Eclipse Cookbook

9.1. Creating Message Boxes

Problem

You need to send a message to the user and/or get a little feedback from the user.

Solution

Use the SWT MessageBox class to create a message box, and check the return value from its open method to determine which button the user clicked.

Discussion

Here are the MessageBox class’s methods:

String getMessage( )

Returns the dialog’s message

int open( )

Makes the dialog visible

void setMessage(String string)

Sets the dialog’s message

You create a message box by passing the current shell to the MessageBox constructor, as well as the style you want to use: MessageBox(Shell parent, int style). Here are some common styles to use:

• SWT.ICON_ERROR

• SWT.ICON_INFORMATION

• SWT.ICON_QUESTION

• SWT.ICON_WARNING

• SWT.ICON_WORKING

• SWT.OK

• SWT.OK | SWT.CANCEL

• SWT.YES | SWT.NO

• SWT.YES | SWT.NO | SWT.CANCEL

• SWT.RETRY | SWT.CANCEL

• SWT.ABORT | SWT.RETRY | SWT.IGNORE.

You use the message box’s open method to display it; when the message box is closed, compare this method’s int return value to one of the preceding styles such as SWT.YES, SWT.NO, or SWT.CANCEL to determine which button was clicked.