Resizable dialogs, form views and property sheets for WTL

• Download demo project - 10 Kb
• Download source - 180 Kb

Introduction

• Form views
• Dialogs
• Property Sheet and property pages

How to use the classes in your WTL application

Resizeable form views

• Include the file LayoutMgr.h in the header file of your dialog class and add the file LayoutMgr.cpp to your project.
• Derive your form view class from CResizableFormViewImpl instead of CDialogImpl.
• Add the message map of CResizableFormViewImpl before your own message handlers.
• Override the DefineLayout method in order to set the layout constraints.
• Define the array _controlsToClip which defines the controls which should be clipped when painting the dialog.

class MyFormView : public CResizableFormViewImpl<MyFormView>
{
public:
	typedef CResizableFormViewImpl<MyFormView> dlgBase;
	...
	BEGIN_MSG_MAP(MyFormView)
		CHAIN_MSG_MAP(dlgBase)
		...
	END_MSG_MAP()
	...
	virtual void DefineLayout();
	static const UINT _controlsToClip[];
};	

Resizeable dialogs

class MyDialog : public CResizableDialogImpl<MyDialog>
{
public:
	typedef CResizableDialogImpl<MyDialog> dlgBase;
	...
	BEGIN_MSG_MAP(MyDialog)
		CHAIN_MSG_MAP(dlgBase)
		...
	END_MSG_MAP()
	...
	virtual void DefineLayout();
	static const UINT _controlsToClip[];
};	

Resizeable property sheet

• Include the file LayoutMgr.h in the header files of your property sheet and property pages classes and add the file LayoutMgr.cpp to your project.
• For the property sheet:
  • If you want to use your property sheet:
    • as a popup window:
      • Derive your property sheet class from CPopupResizablePropertySheetImpl instead of CPropertySheetImpl.
      • In the call to CPopupResizablePropertySheetImpl constructor, you can change the value of the flag useHandle. If this flag is set to true (default value), a sizing gripper is displayed in the lower right corner of the property sheet.
    • as a child window:
      • Derive your property sheet from CChildResizablePropertySheetImpl instead of CPropertySheetImpl.
      • Pass the ID of the control which will serve as a place holder for the property sheet to the call of the constructor of CChildResizablePropertySheetImpl.
      • Call the method Create in the parent window for creating the property sheet.
  • Add the message map of CPopupResizablePropertySheetImpl or CChildResizablePropertySheetImpl before your own message handlers.
• For the property pages:
  • Derive your property page class from CResizablePropertyPageImpl instead of CPropertyPageImpl.
  • Override the DefineLayout method in order to set the layout constraints.
  • Define the array _controlsToClip which defines the controls which should be clipped when painting the dialog.
• Property sheets don't receive any WM_INITDIALOG message. If you want to do something just after the initialisation of the property sheet, you can override the method OnInitDialog.

class MyPropertySheet : public CPopupResizablePropertySheetImpl<MyPropertySheet>
{
public:
	typedef CPopupResizablePropertySheetImpl<MyPropertySheet> dlgBase;
	...
	BEGIN_MSG_MAP(MyPropertySheet)
		CHAIN_MSG_MAP(dlgBase)
		...
	END_MSG_MAP()
	...
};	

class MyPropertyPage : public CResizablePropertyPageImpl<MyPropertyPage>
{
public:
	typedef CResizablePropertyPageImpl<MyPropertyPage> dlgBase;
	...
	BEGIN_MSG_MAP(MyPropertyPage)
		CHAIN_MSG_MAP(dlgBase)
		...
	END_MSG_MAP()
	...
	virtual void DefineLayout();
	static const UINT _controlsToClip[];
};	

Setting the layout constraints

In order to layout the children when the dialog is resized, you must override the DefineLayout method. This method is called during the initialisation of the dialog and allow to define the geometrical relationships between the child window which will alow to move and resize them in the desired way.

The way of setting layout constraints is inspired by the methods of the XmForm widget of Motif (quite old stuff... ). It's a little tedious, but very simple and efficient.

Constraints are defined by attaching the sides of a child window to the side of another child window or to one of the side of the parent window.

• By default all the sides of a child window are without any constraint (method AttachNone). It means that when the dialog is resized, the child window is neither resized nor moved:

  

• A side of a child window can be attach to the same side of the parent window (method AttachForm). For example the following code:

  	AttachForm(IDC_1, ATTACH_RIGHT);
  

  will have the following effect:

  

  And the following code:

  	AttachForm(IDC_1, ATTACH_LEFT);
  	AttachForm(IDC_1, ATTACH_RIGHT);
  

  will have the following effect:

  

  The horizontal or the vertical center of the child window can be attached to the parent window. For example the following code:

  	AttachForm(IDC_1, ATTACH_HCENTER);
  

  will have the following effect:

  

• A side of a child window can be attach to the opposite side of the parent window (method AttachOppositeForm). For example the following code:

  	AttachOppositeForm(IDC_1, ATTACH_LEFT);
  

  will have the following effect:

  

• A side of a child window can be attach to the opposite side of another child window (method AttachWidget). For example the following code:

  	AttachForm(IDC_1, ATTACH_HCENTER);
  	AttachWidget(IDC_2, ATTACH_LEFT, IDC_1);
  

  will have the following effect:

  

• A side of a child window can be attach to the same side of another child window (method AttachOppositeWidget). For example the following code:

  	AttachForm(IDC_1, ATTACH_LEFT);
  	AttachForm(IDC_1, ATTACH_RIGHT);
  	AttachOppositeWidget(IDC_2, ATTACH_LEFT, IDC_1);
  	AttachOppositeWidget(IDC_2, ATTACH_RIGHT, IDC_1);
  

  will have the following effect:

  

  The horizontal or the vertical center of the child window can be attached to the same side of another child window. For example the following code:

  	AttachForm(IDC_1, ATTACH_LEFT);
  	AttachForm(IDC_1, ATTACH_RIGHT);
  	AttachOppositeWidget(IDC_2, ATTACH_HCENTER, IDC_1);
  

  will have the following effect:

  

A side of a child window can be attach to an invisible grid which is resized with the parent window (method AttachPosition). For example the following code:

	SetNPositions(3);
	AttachPosition(IDC_1, ATTACH_LEFT, 0);
	AttachPosition(IDC_1, ATTACH_RIGHT, 1);
	AttachPosition(IDC_2, ATTACH_LEFT, 1);
	AttachPosition(IDC_2, ATTACH_RIGHT, 2);
	AttachPosition(IDC_3, ATTACH_LEFT, 2);
	AttachPosition(IDC_3, ATTACH_RIGHT, 3);

will have the following effect:

Avoiding screen flickering

class MyDialog : public CResizableDialogImpl<MyDialog>
{
	...
	static const UINT _controlsToClip[];
};	

const UINT MyDialog::_controlsToClip[] = 
{
	IDC_IMG,
	IDOK,
	...
	0
};

Latest Updates

• 9th July 2002
  • Fixed some class name clashes appearing when using WTL7 & ATL7
  • Replaced the SizeGrip window by a standard scrollbar as suggested by Daniel Bowen
  • Added the Unattach methods for removing a control from the list of windows managed by the layout manager
  • Added a maximum size. The maximum size information is only used if _maxWindowSize.cx or _maxWindowSize.cy is greater than 0
  • Implements a workaround an ATL7 bug which prevents ActiveX controls to be initialised in CAxPropertySheetImpl
  • Disabled the clipping code when working with Windows XP
• 7th September 2001
  • Added support for hosting ActiveX controls.
  • Changed the user messages from arbitrary constants to registered messages
• 22nd May 2001
  • Fixed the way minimum sizes and scrollbars are handled in FormViews

Serge .