TPanel.ClientHeight property

Member of TPanelpublishedIn unit ExtCtrls

The height for the client area on the control.

Declaration

pascal

property ClientHeight:;

Description

ClientHeight is an Integer property with the number of pixels needed for the vertical client area on the control. The property contains the value from the Bottom member in ClientRect. Changing the value for ClientHeight causes SetClientSize to be called to apply the existing ClientWidth and the new value for the property.

The value for ClientHeight is not stored or used to set the Height for the control during LCL component streaming. It is used, however, when AutoSizing is restored and when auto-layout policies using Anchors are applied to the control. For example, when Anchors is set to [akBottom] the value in ClientHeight is needed / used.

In the LCL, ClientHeight has the same value as Height. Derived classes (like TCustomForm or TForm) may implement a ClientHeight property that differs from Height - but in the current LCL version, they do not. This differs from the behavior in the Delphi VCL where a TForm instance adjusts the value in ClientHeight to remove pixels used in non-client areas like the title bar, borders, frames, and scroll bars. LCL uses this approach because there is no reliable way to determine the sizes for all of the non-client areas on all of the platforms where LCL is supported. Without a reliable way, the LCL would needlessly move the forms around on the screen or resize them endlessly. In the LCL, neither Height nor ClientHeight include the non-client area on a form instance. The height of a TMainMenu instance is omitted from both values as well.

Use ClientWidth to access the number of pixels needed for the horizontal client area on the control.

This description is the one of Controls.TControl.ClientHeight.

TPanel.ClientHeight property

Declaration

Description

See also