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我有一个Text我想成为的控件DragSource。如果您突出显示一些文本然后拖动您的选择，它会起作用。但是，我希望能够拖动Text控件的全部内容，而不是突出显示所有内容然后拖动它。例如，用户应该能够从小Text部件的背景单击和拖动。

下面是一个最小的例子：

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

public class BrowseDragExample {

public static void main(String[] args) {
    // put together the SWT main loop
    final Display display = Display.getDefault();
    display.syncExec(new Runnable() {
        @Override
        public void run() {
            Shell shell = new Shell(display, SWT.SHELL_TRIM);
            initializeGui(shell);

            //open the shell
            shell.open();

            //run the event loop
            while (!shell.isDisposed()) {
                if (!display.readAndDispatch()) {
                    display.sleep();
                }
            }
        }
    });
}

// creates the gui
private static void initializeGui(Composite parent) {
    GridLayout layout = new GridLayout(3, false);
    parent.setLayout(layout);

    Label infoLbl = new Label(parent, SWT.WRAP);
    GridData gd = new GridData();
    gd.grabExcessHorizontalSpace = true;
    gd.horizontalAlignment = SWT.FILL;
    gd.horizontalSpan = 3;
    infoLbl.setLayoutData(gd);
    infoLbl.setText("You should be able to drag text from one box to another, using either the Text, the ToolBar, or the Label.");

    addToolBarPair(parent);
    addToolBarPair(parent);
}

private static void addToolBarPair(Composite parent) {
    // make the text element
    final Text text = new Text(parent, SWT.SINGLE | SWT.BORDER);
    GridData gd = new GridData();
    gd.grabExcessHorizontalSpace = true;
    gd.horizontalAlignment = SWT.FILL;
    text.setLayoutData(gd);

    // make the toolbar element
    ToolBar toolbar = new ToolBar(parent, SWT.NONE);
    ToolItem toolItem = new ToolItem(toolbar, SWT.PUSH);
    toolItem.setText("Toolbar DND");

    // make the label element
    Label label = new Label(parent, SWT.NONE);
    label.setText("Label DND");

    // listener for drags
    DragSourceListener dragListener = new DragSourceListener() {
        @Override public void dragStart(DragSourceEvent e) {}
        @Override public void dragFinished(DragSourceEvent e) {}
        @Override
        public void dragSetData(DragSourceEvent e) {
            e.data = text.getText();
        }
    };

    // listener for drops
    DropTargetListener dropListener = new DropTargetListener() {
        @Override public void dragEnter(DropTargetEvent e) {
            e.detail = DND.DROP_COPY;
        }
        @Override public void dragLeave(DropTargetEvent e) {}
        @Override public void dragOperationChanged(DropTargetEvent e) {}
        @Override public void dragOver(DropTargetEvent e) {}
        @Override public void dropAccept(DropTargetEvent e) {}
        @Override public void drop(DropTargetEvent e) {
            String data = (String) e.data;
            text.setText(data);
        }
    };

    // assign these listeners for each control
    addDragSupport(text,    dragListener);
    addDragSupport(toolbar, dragListener);
    addDragSupport(label,   dragListener);

    addDropSupport(text,    dropListener);
    addDropSupport(toolbar, dropListener);
    addDropSupport(label,   dropListener);
}

private static void addDragSupport(Control control, DragSourceListener listener) {
    DragSource dragSource = new DragSource(control, DND.DROP_COPY);
    dragSource.setTransfer(new Transfer[]{TextTransfer.getInstance()});
    dragSource.addDragListener(listener);
}

private static void addDropSupport(Control control, DropTargetListener listener) {
    DropTarget dropTarget = new DropTarget(control, DND.DROP_COPY);
    dropTarget.setTransfer(new Transfer[]{TextTransfer.getInstance()});
    dropTarget.addDropListener(listener);
}
}
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