org.eclipse.swt.snippets.Snippet185.java Source code

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Here is the source code for org.eclipse.swt.snippets.Snippet185.java

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/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * 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.*;

import org.eclipse.swt.*;
import org.eclipse.swt.dnd.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class Snippet185 {

    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setText("Snippet 185");
        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(TextTransfer.getInstance(), FileTransfer.getInstance());
        dragSource.addDragListener(new DragSourceAdapter() {
            @Override
            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(TextTransfer.getInstance(), FileTransfer.getInstance());
        dropTarget.addDropListener(new DropTargetAdapter() {
            FileTransfer fileTransfer = FileTransfer.getInstance();
            TextTransfer textTransfer = TextTransfer.getInstance();

            @Override
            public void dragEnter(DropTargetEvent event) {
                if (event.detail == DND.DROP_DEFAULT)
                    event.detail = DND.DROP_COPY;
            }

            @Override
            public void dragOperationChanged(DropTargetEvent event) {
                if (event.detail == DND.DROP_DEFAULT)
                    event.detail = DND.DROP_COPY;
            }

            @Override
            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;
                    }
                }
            }

            @Override
            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();
    }
}