TScrollingWinControl class

In unit Forms

Implements a windowed control with scroll bars.

Declaration

pascal

TScrollingWinControl = class(TCustomControl)

Inheritance

TScrollingWinControl
TCustomControl
TWinControl
TControl
TLCLComponent
TComponent

Descends from it: TCustomDesignControl TScrollBox

Description

This class introduces a logical (virtual) client area, part of which is visible in the physical (visible) client area. ScrollBars allow the user to scroll through the logical client area.

TScrollingWinControl is the ancestor for components like TScrollBox and TCustomDesignControl, and indirectly for TCustomFrame and TCustomForm.

Properties

`AutoScroll`	protected	Indicates whether scroll bars are automatically displayed or hidden when needed.
`HorzScrollBar`	published	The horizontal scroll bar for the control.
`VertScrollBar`	published	The vertical scroll bar for the control.

Methods

`WSRegisterClass`	protected	Registers the class instance for use in the widgetset.
`AlignControls`	protected	Aligns the controls which have the class instance as their Parent.
`AutoScrollEnabled`	protected	Indicates if automatic scrolling is enabled for the control.
`CalculateAutoRanges`	protected	Sets or resets the ranges used for scroll bars on the control.
`CreateWnd`	protected	Creates the window handle for the control.
`DestroyWnd`	protected	Frees or invalidates resources in the class instance when the window Handle is freed.
`GetClientScrollOffset`	protected	The origin for the physical client area.
`GetLogicalClientRect`	protected	Returns the logical size of the client area on the control.
`DoOnResize`	protected	Performs actions needed when the control has been resized.
`GetPreferredSizeClientFrame`	protected	Calculates the size of the client area for the control excluding visible scroll bars.
`WMSize`	protected	Performs actions needed to handle WMSize messages.
`WMHScroll`	protected	Delegates scroll messages to the handler for the horizontal scroll bar.
`WMVScroll`	protected	Delegates scroll messages to the handler for the vertical scroll bar.
`ComputeScrollbars`	protected	Updates Page, AutoRange, IsScrollBarVisible, and returns True when changed.
`SetAutoScroll`	protected	Sets the value for the AutoScroll property.
`Loaded`	protected	Performs actions when the component has been loaded from the LCL streaming mechanism.
`Resizing`	protected	Performs actions needed when the control processes the WMSize message.
`SetAutoSize`	protected	Sets the value for the AutoSize property.
`Create`	public	Constructor for the class instance.
`Destroy`	public	Destructor for the class instance.
`ScreenToClient`	public	Converts the specified screen coordinates to client-relative coordinates.
`ClientToScreen`	public	Converts the specified client coordinates to absolute screen coordinates.
`UpdateScrollbars`	public	Initializes or updates the scroll bars for the control.
`GetControlClassDefaultSize`	public	Returns the default dimensions for new instances of the class.
`ScrollBy`	public	Tells the widget to scroll the client area by the specified relative values.
`ScrollInView`	public	Aligns the specified control to its parent and scrolls it into view.