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diff --git a/doc/html/motif-walkthrough-8.html b/doc/html/motif-walkthrough-8.html deleted file mode 100644 index 15c54a2b1..000000000 --- a/doc/html/motif-walkthrough-8.html +++ /dev/null @@ -1,212 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/extensions/motif/doc/walkthrough.doc:1190 --> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> -<title>Replacing the View Widget</title> -<style type="text/css"><!-- -fn { margin-left: 1cm; text-indent: -1cm; } -a:link { color: #004faf; text-decoration: none } -a:visited { color: #672967; text-decoration: none } -body { background: #ffffff; color: black; } ---></style> -</head> -<body> - -<table border="0" cellpadding="0" cellspacing="0" width="100%"> -<tr bgcolor="#E5E5E5"> -<td valign=center> - <a href="index.html"> -<font color="#004faf">Home</font></a> - | <a href="classes.html"> -<font color="#004faf">All Classes</font></a> - | <a href="mainclasses.html"> -<font color="#004faf">Main Classes</font></a> - | <a href="annotated.html"> -<font color="#004faf">Annotated</font></a> - | <a href="groups.html"> -<font color="#004faf">Grouped Classes</font></a> - | <a href="functions.html"> -<font color="#004faf">Functions</font></a> -</td> -<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Replacing the View Widget</h1> - - - -[ <a href="motif-walkthrough-7.html">Previous: Refactoring Existing Code</a> ] -[ <a href="motif-walkthrough.html">Home</a> ] -[ <a href="motif-walkthrough-9.html">Next: Replacing the Print Dialog</a> ] -<p> We are ready to start replacing the <em>View</em> widget. However, our -example program uses the <tt>XmNotebook</tt> widget class. TQt does not -provide a direct equivalent of this class, so we are faced with three -possibilities, each with several advantages and disadvantages. -<p> <ol type=1> -<p> <li> We can continue the conversion using existing TQt widgets. -<p> <ul> -<p> <li> Advantages - The widgets provided by TQt are well designed and -tested, allowing us to quickly redesign the user interface. -<p> <li> Disadvantages - Most, if not all, of the existing data structures -and code will need to be modified or rewritten. New code must be -written in a way that maintains compatibility with previous versions -of our application. -<p> </ul> -<p> <li> We can write a new <a href="tqwidget.html">TQWidget</a> subclass that is identical to the <tt>XmNotebook</tt> widget class. -<p> <ul> -<p> <li> Advantages - The existing data structures will not change, allowing -compatibility with previous and future versions. -<p> <li> Disadvantages - The new widget will need to be written and -regression tested. Existing code in our application will need to be -changed in order to deal with the new widget's API. -<p> </ul> -<p> <li> We can leave the <tt>XmNotebook</tt> widget untouched. -<p> <ul> -<p> <li> Advantages - The existing data structures and code remain -unchanged, allowing us to continue development on other projects, -new features, etc. -<p> <li> Disadvantages - This is the simplest solution, but the application -will still be dependent upon X11; we will not be able to deploy our -application on all platforms supported by TQt. -<p> </ul> -<p> </ol> -<p> We will use the first approach to complete the migration of the -example project used in this walkthrough, using <a href="tqtextedit.html">TQTextEdit</a>, <a href="tqlabel.html">TQLabel</a> and -<a href="tqspinbox.html">TQSpinBox</a> to provide a similar look. The only difference is that we -will not have tabs. -<p> We use <a href="designer-manual.html">TQt Designer</a> to add the -TQTextEdit, TQLabel and TQSpinBox widgets to the <em>Main Window</em> widget. -<p> <h2> Data Structure Modifications -</h2> -<a name="1"></a><p> The <tt>Page</tt> struct contains <tt>majorPB</tt> and <tt>minorPB</tt> members which -need to be removed. These members correspond to the tabs displayed in -the existing version. The new version will not have any tabs, so we -remove them. -<p> - -<pre></pre> -<p> <h2> Code Modifications -</h2> -<a name="2"></a><p> Most of the existing functions in our application need to be modified -to work with the new <em>View</em> widget. The <tt>MainWindow</tt> class has five -new functions that correspond to existing functions. -<p> <center><table cellpadding="4" cellspacing="2" border="0"> -<tr bgcolor="#a2c511"> <th valign="top">Existing Function <th valign="top">New Function -<tr bgcolor="#f0f0f0"> <td valign="top"><tt>void SetPage( int )</tt> <td valign="top"><tt>void MainWindow::setPage( int )</tt> -<tr bgcolor="#d0d0d0"> <td valign="top"><tt>void PageChange( ... )</tt> <td valign="top"><tt>void MainWnidow::pageChange( int )</tt> -<tr bgcolor="#f0f0f0"> <td valign="top"><tt>void TextChanged( ... )</tt> <td valign="top"><tt>void MainWnidow::textChanged()</tt> -<tr bgcolor="#d0d0d0"> <td valign="top"><tt>void ReadDB( char * )</tt> <td valign="top"><tt>void MainWindow::readDB( char * )</tt> -<tr bgcolor="#f0f0f0"> <td valign="top"><tt>void SaveDB( char * )</tt> <td valign="top"><tt>void MainWindow::saveDB( char * )</tt> -</table></center> -<p> <a name="mainwindow-ui-h-view-widget-modifications"></a> -<p> The <tt>SetPage()</tt> function implementation is moved to the <tt>MainWindow::setPage()</tt> function in <tt>mainwindow.ui.h</tt>. We remove the -<tt>SetPage()</tt> function declaration and implementation from <tt>page.h</tt> -and <tt>actions.cpp</tt>, respectively. In order to make <tt>MainWindow::setPage()</tt> work correctly, we need to modify the code to -use the new widgets in our <em>Main Window</em> widget. -<p> - -<pre></pre> -<p> First, we set the current value of the <tt>spinbox</tt> to the current page -number. -<p> <pre></pre> -<p> Next, we set the current text and cursor position of the <tt>textedit</tt> -to the contents of the current page. -<p> <pre></pre> -<p> If the current page has a custom label, we set it as the current text -of the <tt>textlabel</tt>; otherwise we set the <tt>textlabel</tt> contents to -"Page X" (where X is the current page number). -<p> <pre></pre> -<p> If the current page has major and/or minor tab text, we append these -to the <tt>labeltext</tt>. This ensures that all information entered by the -user remains visible. -<p> <pre></pre> -<p> We should continue to handle the possibility that the current page -does not exist. In this case, we clear the contents of the <tt>textedit</tt> widget and set the <tt>textlabel</tt> contents to the current page -number (with an indication that the page is invalid). -<p> <pre></pre> -<p> The <tt>PageChange()</tt> function is moved from <tt>todo.cpp</tt> to the <tt>MainWindow::pageChange()</tt> function in <tt>mainwindow.ui.h</tt>. As with the -<tt>MainWindow::setPae()</tt> function, we need to modify the code to use -the new widgets in our <em>Main Window</em> widget. -<p> Note: <a href="tqtextedit.html#text">TQTextEdit::text</a>() returns a <a href="tqstring.html">TQString</a>, which needs to be converted -into a normal <tt>char*</tt> array. To do this we create a copy of the -string in the local encoding. We need to make the copy using <a href="tqcstring.html#qstrdup">tqstrdup</a>() because the data contained in the <a href="tqcstring.html">TQCString</a> returned by -<a href="tqstring.html#local8Bit">TQString::local8Bit</a>() is deallocated when the TQCString is destroyed. -<p> <pre></pre> -<p> The <tt>TextChanged()</tt> function does nothing more than set the <tt>modified</tt> variable to 1. Our new <tt>MainWindow::textChanged()</tt> function -does exactly the same. -<p> <pre></pre> -<p> Since both the <tt>MainWindow::pageChange()</tt> and <tt>MainWindow::textChanged()</tt> functions access the <tt>modified</tt> global -variable, we add a forward declaration at the top of <tt>mainwindow.ui.h</tt>. -<p> <a name="io-cpp-view-widget-modifications"></a> -<p> The <tt>ReadDB()</tt> and \s SaveDB() implementations in <tt>io.cpp</tt> are -renamed to <tt>MainWindow::readDB()</tt> and <tt>MainWindow::saveDB()</tt>, -respectively. We need to modify the code in order to make the code -work properly. -<p> First, We add <tt>#include</tt> statements for the <tt>MainWindow</tt>, <a href="tqspinbox.html">TQSpinBox</a> -and <a href="tqtextedit.html">TQTextEdit</a> classes. -<p> - -<pre></pre><pre></pre> -<p> The new <tt>MainWindow::readDB()</tt> and <tt>MainWindow::saveDB()</tt> functions -will not use any Xt/Motif functions, so we remove the Xt/Motif <tt>#include</tt> statements and the global variables <tt>notebook</tt> and <tt>textw</tt>. -These functions remain largely unchanged, maintaining compatibility -with previous versions. Also, the <tt>ReadDB()</tt> and <tt>SaveDB()</tt> -functions have been converted into <tt>MainWindow</tt> member functions, so -we can pass <em>this</em> as the <em>parent</em> argument to the <a href="tqmessagebox.html">TQMessageBox</a> -functions. -<p> <pre></pre> -<p> After reading the file in the <tt>MainWindow::readDB()</tt> function, we set -the current and maximum values of the <tt>spinbox</tt> to the appropriate -values. -<p> - -<p> <pre></pre> -<p> In the <tt>MainWindow::saveDB()</tt> function, we need to store the text -currently displayed, so we use <a href="tqtextedit.html#text">TQTextEdit::text</a>() instead of <tt>XmTextGetString()</tt>. Note: TQTextEdit::text() returns a <a href="tqstring.html">TQString</a>, which -needs to be converted into a normal <tt>char*</tt> array. To do this we -create a copy of the string in the local encoding. We need to make -the copy using <a href="tqcstring.html#qstrdup">tqstrdup</a>() because the data contained in the <a href="tqcstring.html">TQCString</a> -returned by <a href="tqstring.html#local8Bit">TQString::local8Bit</a>() is deallocated when the TQCString is -destroyed. -<p> <pre></pre> -<p> <a name="actions-cpp-viewwidget-modifications"></a> -<p> Due to the removal of the <tt>majorPB</tt> and <tt>minorPB</tt> members from the -<tt>Page</tt> struct, the <tt>FixPages()</tt> function in <tt>actions.cpp</tt> is no -longer needed. We remove the implementation and forward declaration -of <tt>FixPages()</tt> from <tt>actions.cpp</tt> and <tt>page.h</tt>, respectively. -Calls to <tt>FixPages()</tt> are removed from the <tt>MainWindow::selNewPage()</tt> and <tt>MainWindow::selDeletePage()</tt>, both of -which are in <tt>mainwindow.ui.h</tt>. -<p> We move <tt>AdjustPages()</tt> to <tt>mainwindow.ui.h</tt> and make it <tt>static</tt>, -since it is only used in this file. We remove the forward declaration -from <tt>page.h</tt> as well. -<p> After our modifications, the <tt>actions.cpp</tt> file is empty. We remove -it from our project file and regenerate our <tt>Makefile</tt>. -<p> <a name="todo-cpp-view-widget-modifications"></a> -<p> Now that we have implemented our new <em>View</em> widget, we need to remove -the old <a href="motif-extension.html#Motif">Motif</a> based view widget from <tt>todo.cpp</tt>. -<p> Since we will not be using any Motif widgets, we remove all Motif <tt>#include</tt> statements, including <a href="tqmotifwidget-h.html">tqmotifwidget.h</a>. -<p> - -<pre></pre><pre></pre> -<p> We also remove the forward declarations of the <tt>ReadDB()</tt> function -and the <tt>notebook</tt>, <tt>textw</tt> and <tt>labelw</tt> global variables. -<p> <pre></pre> -<p> Next, we remove the <tt>center</tt> widget, which uses <a href="tqmotifwidget.html">TQMotifWidget</a>. The <em>Main Window</em> widget and <em>View</em> widget are contained entirely in our -<tt>MainWindow</tt> class, so no extra initialization is needed after -creating the <tt>mainwindow</tt> widget. -<p> <pre></pre> -<p> Since the <tt>ReadDB()</tt> and <tt>SetPage()</tt> functions have been changed into -<tt>MainWindow</tt> member functions, we need to call them using our <tt>mainwindow</tt> instance. -<p> <pre></pre> -<p> The <em>View</em> widget has now been replaced. After building our project, -we confirm that the application works correctly. -<p> [ <a href="motif-walkthrough-7.html">Previous: Refactoring Existing Code</a> ] -[ <a href="motif-walkthrough.html">Home</a> ] -[ <a href="motif-walkthrough-9.html">Next: Replacing the Print Dialog</a> ] -<p> -<!-- eof --> -<p><address><hr><div align=center> -<table width=100% cellspacing=0 border=0><tr> -<td>Copyright © 2007 -<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> -<td align=right><div align=right>TQt 3.3.8</div> -</table></div></address></body> -</html> |