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

TButton

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

Implements a push button control.

Declaration

Source position: stdctrls.pp line 1267

type TButton = class(TCustomButton)

published

  property Action: TBasicAction;

  

The Action associated with the control.

  property Align: TAlign;

  

Specifies the placement of the control on its Parent control.

  property Anchors: TAnchors;

  

The set of anchor definitions for this control.

  property AutoSize: Boolean;

  

Allows automatic adjustment of the size for the control, according to its content.

  property BidiMode: TBiDiMode;

  

Customization (of text controls) in bidirectional reading environments.

  property BorderSpacing: TControlBorderSpacing;

  

Determines the inner and outer border spacing for this control.

  property Cancel: Boolean;

  

True if the button is the modal Cancel button.

  property Caption: TCaption;

  

The text displayed for the control.

  property Color: TColor;

  

Color used for the button face.

  property Constraints: TSizeConstraints;

  

Contains the minimum and maximum Width and Height for the control.

  property Default: Boolean;

  

True if the button is the default button in a modal form.

  property DoubleBuffered: Boolean;

  

Allows to reduce flicker in the painting of the control.

  property DragCursor: TCursor;

  

The cursor shape shown while the control is dragged.

  property DragKind: TDragKind;

  

The operation when the control is dragged - Drag or Dock.

  property DragMode: TDragMode;

  

Allows the user to drag the control.

  property Enabled: Boolean;

  

Determines whether the control reacts on mouse or keyboard input.

  property Font: TFont;

  

The font to be used for text display in this control.

  property ParentBidiMode: Boolean;

  

Indicates whether the BiDiMode settings in the Parent control are used.

  property ModalResult: TModalResult;

  

Value returned when the control is clicked in a modal form.

  property OnChangeBounds: TNotifyEvent;

  

Event handler signalled when the Bounds of the control have been changed.

  property OnClick: TNotifyEvent;

  

Notification handler for mouse clicks.

  property OnContextPopup: TContextPopupEvent;

  

Invoked when a context-sensitive pop-up menu is requested.

  property OnDragDrop: TDragDropEvent;

  

This handler determines the action on an drop onto this control, in a drag-drop operation.

  property OnDragOver: TDragOverEvent;

  

Event handler for a control being dragged over this control.

  property OnEndDrag: TEndDragEvent;

  

Notification handler for the end of a drag operation.

  property OnEnter: TNotifyEvent;

  

Handler for control receiving the focus.

  property OnExit: TNotifyEvent;

  

Handler for control loosing the focus; This is a good place for checking the finished user input.

  property OnKeyDown: TKeyEvent;

  

Handler for keyboard key pressed.

  property OnKeyPress: TKeyPressEvent;

  

Handler for a character entered by the user.

  property OnKeyUp: TKeyEvent;

  

Event handler signalled when a key up event has occurred for the control.

  property OnMouseDown: TMouseEvent;

  

Event handler signalled when a mouse down event is handled for the control.

  property OnMouseEnter: TNotifyEvent;

  

Event handler signalled when the mouse pointer has entered the control.

  property OnMouseLeave: TNotifyEvent;

  

Event handler signalled when the mouse pointer has left the control.

  property OnMouseMove: TMouseMoveEvent;

  

Event handler for mouse movement within the control.

  property OnMouseUp: TMouseEvent;

  

Event handler signalled when a mouse up event is handled for the control.

  property OnMouseWheel: TMouseWheelEvent;

  

Event handler for mouse wheel turned.

  property OnMouseWheelDown: TMouseWheelUpDownEvent;

  

Event handler for downward movement of mouse wheel.

  property OnMouseWheelUp: TMouseWheelUpDownEvent;

  

Event handler for upward movement of the mouse wheel.

  property OnResize: TNotifyEvent;

  

Notification handler for a resize of the control.

  property OnStartDrag: TStartDragEvent;

  

Event handler for the start of a dragging operation.

  property OnUTF8KeyPress: TUTF8KeyPressEvent;

  

Handler for a character entered by the user.

  property ParentDoubleBuffered: Boolean;

  

Value for the DoubleBuffered property in a Parent control.

  property ParentFont: Boolean;

  

If True, the Font of the control will be the same as the one from the Parent. Default is True.

  property ParentShowHint: Boolean;

  

If True, the value of ShowHint for the control will be the same as the one from the Parent. Default is True.

  property PopupMenu: TPopupMenu;

  

A context-sensitive menu that pops up when the right mouse button is clicked over this control.

  property ShowHint: Boolean;

  

Enables Hint display for the control.

  property TabOrder: TTabOrder;

  

Indicates the navigation order for the control when the user presses the Tab or Shift+Tab key.

  property TabStop: Boolean;

  

Enables navigation using the Tab key.

  property Visible: Boolean;

  

Allows the control, and all of its children, to be displayed or hidden.

end;

Inheritance

TButton

  

Implements a push button control.

|

TCustomButton

  

The base class for a push button control.

|

TButtonControl

  

Specifies a base class for button controls.

|

TWinControl

  

Implements a windowed control which can contain other child controls.

|

TControl

  

The base class for visible controls.

|

TLCLComponent

  

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

|

TComponent

?

TObject

Description

TButton is a TCustomButton descendant which implements a push button control. TButton is used to perform an action when the control is clicked. An OnClick event handler is provided to perform actions needed when the push button is clicked. TButton provides support for the TBasicAction class defined in the FPC Run-time Library (RTL).

Properties are provided to control the appearance and behavior for the control. This includes whether it is the Default or Cancel button on a modal form, and the modal result returned when the push button is clicked.

The control displays a text-based caption and is drawn using a style appropriate for the platform or widgetset. An accelerator key can be defined in the caption which simulates clicking on the push button when the shortcut key is pressed.

Please note that the Caption in the control is always centered. The values in properties like BiDiMode and UseRightToLeftAlignment are ignored in the control.

Please note that the Color for the control defaults to the system-defined color used for button controls.

TButton sets the visibility for properties defined in the ancestor class, and does not introduce any new methods.

Use TBitBtn for a push button control which displays a bitmap instead of a text-based caption.

Use TSpeedButton for a push button control which can remain in the pressed or down state.

See also

TCustomButton

  

The base class for a push button control.