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

TUpDown

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

TUpDown - a pair of arrow-like buttons which are used to increment or decrement some controlled variable; often attached to a scroll-bar but can also control a digital numeric display

Declaration

Source position: comctrls.pp line 1925

type TUpDown = class(TCustomUpDown) end;

published

  property Align: TAlign;

  property AlignButton: TUDAlignButton;

  

AlignButton - how to align the button: left or right

  property Anchors: TAnchors;

  

The set of anchor definitions for this control.

  property ArrowKeys: Boolean;

  

ArrowKeys - if True, the control can be operated by the keyboard's arrow keys which would simulate a click on the Next or Previous button

  property Associate: TWinControl;

  

Associate - the associated control whose properties (controlled variable) are to be changed by the UpDown control

  property BorderSpacing: TControlBorderSpacing;

  

Determines the inner and outer border spacing for this control.

  property Color: TColor;

  property Constraints: TSizeConstraints;

  

The minimal and maximal Width and Height of this control.

  property Enabled: Boolean;

  

Determines whether the control reacts on mouse or keyboard input.

  property Hint: TTranslateString;

  

The text to show in the Hint window for this control.

  property Increment: Integer;

  

The amount by which the controlled variable is to be increased or decreased on each click

  property Max: SmallInt;

  

Max - greatest value of controlled variable

  property Min: SmallInt;

  

Min - least value of controlled variable

  property MinRepeatInterval: Byte;

  property OnChanging: TUDChangingEvent;

  

OnChanging - event handler for a change in the value of the controlled variable

  property OnChangingEx: TUDChangingEventEx;

  property OnClick: TUDClickEvent;

  

OnClick - special event handler for a click on up or down button

  property OnContextPopup: TContextPopupEvent;

  

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

  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 OnMouseDown: TMouseEvent;

  

Event handler for mouse button going down.

  property OnMouseEnter: TNotifyEvent;

  property OnMouseLeave: TNotifyEvent;

  property OnMouseMove: TMouseMoveEvent;

  

Event handler for mouse movement within the control.

  property OnMouseUp: TMouseEvent;

  

Event handler for mouse button going up.

  property OnMouseWheel: TMouseWheelEvent;

  property OnMouseWheelDown: TMouseWheelUpDownEvent;

  property OnMouseWheelUp: TMouseWheelUpDownEvent;

  property Orientation: TUDOrientation;

  

Whether horizontal or vertical

  property ParentColor: Boolean;

  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 Position: SmallInt;

  

The Position of the UpDown control

  property ShowHint: Boolean;

  

Enables the Hint display.

  property TabOrder: TTabOrder;

  

Determines the sequence of controls, reachable when the user presses the Tab key.

  property TabStop: Boolean;

  

Allows the user to navigate to this control, by pressing the Tab key.

  property Thousands: Boolean;

  

If True, multiply all displayed values and the Increment by 1000

  property Flat: Boolean;

  property Visible: Boolean;

  

Allows to show or hide the control, and all of its children.

  property Wrap: Boolean;

  

If True, displayed control or value starts again from minimum or maximum value if clicking a button would cause incrementing or decrmenting beyond the extreme value

Inheritance

TUpDown

  

TUpDown - a pair of arrow-like buttons which are used to increment or decrement some controlled variable; often attached to a scroll-bar but can also control a digital numeric display

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TCustomUpDown

  

TCustomUpDown - base class for TUpDown - a pair of arrow-like buttons which are used to increment or decrement some controlled variable; often attached to a scroll-bar but can also control a digital numeric display

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TCustomControl

  

The base class for windowed controls which paint themselves.

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TWinControl

  

The base class for controls which can contain other (child) controls.

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TControl

  

The base class for visible controls.

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TLCLComponent

  

The base class for LCL components associated with widgets.

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TComponent

?

TObject

Description

TUpDown - a pair of arrow-like buttons which are used to increment or decrement some controlled variable; often attached to a scroll-bar but can also control a digital numeric display

The control definition itself does not specify the variable upon which the buttons operate. The application programmer is responsible for supplying an event handler for OnClick to determine which button has been selected (designated btNext or btPrev) and incrementing or decrementing the variable in the control with which the UpDown is associated.

The amount by which the variable is changed is set by the integer property Increment with the optional multiplier Thousands (a boolean property).

For example the UpDown control may be used to move a slider up and down a scale by a specified amount for each click; alternatively a number may be displayed in a text box and clicking the buttons of the UpDown control may increment or decrement the number displayed by a specified amount.

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