Display.getCurrent();
      int widgetClass = OS.topLevelShellWidgetClass();
      shellHandle = OS.XtAppCreateShell(null, null, widgetClass, display.xDisplay, null, 0);
      OS.XtSetMappedWhenManaged(shellHandle, false);
      OS.XtRealizeWidget(shellHandle);

      ids = new int[840];
      names = new String[840];
      for (int i = 0; i < ids.length; i++) {
        ids[i] = i + i;
        names[i] = getNameFromId(i + 1);
      }
    }
    return ids;
  }

  static String getNameFromId(int id) {
    int xDisplay = OS.XtDisplay(shellHandle);
    int ptr = 0;
    try {
      ptr = OS.XmGetAtomName(xDisplay, id);
    } catch (Throwable t) {
    }
    if (ptr == 0)
      return "invalid " + id;
    int length = OS.strlen(ptr);
    byte[] nameBuf = new byte[length];
    OS.memmove(nameBuf, ptr, length);
    OS.XFree(ptr);
    return new String(Converter.mbcsToWcs(null, nameBuf)).toLowerCase();
  }
}








17.114.SWT Drag Drop
17.114.1.Dragging and Dropping
17.114.2.Drag selected text in Text to LabelDrag selected text in Text to Label
17.114.3.Drag and Drop inside TableDrag and Drop inside Table
17.114.4.Drag and Drop example snippet: determine data types available (win32 only)Drag and Drop example snippet: determine data types available (win32 only)
17.114.5.Drag and Drop: define a default operation (in this example, Copy)Drag and Drop: define a default operation (in this example, Copy)
17.114.6.Drag and Drop: define my own data transfer typeDrag and Drop: define my own data transfer type
17.114.7.Drag leaf items in a treeDrag leaf items in a tree
17.114.8.Drag text between two labelsDrag text between two labels
17.114.9.Drag and Drop: determine native data types available (motif only)
17.114.10.Make a dropped data type depend on a target item in tableMake a dropped data type depend on a target item in table