[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'Controls' (#lcl)

TDragImageList

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

A list of Images used during Drag operations.

Declaration

Source position: controls.pp line 383

type TDragImageList = class(TCustomImageList)

protected

  function GetResolutionClass; override;

  procedure Initialize; override;

  

initializes the cursor shape and image index for the list.

public

  function BeginDrag();

  

Start dragging an image; returns True if successful.

  function DragLock();

  

Show drag image during drag operation.

  function DragMove();

  

Shows the drag image at a new location.

  procedure DragUnlock;

  

Hide the drag image.

  function EndDrag;

  

Finish dragging of the image, restore the old cursor shape.

  procedure HideDragImage;

  

Hides the drag image without unlocking the window.

  function SetDragImage();

  

Set index of dragged image and hotspot.

  procedure ShowDragImage;

  

Displays the drag image.

  property DragCursor: TCursor; [rw]

  

The cursor shape to use while dragging.

  property DragHotspot: TPoint; [rw]

  

The position of the HotSpot image, i.e. the offset to the mouse position while dragging.

  property Dragging: Boolean; [r]

  

True if dragging in progress.

  property DraggingResolution: TDragImageListResolution; [r]

  

Gets the scaled image resolution with the drag images for the list.

  property Resolution []: TDragImageListResolution; [r]

  

Gets the image resolution for the specified image width.

end;

Inheritance

TDragImageList

  

A list of Images used during Drag operations.

|

TCustomImageList

  

The base class for TImageList.

|

TLCLComponent

  

The base class for LCL components which have an associated widget.

|

TComponent

?

TObject

Description

A drag image is shown when a DragImageList is supplied at all, and when no accepting target is under the mouse, or the source control style includes csDisplayDragImage, or AlwaysShowDragImage is set in the DragObject.

In drag-dock operations typically no drag image is shown, since the DockRect frame already gives all required visual feedback.

This is a general overview of the usage of this class: