028.htm

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</span></pre> 
<p><span class="p2">GetVerb的Index参数能得到0，1，2三个可能值，在0时返回‘OnEvent’handler  
code’，在1时返回‘Exeute TxxxDialog’，2时返回其它值）返回‘About’</span></p>  
<pre>
<span class="p2"><b>function</b> TCommonDialogComponentEditor.GetVerb(Index: Integer): string;
<b>begin</b>
<b>case</b> Index <b>of</b>
0: GetVerb := '&amp;OnEvent handler code';
1: GetVerb := '&amp;Execute ' + Component.ClassName + '...';
<b>else</b> GetVerb := '&amp;About...'
<b>end</b>
<b>end</b> <i>{GetVerb}</i>;
</span></pre> 
<p><span class="p2">最后，执行动作。</span></p> 
<pre>
<span class="p2"><b>procedure</b> TCommonDialogComponentEditor.ExecuteVerb(Index: Integer);
<b>begin</b>
<b>if</b> index &gt;= 2 <b>then</b>
MessageDlg('TCommonDialogDefaultEditor (c) 1996 by Dr.Bob',
mtInformation, [mbOk], 0)
<b>else</b>
<b>if</b> index = 1 <b>then</b>
<b>begin</b>
<b>if</b> (Component <b>IS</b> TFindDialog) <b>then</b> <i>{ also TReplaceDialog }</i>
(Component <b>AS</b> TFindDialog).Execute
<b>else</b>
<b>if</b> (Component <b>IS</b> TFontDialog) <b>then</b>
(Component <b>AS</b> TFontDialog).Execute;
Designer.Modified
<b>end</b>
<b>else</b> <b>inherited</b> Edit <i>{ TDefaultEditor.Edit for index = 0 }</i>
<b>end</b> <i>{ExecuteVerb}</i>;
</span></pre> 
<p><span class="p2">我想，你已经明白了。如果安装且激活了新的TCommonDialog  
DefaultEditor ，在TFindDialog 时，可得到如下弹出式菜单：</span></p>  
<p align="center">　</p> 
<p><span class="p2">如果选择第一项，双击控件，这一般是执行菜单动作的第一项），自动地弹到代码编辑器中，一切都如你所愿，代码如下：</span></p> 
<pre>
<span class="p2"><b>unit</b> CompMenu;
<b>interface</b>
<b>uses</b>
DsgnIntf;


<b>Type</b>
TCommonDialogComponentEditor = <b>class</b>(TComponentEditor)
<b>function</b> GetVerbCount: Integer; <b>override</b>;
<b>function</b> GetVerb(index: Integer): String; <b>override</b>;
<b>procedure</b> Executeverb(index: Integer); <b>override</b>;
<b>end</b>;


TCommonDialogDefaultEditor = <b>class</b>(TDefaultEditor)
<b>function</b> GetVerbCount: Integer; <b>override</b>;
<b>function</b> GetVerb(index: Integer): String; <b>override</b>;
<b>procedure</b> Executeverb(index: Integer); <b>override</b>;
<b>end</b>;


<b>procedure</b> Register;


<b>implementation</b>
<b>uses</b>
Dialogs;


<i>{ TCommonDialogComponentEditor }</i>


<b>function</b> TCommonDialogComponentEditor.GetVerbCount: Integer;
<b>begin</b>
GetVerbCount := 2
<b>end</b> <i>{GetVerbCount}</i>;


<b>function</b> TCommonDialogComponentEditor.GetVerb(index : Integer): String;
<b>begin</b>
<b>if</b> Index &gt;= 1 <b>then</b> GetVerb := '&amp;About...'
<b>else</b> GetVerb := '&amp;Execute ' + Component.ClassName + '...'
<b>end</b> <i>{GetVerb}</i>;


<b>procedure</b> TCommonDialogComponentEditor.ExecuteVerb(index: Integer);
<b>begin</b>
<b>if</b> index &gt;= 1 <b>then</b>
MessageDlg('TCommonDialogComponentEditor (c) 1996 by Dr.Bob',
mtInformation, [mbOk], 0)
<b>else</b>
<b>begin</b>
<b>if</b> (Component <b>IS</b> TOpenDialog) <b>then</b> <i>{ also TSaveDialog }</i>
(Component <b>AS</b> TOpenDialog).Execute
<b>else</b>
<b>if</b> (Component <b>IS</b> TPrintDialog) <b>then</b>
(Component <b>AS</b> TPrintDialog).Execute
<b>else</b>
<b>if</b> (Component <b>IS</b> TPrinterSetupDialog) <b>then</b>
(Component <b>AS</b> TPrinterSetupDialog).Execute
<b>else</b>
<b>if</b> (Component <b>IS</b> TColorDialog) <b>then</b>
(Component <b>AS</b> TColorDialog).Execute;
Designer.Modified
<b>end</b>
<b>end</b> <i>{ExecuteVerb}</i>;


<i>{ TCommonDialogDefaultEditor }</i>


<b>function</b> TCommonDialogDefaultEditor.GetVerbCount: Integer;
<b>begin</b>
GetVerbCount := 3
<b>end</b> <i>{GetVerbCount}</i>;


<b>function</b> TCommonDialogDefaultEditor.GetVerb(index : Integer): String;
<b>begin</b>
<b>case</b> Index <b>of</b>
0: GetVerb := '&amp;OnEvent handler code';
1: GetVerb := '&amp;Execute ' + Component.ClassName + '...';
<b>else</b> GetVerb := '&amp;About...'
<b>end</b>
<b>end</b> <i>{GetVerb}</i>;


<b>procedure</b> TCommonDialogDefaultEditor.ExecuteVerb(index: Integer);
<b>begin</b>
<b>if</b> index &gt;= 2 <b>then</b>
MessageDlg('TCommonDialogDefaultEditor (c) 1996 by Dr.Bob',
mtInformation, [mbOk], 0)
<b>else</b>
<b>begin</b>
<b>if</b> (Component <b>IS</b> TFindDialog) <b>then</b> <i>{ also TReplaceDialog }</i>
(Component <b>AS</b> TFindDialog).Execute
<b>else</b>
<b>if</b> (Component <b>IS</b> TFontDialog) <b>then</b>
(Component <b>AS</b> TFontDialog).Execute;
Designer.Modified
<b>end</b>
<b>else inherited</b> Edit <i>{ TDefaultEditor.Edit }</i>
<b>end</b> <i>{ExecuteVerb}</i>;


<b>procedure</b> Register;
<b>begin</b>
<i>{ empty default component editors }</i>
RegisterComponentEditor(TOpenDialog, TCommonDialogComponentEditor);
RegisterComponentEditor(TPrintDialog, TCommonDialogComponentEditor);
RegisterComponentEditor(TPrinterSetupDialog, TCommonDialogComponentEditor);
RegisterComponentEditor(TColorDialog, TCommonDialogComponentEditor);
<i>{ event default component editors }</i>
RegisterComponentEditor(TFontDialog, TCommonDialogDefaultEditor);
RegisterComponentEditor(TFindDialog, TCommonDialogDefaultEditor)
<b>end</b>;
<b>end</b>.
</span></pre> 
<p><span class="p2"><font size="5"><b>结论：<br> 
</b></font>在本文中，我们讨论了如何使用属性编辑器和控件编辑器来扩展和增强Delphi设计环境，我们知道了如何使用已有的编辑器，更重要的是，怎样写自己的，属性编辑器和控件编辑器只是所谓OpenTools  
API  
的头两个，甚至不是最重要的，但是确实是非常有益。从这里开始吧!<br> 
<br> 
<b>Bibliography</b> <br> 
If you want more interesting and technical information on the Open Tools API of Delphi,  
then you should check out my articles in <a style="color: rgb(255,0,128) "  
href="javascript:if(confirm('http://hub.myrice.com/www.itecuk.com/delmag/index.htm  \n\nThis file was not retrieved by Teleport Pro, because it is linked too far away from its Starting Address. If you increase the in-domain depth setting for the Starting Address, this file will be queued for retrieval.  \n\nDo you want to open it from the server?'))window.location='http://hub.myrice.com/www.itecuk.com/delmag/index.htm'" tppabs="http://hub.myrice.com/www.itecuk.com/delmag/index.htm" target="_blank">The Delphi Magazine or the 
book The Revolutionary Guide to Delphi 2</a>, ISBN 1-874416-67-2 published by WROX Press. </span></p>  
<p align="center"><font color="#CC0000" size="1" face="Comic Sans MS">This webpage (<u>c</u>) 
1999 by webmaster drs. Robert E. Swart (aka <a href="mailto:[e-mail]">Dr.Bob</a> - <a 
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