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SWT - display busy cursor

I am trying to change the cursor when starting an operation. I want the cursor to show busy until the operation is completed. I have a separate class for operatorListener. I'm not sure how to assign a cursor?

A call from the AplotBaseDialog class

listOp.addOperationListener(new MyOperationListener(this) {
    etc....
}

Separate class

 public abstract class MyOperationListener implements InterfaceAIFOperationListener {
   Cursor busyCursor = null;
   AplotBaseDialog w = null;

  public MyOperationListener(AplotBaseDialog win) {

  **Should this not be getCurrent?**
    busyCursor = new Cursor(Display.getCurrent(), SWT.CURSOR_WAIT);

    w = win;
  } // end constructor

  public void startOperation(String startMessage) {
     ** should this be getting a Shell form the AplotBaseDialog? **
     w.???.setCursor(busyCursor);

  } // end startOperation()

  public void endOperation() {
     try {
        endOperationImpl();
     }
     finally {
        w.???.setCursor(null);
     }
  } // end endOperation()

  abstract protected void endOperationImpl();
 } // end class MyOperationListener

EDIT

  plotButton.addSelectionListener(new SelectionAdapter() {
         public void widgetSelected(SelectionEvent e) {
            BusyIndicator.showWhile(Display.getDefault(), new Runnable(){
               public void run(){
                  startPrinterListOperation(); 
               }
             });
         }
   });

EDIT

 private void startPrinterListOperation() {

  listOp = new AplotPrinterListOperation(appReg.getString("aplot.message.GETPRINTERLIST"), session);
  listOp.addOperationListener(new MyOperationListener(this) {
     public void endOperationImpl() {
        try {
           printers.clear();
           printers.addAll((ArrayList<PrinterProfile>) listOp.getPrinters());
           Display.getDefault().asyncExec(new Runnable() {
              public void run() {

                 showAplotPlotterDialog();
              }
           });
        }
        finally {

           listOp.removeOperationListener(this);
           listOp = null;
        }
     }
  });
  session.queueOperation(listOp);


 } // end startPrinterListOperation()
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2 answers

This works for me:

private static boolean wait = false;

private static Cursor cursor = null;

public static void main(String[] args) {
    final Display display = new Display();
    final Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());

    Button button = new Button(shell, SWT.PUSH);
    button.setText("Change cursor");

    button.addListener(SWT.Selection, new Listener() {

        @Override
        public void handleEvent(Event arg0) {
            wait = !wait;

            if(cursor != null)
                cursor.dispose();

            cursor = wait ? new Cursor(display, SWT.CURSOR_WAIT) : new Cursor(display, SWT.CURSOR_ARROW);

            shell.setCursor(cursor);
        }
    });


    shell.setSize(200,200);
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch()) {
            display.sleep();
        }
    }
    display.dispose();

    if(cursor != null)
        cursor.dispose();
}

Just position the cursor of your containing shell through setCursor(Display, int).

If you do not want to change the cursor for the entire shell, use Compositeor Controlof your choice.

Remember that you must dispose()create each Cursorinstance that you created.

+4
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you can use

    BusyIndicator.showWhile(Display.getDefault(), new Runnable(){

    public void run(){
       //your code
    }
    });
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