ControlMargins (C++)

Description

This example demostrates the usage of the Margins and AlignWithMargins properties. Note that Margins will only work when AlignWithMargins is set to True and Align is not alNone.

Code

#define TopPanelMargin 10
#define BottomPanelMargin 20

TPanel *TopPanel, *BottomPanel;

__fastcall TForm2::TForm2(TComponent* Owner)
	: TForm(Owner)
{
	/* Create a new panel and align it to top. */
	TopPanel = new TPanel(this);
	TopPanel->Parent = this;
	TopPanel->Align = alTop;
	TopPanel->Height = (ClientHeight / 2);

	/* Create a new panel and align it to the remaining client size. */
	BottomPanel = new TPanel(this);
	BottomPanel->Parent = this;
	BottomPanel->Align = alClient;

	/* Set Top panel margins .*/
	/* Note: Margins will not have an effect if Align is alNone. */
	TopPanel->Margins->SetBounds(TopPanelMargin, TopPanelMargin,
								 TopPanelMargin, TopPanelMargin);
	TopPanel->AlignWithMargins = true;
	TopPanel->Caption = "TopPanel";

	/* Set Top Bottom margins. */
	/* Note: Margins will not have an effect if Align is alNone. */
	BottomPanel->Margins->SetBounds(BottomPanelMargin, BottomPanelMargin,
								   BottomPanelMargin, BottomPanelMargin);
	BottomPanel->AlignWithMargins = true;
	BottomPanel->Caption = "BottomPanel";

	if ((TopPanel->Top != TopPanelMargin) ||
	   (TopPanel->Left != TopPanelMargin) ||
	   (TopPanel->Width != (ClientWidth - (TopPanelMargin * 2))) ||
	   (BottomPanel->Top != (TopPanel->Height + (TopPanelMargin * 2) +
											   BottomPanelMargin)) ||
	   (BottomPanel->Left != BottomPanelMargin) ||
	   (BottomPanel->Width != (ClientWidth - (BottomPanelMargin * 2))))
	   {
		  MessageDlg(String(
			"This should not happen! Position and size are ")+
			"calculated relative to the margins",
			mtError, TMsgDlgButtons() << mbOK, 0);
	   }
}

Uses

• Vcl.Controls.TControl.AlignWithMargins ( fr | de | ja )
• Vcl.Controls.TControl.Margins ( fr | de | ja )
• Vcl.Controls.TMargins ( fr | de | ja )
• Vcl.Controls.TControl.SetBounds ( fr | de | ja )