org.eclipse.swt.snippets.Snippet91.java Source code

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Here is the source code for org.eclipse.swt.snippets.Snippet91.java

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/*******************************************************************************
 * Copyright (c) 2000, 2013 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;

/*
 * Drag and Drop example snippet: drag leaf items in a tree
 *
 * 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.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class Snippet91 {

    public static void main(String[] args) {

        final Display display = new Display();
        final Shell shell = new Shell(display);
        shell.setText("Snippet 91");
        shell.setLayout(new FillLayout());
        final Tree tree = new Tree(shell, SWT.BORDER);
        for (int i = 0; i < 3; i++) {
            TreeItem item = new TreeItem(tree, SWT.NONE);
            item.setText("item " + i);
            for (int j = 0; j < 3; j++) {
                TreeItem subItem = new TreeItem(item, SWT.NONE);
                subItem.setText("item " + i + " " + j);
                for (int k = 0; k < 3; k++) {
                    TreeItem subsubItem = new TreeItem(subItem, SWT.NONE);
                    subsubItem.setText("item " + i + " " + j + " " + k);
                }
            }
        }

        Transfer[] types = new Transfer[] { TextTransfer.getInstance() };
        int operations = DND.DROP_MOVE | DND.DROP_COPY | DND.DROP_LINK;

        final DragSource source = new DragSource(tree, operations);
        source.setTransfer(types);
        final TreeItem[] dragSourceItem = new TreeItem[1];
        source.addDragListener(new DragSourceListener() {
            @Override
            public void dragStart(DragSourceEvent event) {
                TreeItem[] selection = tree.getSelection();
                if (selection.length > 0 && selection[0].getItemCount() == 0) {
                    event.doit = true;
                    dragSourceItem[0] = selection[0];
                } else {
                    event.doit = false;
                }
            }

            @Override
            public void dragSetData(DragSourceEvent event) {
                event.data = dragSourceItem[0].getText();
            }

            @Override
            public void dragFinished(DragSourceEvent event) {
                if (event.detail == DND.DROP_MOVE)
                    dragSourceItem[0].dispose();
                dragSourceItem[0] = null;
            }
        });

        DropTarget target = new DropTarget(tree, operations);
        target.setTransfer(types);
        target.addDropListener(new DropTargetAdapter() {
            @Override
            public void dragOver(DropTargetEvent event) {
                event.feedback = DND.FEEDBACK_EXPAND | DND.FEEDBACK_SCROLL;
                if (event.item != null) {
                    TreeItem item = (TreeItem) event.item;
                    Point pt = display.map(null, tree, event.x, event.y);
                    Rectangle bounds = item.getBounds();
                    if (pt.y < bounds.y + bounds.height / 3) {
                        event.feedback |= DND.FEEDBACK_INSERT_BEFORE;
                    } else if (pt.y > bounds.y + 2 * bounds.height / 3) {
                        event.feedback |= DND.FEEDBACK_INSERT_AFTER;
                    } else {
                        event.feedback |= DND.FEEDBACK_SELECT;
                    }
                }
            }

            @Override
            public void drop(DropTargetEvent event) {
                if (event.data == null) {
                    event.detail = DND.DROP_NONE;
                    return;
                }
                String text = (String) event.data;
                if (event.item == null) {
                    TreeItem item = new TreeItem(tree, SWT.NONE);
                    item.setText(text);
                } else {
                    TreeItem item = (TreeItem) event.item;
                    Point pt = display.map(null, tree, event.x, event.y);
                    Rectangle bounds = item.getBounds();
                    TreeItem parent = item.getParentItem();
                    if (parent != null) {
                        TreeItem[] items = parent.getItems();
                        int index = 0;
                        for (int i = 0; i < items.length; i++) {
                            if (items[i] == item) {
                                index = i;
                                break;
                            }
                        }
                        if (pt.y < bounds.y + bounds.height / 3) {
                            TreeItem newItem = new TreeItem(parent, SWT.NONE, index);
                            newItem.setText(text);
                        } else if (pt.y > bounds.y + 2 * bounds.height / 3) {
                            TreeItem newItem = new TreeItem(parent, SWT.NONE, index + 1);
                            newItem.setText(text);
                        } else {
                            TreeItem newItem = new TreeItem(item, SWT.NONE);
                            newItem.setText(text);
                        }

                    } else {
                        TreeItem[] items = tree.getItems();
                        int index = 0;
                        for (int i = 0; i < items.length; i++) {
                            if (items[i] == item) {
                                index = i;
                                break;
                            }
                        }
                        if (pt.y < bounds.y + bounds.height / 3) {
                            TreeItem newItem = new TreeItem(tree, SWT.NONE, index);
                            newItem.setText(text);
                        } else if (pt.y > bounds.y + 2 * bounds.height / 3) {
                            TreeItem newItem = new TreeItem(tree, SWT.NONE, index + 1);
                            newItem.setText(text);
                        } else {
                            TreeItem newItem = new TreeItem(item, SWT.NONE);
                            newItem.setText(text);
                        }
                    }

                }
            }
        });

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