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

TDragManager

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

The abstract base class for managing the dragging of controls (to be dropped or docked).

Declaration

Source position: controls.pp line 523

type TDragManager = class(TComponent) end;

protected

  procedure KeyUp(); virtual; abstract;

  

Handler for keyboard key released.

  procedure KeyDown(); virtual; abstract;

  

Handler for keyboard key pressed.

  procedure CaptureChanged(); virtual; abstract;

  

Aborts the dragging operation, when the capturing control really has changed.

  procedure MouseMove(); virtual; abstract;

  

Generates the visual feedback when the mouse moves.

  procedure MouseUp(); virtual; abstract;

  

Ends dragging.

  procedure MouseDown(); virtual; abstract;

  

Nop.

public

  constructor Create(); override;

  

Initializes the Delphi default dragging parameters.

  function IsDragging; virtual; abstract;

  

Check if dragging is in progress.

  function Dragging(); virtual; abstract;

  

True if the specified control is being dragged.

  procedure RegisterDockSite(); virtual; abstract;

  

Adds the control to the list of registered docking sites.

  procedure DragStart(); virtual; abstract;

  

Starts dragging a control.

  procedure DragMove(); virtual; abstract;

  

Updates the visual dragging feedback.

  procedure DragStop(); virtual; abstract;

  

Ends dragging.

  property DragImmediate: Boolean; [rw]

  

Start dragging immediately, on MouseDown?

  property DragThreshold: Integer; [rw]

  

The threshold amount by which the mouse must move before delayed dragging starts. (default 5 pixels)

Inheritance

TDragManager

  

The abstract base class for managing the dragging of controls (to be dropped or docked).

|

TComponent

?

TObject

Description

This is the OO version of the Delphi drag manager, implemented in TDragManagerDefault.

Remark: The registered dock sites should be stored in a persistent list, not in a DragManager instance.

[entire review DoDi 2010-02-16]

The latest version of this document can be found at lazarus-ccr.sourceforge.net.