Window State Components
Information Sheet

Contents

• Overview
• Compatibility
• Installation
• Change log
• License
• About the Author

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Overview

The window state components can save and restore a window's size, position and state (minimized, maximized or normal) between program executions. Two components are provided that use different means of recording the window's information. They are:

• TPJWdwState
  This component records window information in an ini file. The user has control over the ini file name (via the IniFileName property) and the name of the section of the file where window information is recorded (using the Section property). Alternatively the ini and section names can be configured by handling the OnGetIniData event that is triggered immediately before the ini file is read or written.
• TPJRegWdwState
  This component uses the registry to record window information. The registry root key and sub key where the information is stored are controlled by the RootKey and SubKey properties, or by handling the OnGetRegData event. This event is triggered just before the registry is accessed.

Both components implement the same functionality, controlled by some common properties and events, as follows:

• The components can automatically restore and save windows when the program starts up and closes down (using the AutoSaveRestore property). If AutoSaveRestore is set to False then the Restore and Save methods must be called from the host application.
• The OnReadWdwState event can be handled in order to change the stored window's state, size and position values before the window is restored. This event is called after reading the data and before sizing the window.
• The Options property can be used to customise the way the window is restored as follows:
  • The components can be instructed to ignore the saved window state – the window is then displayed in the normal state.
  • The window's saved size can be ignored and the default size of the form used instead. This is useful for dialog boxes and fixed size windows.
  • The window can be kept within the current work area of the desktop.
• When the form is to be restored in a minimized state it briefly appears on screen in the normal state before being minimized. The MinimizeDelay property controls the delay between the window appearing and being minimized.

Other features include:

• A help file that integrates into the Delphi 3 to 7 IDE. The help file does not integrate with Delphi 2005 and later but can be used, with some loss of functionality, independently of the IDE.
• A property editor is provided for editing the RootKey property TPJRegWdwState). This editor is also available separately.

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Compatibility

The Window State Components compile with Delphi 3 and later. They have been tested with Delphi 3, 4, 6, 7 and 2006. The property editor can be used with any of the compilers supported by the components.

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Installation

The Window State Components, their documentation and demo programs are supplied in a zip file. Before installing you need to extract all the files from the zip file, preserving the directory structure. The following files will be extracted:

• PJWdwState.pas – component source code.
• PJWdwState.dcr – resource file containing component palette glyphs.
• PJWdwState.hlp – component help file that integrates with the Delphi 3 to 7 OpenHelp system.
• PJWdwState.als – a-link keyword file for integration with the Delphi 6 or 7 OpenHelp system.
• PJHKEYPropEdit.pas – HKEY property editor.
• ReadMe.htm – this file.
• ChangeLog.txt – component's change log.
• Demos\DemoReadMe.htm – read me file explianing use of demo programs.
• Demos\WdwStateDemos.bpg – demo project group file.
• Demos\1\StandardDemo.dpr – demo 1 project file.
• Demos\1\StandardDemo.res – icon resource for demo 1.
• Demos\1\FmDemo.pas/.dfm – 1st demo's main window form and source.
• Demos\1\FmDemoDlg.pas/.dfm – 1st demo's modal dialog form and source.
• Demos\2\StandAloneDemo.dpr – demo 2 project file.
• Demos\2\StandAloneDemo.res – icon resource for demo 2.
• Demos\2\FmMain.pas/.dfm – 2nd demo's main window form and source.

You can now proceed to install the components and property editor using the emphasised files above. Installation methods vary between Delphi versions, so follow the instructions that apply to your version below. Note that $(DELPHI) represents the path where the appropriate version of Delphi was installed. Similarly $(BDS) refers to the installation path of a version of the Borland Development System.

• Installation with Delphi 2005 & 2006
• Installation with Delphi 3 to 7

Installation with Delphi 2005 & 2006

The components must be installed into a Delphi Win32 design package. It is assumed that you will be installing into an existing package. You may decide to install into the "user" package: $(BDS)\Lib\dclusr.dpk.

1. Decide upon a suitable location into which to install the components. This may be a subdirectory of your Borland Studio Projects or $(BDS)\lib folders.
2. Copy PJWdwState.pas and PJWdwState.dcr to the chosen installation folder. If you wish to also install the HKEY property editor for use with TPJRegWdwState you should copy PJHKEYPropEdit.pas to the same location.
3. Start the Development System (selecting the Delphi Win32 personality if appropriate) then:
   • Open the required package. Select File | Open menu and choose a suitable package source file.
   • The package will now be displayed in the Project Manager with a .bpl extension. Right click the package's entry and select Add to display the Add dialog box. Enter the full path to PJWdwState.pas in the Unit file name edit box (use the Browse button to navigate to the file). Click OK to add the component to the package.
   • If required repeat the previous step for PJHKEYPropEdit.pas.
   • Back in the Project Manager, check that PJWdwState.pas and PJWdwState.dcr and, if appropriate, PJHKEYPropEdit.pas, appear under the package's Contains node. If so, right click the package's entry again and select Compile. If the resulting compilation succeeds a message should be displayed confirming that TPJWdwState and TPJRegWdwState have been registered. The components should now appear in the "DelphiDabbler" section of the Tool Palette. (Note this will only appear when a form is selected in the designer). If you have installed PJHKEYPropEdit.pas the property editor will be used by the Object Inspector when a property of type HKEY is selected.
   • If the components do not appear the package may not have been installed. Install it from the Project Manager by selecting the package's Install right click menu option.
   • Close the package project using the File | Close menu item. Accept any prompt that offers to save the package project.
4. If you wish you can now delete PJWdwState.pas and, if used, PJHKEYPropEdit.pas, from the chosen installation folder.
5. The supplied help file cannot be integrated with the IDE's help system. However it can be used independently of the IDE, albeit with reduced functionality.
6. The demo programs can be loaded into Delphi and compiled and run as required.

Installation with Delphi 3 to 7

The components must be installed into a design package. It is assumed that you will be installing into an existing package. You may wish to use the "user" package named dclusr.dpk or dclusrXX.dpk (where XX is a version number). This package can be found in $(DELPHI)\Lib.

1. Decide upon a suitable location into which to install the components. This may be a subdirectory of your $(DELPHI)\lib folder.
2. Copy PJWdwState.pas and PJWdwState.dcr to the chosen installation folder. If you wish to also install the HKEY property editor for use with TPJRegWdwState you should copy PJHKEYPropEdit.pas to the same location.
3. Start Delphi then:
   • Choose the Component | Install Component menu option to display the Install Component dialog box. Ensure the Into existing package tab is selected. Enter the full path to PJWdwState.pas in the Unit file name edit box (use the adjacent Browse button to navigate to the file). If required, repeat the previous step for PJHKEYPropEdit.pas. Choose the required package from the Package description combo box, or by navigating to the package using Browse. Click OK to confirm your selections.
   • A confirmation dialog box may displayed, querying whether it is OK to rebuild and reinstall the package. Click Yes to proceed.
   • The package will now be built and a dialog box should be displayed stating that the TPJWdwState and TPJRegWdwState components have been installed. Click OK to dismiss the dialog box.
   • The components will appear on the "DelphiDabbler" palette. If you have installed PJHKEYPropEdit.pas the property editor will be used by the Object Inspector when a property of type HKEY is selected.
4. If you wish you can now delete PJWdwState.pas and, if used, PJHKEYPropEdit.pas, from the chosen installation folder.
5. The provided help file can be integrated with the IDE's OpenHelp system. Delphi 6 and 7 also require the use of the supplied .als file. The simplest way to install help is to use my Component Help Installer Expert (v2.2.1 or later). If you prefer to install manually, this article explains the process.
6. The demo program can be loaded into Delphi and compiled and run as required. Please note that the first demo does not compile or run with Delphi 3.

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Change log

A complete change log is provided in a text file that is included in the download.

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License

This source code is subject to the Mozilla Public License Version 1.1 (the "License"); you may not use this program except in compliance with the License. You may obtain a copy of the License at http://www.mozilla.org/MPL/.

Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language governing rights and limitations under the License.

The Original Code is Window State Components.

The Initial Developer of the Original Code is Peter Johnson (http://www.delphidabbler.com/).

Portions created by the Initial Developer are Copyright © 1999-2005 Peter Johnson. All Rights Reserved.

Contributor(s):

All relevant trademarks are acknowledged.

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About the Author

I'm Peter Johnson – a hobbyist programmer living in Ceredigion in West Wales, UK, writing write mainly in Delphi. My programs are available for download from: http://www.delphidabbler.com/.