Field Detail

• ERROR

  public static final MessageType ERROR

  The Dialog shows an error message.

  You should use this kind of MessageDialog when an operation requested by the user cannot be successfully completed. However, if the operation that has caused the error is a background or periodic operation, you may want to consider displaying the error by other means, such as a Statusbar message, unless the error could result in data loss or other serious problems.

  You should present an OK Button to let user close the Dialog. Optionally, if the error can be immediately fixed, you may add a Button to launch the repair operation (a "Format..." Button in a "This disk is not formatted" alert, for example).

• INFO

  public static final MessageType INFO

  The Dialog shows an informational message.

  Only use this kind of messages for important information the user must know before continuing to use the application, or for information the user has requested. For less important information you shouldn't use a MessageDialog, but other informational Widgets such as a Statusbar.

  Consider using a single OK Button to let the user close the Dialog.

• OTHER

  public static final MessageType OTHER

  Use this when the predefined MessageTypes are not suitable for your MessageDialog. In that cases you may want to add a custom icon to the Dialog.

• QUESTION

  public static final MessageType QUESTION

  The Dialog present a choice to the user.

  Use this type to present Dialogs that ask users to take a non serious decision. Usually you will provide YES_NO Buttons to let the user express his choice.

  If the choice can have a serious impact in the application, such as the lost of data, a WARNING message is a better alternative.

• WARNING

  public static final MessageType WARNING

  The Dialog shows a warning message.

  A typical usage of these messages is to request user confirmation to a potentially dangerous action. You should present such messages when the the task that is going to be executed may destroy user data, create a security risk, or take more than 30 seconds of user effort to recover from if it was selected in error.

  While simple warning messages can be correctly handled by OK_CANCEL Buttons, in many cases you may want to provide a Help Button to give the user more information about the risk, or to replace the OK Button with a message that clearly show what the Button does. For example, in a "Close without saving?" alert, the OK text could be "Discard changes". A third Button can also be useful (for example, a "Save changes" Button in the previous" case. In all cases a CANCEL Button must be present to let the user cancel the operation.