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WindowsDragSourceMBS class

Type Topic Plugin Version macOS Windows Linux Console & Web iOS
class Drag & Drop MBS Win Plugin 10.5 No Yes No Yes, Windows only No
Function: The class for Drag and Drop on Windows to create a drag source.
Notes:
The WindowsDragSourceMBS class is one of the class you implement to provide drag-and-drop operations in your application. It contains methods used in any application used as a data source in a drag-and-drop operation. The data source application in a drag-and-drop operation is responsible for:

  • Determining the data being dragged based on the user's selection.
  • Initiating the drag-and-drop operation based on the user's mouse actions.
  • Generating some of the visual feedback during the drag-and-drop operation, such as setting the cursor and highlighting the data selected for the drag-and-drop operation.
  • Canceling or completing the drag-and-drop operation based on the user's mouse actions.
  • Performing any action on the original data caused by the drop operation, such as deleting the data on a drag move.

WindowsDragSourceMBS contains the events for generating visual feedback to the end user and for canceling or completing the drag-and-drop operation.

When To Implement

Implement WindowsDragSourceMBS if you are developing a container or server application that can act as a data source for a drag-and-drop operation. The WindowsDragSourceMBS interface is only required during the drag-and-drop operation.

If you implement the WindowsDragSourceMBS class, you must also implement the DataObjectMBS class on the same object to represent the data being transferred.

You can use the same implementation of DataObjectMBS for drag-and-drop data as for the data object offered to the clipboard. After you have implemented clipboard operations in your application, you can add drag-and-drop operations with only a little extra work.

When To Use

You do not usually call the WindowsDragSourceMBS methods directly. Instead, your data source calls the DoDragDrop function when it detects that the user has initiated a drag-and-drop operation. Then, DoDragDrop calls the WindowsDragSourceMBS methods during the drag-and-drop operation.

For example, DoDragDrop calls WindowsDragSourceMBS.GiveFeedback when you need to change the cursor shape or when you need to provide some other visual feedback. DoDragDrop calls WindowsDragSourceMBS.QueryContinueDrag when there is a change in the mouse button state to determine if the drag-and-drop operation was canceled or completed.

While the drag classes compile for Web Edition, they run on the server, so they have no effect on the client browser!

Feedback, Comments & Corrections

This class has no sub classes.

Some examples which use this class:


The items on this page are in the following plugins: MBS Win Plugin.


WindowsDNSRecordTXTMBS   -   WindowsDriveNotificationMBS




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