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diff --git a/doc/html/porting2.html b/doc/html/porting2.html deleted file mode 100644 index cfa84fd..0000000 --- a/doc/html/porting2.html +++ /dev/null @@ -1,965 +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/doc/porting2.doc:36 --> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> -<title>Porting to Qt 2.x</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>Porting to Qt 2.x</h1> - - - -<p> <p> -You're probably looking at this page because you want to port -your application from Qt 1.x to Qt 2.x, but to be sure, let's -review the good reasons to do this: -<ul> -<li>To get access to all the new Qt 2.x features like the rich text -HTML subset for formatted labels, tooltips, online help etc. -and the much easier to use layout classes and widgets. -<li>To make your application truly international, with support -for Unicode and translations for the languages of the world. -<li>To allow your application to fit into the new look of the -Unix desktop with configurable, very powerful "themes". The -extended style system also integrates Qt applications better -on MS-Windows desktops. Qt will automatically chose the right -colors and fonts and obey global system setting changes. -<li>To stay up-to-date with the version of Qt that gets all the -new features and bug-fixes. -<li>To get more speed and smoother widgets display with all the -new anti-flicker changes in Qt. -<li>Most of all though, you want to port to Qt 2.x -so that your Wheel Mouse works! -</ul> -<p> <p> -The Qt 2.x series is not binary compatible with the 1.x series. -This means programs compiled for Qt 1.x must be recompiled to work -with Qt 2.x. Qt 2.x is also not completely <em>source</em> compatible -with 1.x, however all points of incompatibility cause -compiler errors (rather than mysterious results), or produce run-time -messages. The result is that Qt 2.x includes many additional features, -discards obsolete functionality that is easily converted to use the new -features, and that porting an application from Qt 1.x to Qt 2.x is -a simple task well worth the amount of effort required. -<p> To port code using Qt 1.x to use Qt 2.x: -<p> <ul> -<li> Briefly read the porting notes below to get an idea of what to expect. -<li> Be sure your code compiles and runs well on all your target platforms with Qt 1.x. -<li> Recompile with Qt 2.x. For each error, search below for related -identifiers (eg. function names, class names) - this documented is -structured to mention all relevant identifiers to facilitate such -searching, even if that makes it a little verbose. -<li> If you get stuck, ask on the qt-interest mailing list, or -Trolltech Technical Support if you're a Professional Edition -licensee. -</ul> -<p> Many very major projects, such as <a href="http://www.kde.org/">KDE</a> -have been port, so there is plenty of expertise in the collective conscious -that is the Qt Developer Community! -</p> -<p> <hr> -<p> <h2 align=center>The Porting Notes</h2> -<p> <ul> -<li><b><a href="#Namespace">Namespace</a></b> -<li><b><a href="#Virtual">Virtual Functions</a></b> -<li><b><a href="#Collection">Collection classes</a></b> -<li><b><a href="#DefaultParent">No Default 0 Parent Widget</a></b> -<li><b><a href="#DebugVsRelease">Debug vs. Release</a></b> -<li><b><a href="#QApplication">QApplication</a></b> -<li><b><a href="#QClipboard">QClipboard</a></b> -<li><b><a href="#QColor">QColor</a></b> -<li><b><a href="#QDataStream">QDataStream</a></b> -<li><b><a href="#QDialog">QDialog</a></b> -<li><b><a href="#QDropSite">QDropSite</a></b> -<li><b><a href="#QEvent">QEvent</a></b> -<li><b><a href="#QFile">QFile</a></b> -<li><b><a href="#QFontMetrics">QFontMetrics</a></b> -<li><b><a href="#QIODevice">QIODevice</a></b> -<li><b><a href="#QLabel">QLabel</a></b> -<li><b><a href="#QLayout">QLayout</a></b> -<li><b><a href="#QListView">QListView</a></b> -<li><b><a href="#QMenuData">QMenuData</a></b> -<li><b><a href="#QMenuData">QPopupMenu</a></b> -<li><b><a href="#QMultiLineEdit">QMultiLineEdit</a></b> -<li><b><a href="#QPainter">QPainter</a></b> -<li><b><a href="#QPicture">QPicture</a></b> -<li><b><a href="#QPoint">QPoint, <a href="qpointarray.html">QPointArray</a>, <a href="qsize.html">QSize</a> and <a href="qrect.html">QRect</a></a></b> -<li><b><a href="#QPixmap">QPixmap</a></b> -<li><b><a href="#QRgb">QRgb</a></b> -<li><b><a href="#QScrollView">QScrollView</a></b> -<li><b><a href="#QStrList">QStrList</a></b> -<li><b><a href="#QString">QString</a></b> -<li><b><a href="#QTextStream">QTextStream</a></b> -<li><b><a href="#QUriDrag">QUriDrag / QUrlDrag</a></b> -<li><b><a href="#QValidator">QComboBox</a></b> -<li><b><a href="#QValidator">QLineEdit</a></b> -<li><b><a href="#QValidator">QSpinBox</a></b> -<li><b><a href="#QValidator">QValidator</a></b> -<li><b><a href="#QWidget">QWidget</a></b> -<li><b><a href="#QWindow">QWindow</a></b> -</ul> -<p> <hr> -<p> <h3><a name="Namespace">Namespace</a></h3> -<p> <p> Qt 2.x is namespace-clean, unlike 1.x. Qt now uses very few -global identifiers. Identifiers like <code>red, blue, LeftButton, -AlignRight, Key_Up, Key_Down, NoBrush</code> etc. are now part of a -special class <code>Qt</code> (defined in qnamespace.h), -which is inherited by -most Qt classes. Member functions of classes that inherit from <a href="qwidget.html">QWidget</a>, -etc. are totally unaffected, but code that is -<em>not</em> in functions of classes inherited from <code>Qt</code>, -you must qualify these identifiers like this: <code>Qt::red, -Qt::LeftButton, Qt::AlignRight</code>, etc. -<p> <p>The <code>qt/bin/qt20fix</code> script helps to fix the code that -needs adaption, though most code does not need changing. -<p> Compiling with -DQT1COMPATIBILITY will help you get going with Qt 2.x -- it allows all the old "dirty namespace" identifiers from Qt 1.x to -continue working. Without it, you'll get compile errors that can -easily be fixed by searching this page for the clean identifiers. -<p> <h3><a name="DefaultParent">No Default 0 Parent Widget</a></h3> -<p> In Qt 1.x, all widget constructors were defined with a default value -of 0 for the parent widget. However, only the main window of the -application should be created with a 0 parent, all other widgets -should have parents. Having the 0 default made it too simple to create -bugs by forgetting to specify the parent of non-mainwindow -widgets. Such widgets would typically never be deleted (causing memory -leaks), and they would become top-level widgets, confusing the window -managers. Therefore, in Qt 2.x the 0 default parent has been removed -for the widget classes that are not likely to be used as main windows. -<p> Note also that programs no longer need (or should) use 0 parent just -to indicate that a widget should be top-level. See -<pre> QWidget::isTopLevel() </pre> - for details. See also the notes about -<a href="#QMenuData">QPopupMenu</a> and <a href="#QDialog">QDialog</a> -below. -<p> <h3><a name="Virtual">Virtual Functions</a></h3> -<p> <p> Some virtual functions have changed signature in Qt 2.x. -If you override them in derived classes, you must change the signature -of your functions accordingly. -<p> <!-- warwick can check for additions to this with his qt-2-report --> -<ul> -<li><pre> QWidget::setStyle(GUIStyle)</pre> - -<li><pre> QListView::addColumn(const char *, int)</pre> - -<li><pre> QListView::setColumnText(int, const char *)</pre> - -<li><pre> QListViewItem::setText(int, const char *)</pre> - -<li><pre> QMultiLineEdit::insertLine(const char *, int)</pre> - -<li><pre> QMultiLineEdit::insertAt(const char *, int, int, bool)</pre> - -<li><pre> QSpinBox::setPrefix(const char *)</pre> - -<li><pre> QSpinBox::setSuffix(const char *)</pre> - -<li><pre> QToolButton::setTextLabel(const char *, bool)</pre> - -<li><pre> QDoubleValidator::validate(QString &, int &)</pre> - -<li><pre> QIntValidator::validate(QString &, int &)</pre> - -<li><pre> QValidator::fixup(QString &)</pre> - -<li><pre> QSlider::paintSlider(QPainter *, const <a href="qrect.html">QRect</a> &)</pre> - -</ul> -<p> This is one class of changes that are -not detected by the compiler, -so you should mechanically search for each of -these function names in your header files, eg. -<p> <pre> -egrep -w 'setStyle|addColumn|setColumnText|setText...' *.h -</pre> - -<p> Of course, you'll get a few false positives (eg. if you have a setText -function that is not in a subclass of <a href="qlistviewitem.html">QListViewItem</a>). -<p> <h3><a name="Collection">Collection classes</a></h3> -<p> <p> The <a href="collection.html#collection-classes">collection classes</a> include generic -classes such as QGDict, QGList, and -the subclasses such as <a href="qdict.html">QDict</a> and QList. -<p> <p> The macro-based Qt collection classes are obsolete; use the -template-based classes instead. Simply remove includes of qgeneric.h and -replace e.g. Q_DECLARE(<a href="qcache.html">QCache</a>,QPixmap) with QCache<QPixmap>. -<p> <p> The GCI global typedef is replaced by QCollection::Item. Only if you -make your own subclasses of the undocumented generic collection classes -will you have GCI in your code. -This change has been made to avoid collisions with other namespaces. -<p> <p> The GCF global typedef is removed (it was not used in Qt). -<p> <h3><a name="DebugVsRelease">Debug vs. Release</a></h3> -<p> <p>The Q_ASSERT macro is now a null expression if the QT_CHECK_STATE flag -is not set (i.e. if the QT_NO_CHECK flag is defined). -<p> <p>The debug() function now outputs nothing if Qt was compiled with -the QT_NO_DEBUG macro defined. -<p> <h3><a name="QString">QString</a></h3> -<p> <a href="qstring.html">QString</a> has undergone major changes internally, and although it is highly -backward compatible, it is worth studying in detail when porting to Qt 2.x. -The Qt 1.x QString class has been renamed to <a href="qcstring.html">QCString</a> in Qt 2.x, though if -you use that you will incur a performance penalty since all Qt functions -that took const char* now take const QString&. -<p> <p> -To take full advantage of the new <a href="i18n.html#internationalization">Internationalization</a> -functionality in Qt 2.x, the following steps are required: -<p> <ul> -<li> Start converting all uses of "const char*" in parameters to -"const QString&" - this can often be done mechanically, eg. -using Perl. Convert usage of char[] for temporary string -building to QString (much software already uses QString for -this purpose as it offers many more facilities). -<p> If you find that you are mixing usage of QCString, QString, -and <a href="qbytearray.html">QByteArray</a>, this causes lots of unnecessary copying and -might indicate that the true nature of the data you are -dealing with is uncertain. If the data is NUL-terminated -8-bit data, use QCString; if it is unterminated (ie. -contains NULs) 8-bit data, use QByteArray; if it is text, -use <a href="qstring.html">QString</a>. -</p> -<li> Put a breakpoint in <pre> QString::latin1()</pre> - -to catch places where -Unicode information is being converted to ASCII (loosing -information if your user in not using Latin1). Qt has -a small number of calls to this - ignore those. As a stricter -alternative, compile your code with QT_NO_ASCII_CAST defined, -which hides the automatic conversion of QString to const char*, -so you can catch problems at compile time. -</p> -<li> See the Qt <a href="i18n.html">Internationalization page</a> -for information about the full process of internationalizing -your software. -</ul> -<p> <p> -Points to note about the new QString are: -<p> <dl compact> -<dt><b>Unicode</b></dt> -<dd> -Qt now uses Unicode throughout. -data() now returns a <em>const</em> reference to an ASCII version -of the string - you cannot directly access the -string as an array of bytes, because it isn't one. Often, latin1() is -what you want rather than data(), or just leave it to convert to -const char* automatically. data() is only used now to aide porting to Qt 2.x, -and ideally you'll only need latin1() or implicit conversion when interfacing -to facilities that do not have Unicode support. -<p> <dt><b>Automatic-expanding</b></dt> -<dd> -A big advantage of the new <a href="qstring.html">QString</a> is that it automatically expands -when you write to an indexed position. -<p> <dt><b>QChar and <a href="qcharref.html">QCharRef</a></b></dt> -<dd> -<a href="qchar.html">QChar</a> are the Unicode characters that make up a QString. A QCharRef is -a temporary reference to a QChar in a QString that when assigned to -ensures that the <a href="shclass.html#implicit-sharing">implicit sharing</a> semantics of the QString are maintained. -You are unlikely to use QCharRef in your own code - but so that you -understand compiler error messages, just know that <tt>mystring[123]</tt> -is a QCharRef whenever <tt>mystring</tt> is not a constant string. A QCharRef -has basically the same functionality as a QChar, except it is more restricted -in what you can assign to it and cast it to (to avoid programming errors). -<p> <dt><b>Use QString</b></dt> -<dd> -Try to always use QString. If you <em>must</em>, use <a href="qcstring.html">QCString</a> which is the -old implementation from Qt 1.x. -<p> <dt><b>Unicode vs. ASCII</b></dt> -<dd> -Every conversion to and from ASCII is wasted time, so try to use <a href="qstring.html">QString</a> -as much as possible rather than const char*. This also ensures you have -full 16-bit support. -<p> <dt><b>Convertion to ASCII</b></dt> -<dd> -The return value from operator const char*() is transient - don't expect -it to remain valid while you make deep function calls. -It is valid for as long as you don't modify or destroy the QString. -<p> <dt><b>QString is simpler</b></dt> -<dd> -Expect your code to become simpler with the new QString, especially -places where you have used a char* to wander over the string rather -than using indexes into the string. -<p> <dt><b>Some hacks don't work</b></dt> -<dd> -This hack: -use_sub_string( &my_string[index] ) -should be replaced by: -use_sub_string( my_string.mid(index) ) -<p> <dt><b>QString(const char*, int) is removed</b></dt> -<dd> -The QString constructor taking a const char* and an integer is removed. -Use of this constructor was error-prone, since the length included the -'\0' terminator. Use <a href="qstring.html#left">QString::left</a>(int) or <a href="qstring.html#fromLatin1">QString::fromLatin1</a>( const char*, -int ) -- in both cases the int parameter signifies the number of characters. -<p> <dt><b>QString(int) is private</b></dt> -<dd> -The <a href="qstring.html">QString</a> constructor taking an integer is now private. This function -is not meaningful anymore, since QString does all space allocation -automatically. 99% of cases can simple be changed to use the -default constructor, QString(). -<p> -In Qt 1.x the constructor was used in two ways: accidentally, -by attempting to convert a char to a QString (the char converts to int!) - -giving strange bugs, and as a way to make a QString big enough prior to -calling <pre> QString::sprintf()</pre> - . In Qt 2.x, the accidental bug case is -prevented (you will get a compilation error) and QString::sprintf has -been made safe - you no longer need to pre-allocate space (though for -other reasons, sprintf is still a poor choice - eg. it doesn't pass Unicode). -The only remaining common case is conversion of 0 (NULL) to QString, which -would usually give expected results in Qt 1.x. For Qt 2.x the correct -syntax is to use <a href="qstring.html#QString-null">QString::null</a>, though note that -the default constructor, QString(), creates a null string too. -Assignment of 0 to a <a href="qstring.html">QString</a> is ambiguous - assign -QString::null; you'll mainly find these in code that has been converted -from const char* types to QString. -This also prevents a common error case from Qt 1.x - in -that version, mystr = 'X' would <em>not</em> produce the expected -results and was always a programming error; in Qt 2.x, it works - making -a single-character string. -<p> <p> -Also see <a href="#QStrList">QStrList</a>. -<p> <dt><b>Signals and Slots</b></dt> -<dd> -Many signal/slots have changed from const char* to QString. You will -get run-time errors when you try to <pre> QObject::connect()</pre> - -to the old -signals and slots, usually with a message indicating the const QString& -replacement signal/slot. -<p> <dt><b>Optimize with Q2HELPER</b></dt> -<dd> -In qt/src/tools/qstring.cpp there is a Q2HELPER - define it for some -extra debugging/optimizing features (don't leave it it - it kills performance). -You'll get an extra function, qt_qstring_stats(), which will print a -summary of how much your application is doing Unicode and ASCII -back-and-forth conversions. -<p> <dt><b>QString::detach() is obsolete and removed</b></dt> -<dd> -Since <a href="qstring.html">QString</a> is now always shared, this function does nothing. -Remove calls to QString::detach(). -<p> <dt><b>QString::resize(int size) is obsolete and removed</b></dt> -<dd> -Code using this to truncate a string should use -<a href="qstring.html#truncate">truncate(size-1)</a>. -Code using qstr.resize(0) should use qstr = QString::null. -Code calling resize(n) prior to using -<a href="qstring.html#operator[]">operator[]</a> up to n just remove -the resize(n) completely. -<p> <dt><b>QString::size() is obsolete and removed</b></dt> -<dd> -Calls to this function must be replaced by -<a href="qstring.html#length">length()</a>+1. -<p> <dt><b>QString::setStr(const char*) is removed</b></dt> -<dd>Try to understand why you were using this. -If you just meant assignment, use that. Otherwise, -you are probably using QString as an array of bytes, in which case use -<a href="qbytearray.html">QByteArray</a> or <a href="qcstring.html">QCString</a> instead. -<p> <dt><b>QString is not an array of bytes</b></dt> -<dd> -Code that uses <a href="qstring.html">QString</a> as an array of bytes should use QByteArray -or a char[], <em>then</em> convert that to a QString if needed. -<p> <dt><b>"string = 0"</b></dt> -<dd> -Assigning 0 to a QString should be assigning the null string, -ie. string = QString::null. -<p> <dt><b>System functions</b></dt> -<dd> -You may find yourself needing latin1() for passing to the operating system -or other libraries, and be tempted to use QCString to save the conversion, -but you are better off using Unicode throughout, then when the operating -system supports Unicode, you'll be prepared. Some Unix operating systems -are now beginning to have basic Unicode support, and Qt will be tracking -these improvements as they become more widespread. -<p> <dt><b>Bugs removed</b></dt> -<dd> -toShort() returns 0 (and sets *ok to false) on error. -toUInt() now works for big valid unsigned integers. -insert() now works into the same string. -<p> <dt><b>NULL pointers</b></dt> -<dd> -When converting "const char*" usage to QString in order to make your -application fully Unicode-aware, use QString::null for the null value -where you would have used 0 with char pointers. -<p> <dt><b>QString is not null terminated</b></dt> -<dd> -This means that inserting a 0-character -in the middle of the string does <em>not</em> change the length(). ie. -<pre> - <a href="qstring.html">QString</a> s = "fred"; - s[1] = '\0'; - // s.<a href="qstring.html#length">length</a>() == 4 - // s == "f\0ed" - // s.<a href="qstring.html#latin1">latin1</a>() == "f" - s[1] = 'r'; - // s == "fred" - // s.<a href="qstring.html#latin1">latin1</a>() == "fred" - </pre> - -Especially look out for this type of code: -<pre> - <a href="qstring.html">QString</a> s(2); - s[0] = '?'; - s[1] = 0; - </pre> - -This creates a string 2 characters long. -To find these problems while converting, you might like to -add <a href="qapplication.html#Q_ASSERT">Q_ASSERT</a>(strlen(d->ascii)==d->len) inside -<pre> QString::latin1()</pre> - . -<p> <dt><b>QString or Standard C++ string?</b></dt> -<dd> -<p> -The Standard C++ Library string is not Unicode. Nor is wstring defined -to be so (for the small number of platforms where it is defined at all). -This is the same mistake made over and over -in the history of C - only when non-8-bit characters are <em>the norm</em> -do programmers find them usable. Though it is possible to convert between -string and <a href="qstring.html">QString</a>, it is less efficient than using QString throughout. -For example, when using: -<pre> - QLabel::<a href="qlabel.html#setText">setText</a>( const <a href="qstring.html">QString</a>& ) -</pre> - -if you use string, like this: -<pre> - void myclass::dostuffwithtext( const string& str ) - { - mylabel.setText( QString(str.c_str()) ); - } -</pre> - -that will create a (ASCII only) copy of str, stored in mylabel. -But this: -<pre> - void myclass::dostuffwithtext( const <a href="qstring.html">QString</a>& str ) - { - mylabel.setText( str ); - } -</pre> - -will make an <a href="shclass.html#implicitly-shared">implicitly shared</a> reference to str in the <a href="qlabel.html">QLabel</a> - no copying -at all. This function might be 10 nested function calls away from something -like this: -<pre> - void toplevelclass::initializationstuff() - { - doStuff( tr("Okay") ); - } -</pre> - -At this point, in Qt 2.x, the tr() does a very fast dictionary lookup -through memory-mapped message files, returning some Unicode <a href="qstring.html">QString</a> for -the appropriate language (the default being to just make a QString out -of the text, of course - you're not <em>forced</em> to use any of these -features), and that <em>same</em> memory mapped Unicode will be passed -though the system. All occurrences of the translation of "Okay" can -potentially be shared. -<p> </dl> -<p> <h3><a name="QApplication">QApplication</a></h3> -<p> In the function <pre> QApplication::setColorSpec()</pre> - , -PrivateColor and TrueColor are obsolete. Use ManyColor instead. -<p> <h3><a name="QColor">QColor</a></h3> -<p> <p> -All colors -(color0, -color1, -black, -white, -darkGray, -gray, -lightGray, -red, -green, -blue, -cyan, -magenta, -yellow, -darkRed, -darkGreen, -darkBlue, -darkCyan, -darkMagenta, -and -darkYellow) -are in the Qt namespace. -In members of classes that inherit the Qt namespace-class (eg. <a href="qwidget.html">QWidget</a> -subclasses), you can use the unqualified names as before, but in global -functions (eg. main()), you need to qualify them: Qt::red, Qt::white, etc. -See also the <a href="#QRgb">QRgb</a> section below. -<p> <h3><a name="QRgb">QRgb</a></h3> -<p> In QRgb (a typedef of long), the order of the RGB channels has changed to -be in the more efficient order (for typical contemporary hardware). If your -code made assumptions about the order, you will get blue where you expect -red and vice versa (you'll not notice the problem if you use shades of -gray, green, or magenta). You should port your code to use the -creator function <a href="qcolor.html#qRgb">qRgb</a>(int r,int g,int b) and the -access functions <a href="qcolor.html#qRed">qRed</a>(QRgb), <a href="qcolor.html#qBlue">qBlue</a>(QRgb), and <a href="qcolor.html#qGreen">qGreen</a>(QRgb). -If you are using the alpha channel, it hasn't moved, but you should use -the functions <a href="qcolor.html#qRgba">qRgba</a>(int,int,int,int) and <a href="qcolor.html#qAlpha">qAlpha</a>(QRgb). Note also that -<a href="qcolor.html#pixel">QColor::pixel</a>() does <i>not</i> return a QRgb (it never did on all platforms, -but your code may have assumed so on your platform) - this may also produce -strange color results - use <a href="qcolor.html#rgb">QColor::rgb</a>() if you want a QRgb. -<p> <h3><a name="QDataStream">QDataStream</a></h3> -<p> <p>The QDatastream serialization format of most Qt classes is changed -in Qt 2.x. Use <pre> QDataStream::setVersion( 1 )</pre> - to get a -datastream object that can read and write Qt 1.x format data streams. -<p> <p>If you want to write Qt 1.x format datastreams, note the following -compatibility issues: -<ul> -<li>QString: Qt 1.x has no Unicode support, so strings will be -serialized by writing the classic C string returned by <pre> - QString::<a href="qstring.html#latin1">latin1</a>().</pre> - -<li><a href="#QPoint">QPoint & al.</a>: Coordinates will be -truncated to the Qt 1.x 16 bit format. -</ul> -<p> <h3><a name="QWidget">QWidget</a></h3> -<p> <h4>QWidget::recreate()</h4> -<p> -This function is now called <a href="qwidget.html#reparent">reparent()</a>. -<p> <h4>QWidget::setAcceptFocus(bool)</h4> -<p> -This function is removed. -Calls like QWidget::setAcceptFocus(TRUE) should be replaced by -<pre> QWidget::setFocusPolicy(StrongFocus)</pre> - , and -calls like QWidget::setAcceptFocus(FALSE) should be replaced by -<pre> QWidget::setFocusPolicy(NoFocus)</pre> - . -Additional policies are TabFocus and ClickFocus. -<p> <h4>QWidget::paintEvent()</h4> -<p> -paintEvent(0) is not permitted - subclasses need not check for -a null event, and might crash. -Never pass 0 as the argument to paintEvent(). You probably -just want repaint() or update() instead. -<p> -When processing a paintEvent, painting is only permitted within -the update region specified in the event. Any painting outside will be -clipped away. This shouldn't break any code (it was always like this -on MS-Windows) but makes many explicit calls to -<a href="qpainter.html#setClipRegion">QPainter::setClipRegion</a>() superfluous. Apart from the improved -consistency, the change is likely to reduce flicker and to make Qt -event slightly faster. -<p> <h3><a name="QIODevice">QIODevice</a></h3> -<p> -The protected member QIODevice::index is renamed to QIODevice::ioIndex -to avoid warnings and to allow compilation with bad C libraries that -#define index to strchr. If you have made a subclass of <a href="qiodevice.html">QIODevice</a>, -check every occurrence of the string "index" in the implementation, since -a compiler will not always catch cases like <pre>(uint)index</pre> - -that need to be changed. -<p> <h3><a name="QLabel">QLabel</a></h3> -<p> <h4><pre> QLabel::setMargin()</pre> - </h4> -<p> -<pre> QLabel::setMargin()</pre> - and<pre> QLabel::margin()</pre> - -have been renamed to <pre> QLabel::setIndent()</pre> - and -<pre> QLabel::indent()</pre> - , respectively. This was done to avoid -collision with <a href="qframe.html#setMargin">QFrame::setMargin</a>(), which is now virtual. -<p> <h4><pre> QLabel::setMovie()</pre> - </h4> -<p> -Previously, setting a movie on a label cleared the value of text(). -Now it doesn't. If you somehow used <tt>QLabel::text()</tt> -to detect if a -movie was set, you might have trouble. This is unlikely. -<p> <h3><a name="QDialog">QDialog</a></h3> -<p> <p> The semantics of the parent pointer changed for modeless dialogs: -In Qt-2.x, dialogs are always top level windows. The parent, however, -takes the ownership of the dialog, i.e. it will delete the dialog at -destruction if it has not been explicitly deleted -already. Furthermore, the window system will be able to tell that both -the dialog and the parent belong together. Some X11 window managers -will for instance provide a common taskbar entry in that case. -<p> <p> -If the dialog belongs to a top level main window -of your application, pass this main window as parent to the dialog's -constructor. Old code (with 0 pointer) will still run. Old code that -included QDialogs as child widgets will no longer work (it never really did). -If you think you might be doing this, put a breakpoint in -<a href="qdialog.html#QDialog">QDialog::QDialog</a>() conditional on parent not being 0. -<p> <h3><a name="QStrList">QStrList</a></h3> -<p> Many methods that took a <a href="qstrlist.html">QStrList</a> can now instead take a <a href="qstringlist.html">QStringList</a>, -which is a real list of <a href="qstring.html">QString</a> values. -<p> To use QStringList rather than QStrList, change loops that look like this: -<pre> - <a href="qstrlist.html">QStrList</a> list = ...; - const char* s; - for ( s = list.<a href="qptrlist.html#first">first</a>(); s; s = list.<a href="qptrlist.html#next">next</a>() ) { - process(s); - } -</pre> - -to be like this: -<pre> - <a href="qstringlist.html">QStringList</a> list = ...; - QStringList::ConstIterator i; - for ( i = list.<a href="qvaluelist.html#begin">begin</a>(); i != list.<a href="qvaluelist.html#end">end</a>(); ++i ) { - process(*i); - } -</pre> - -<p> In general, the QStrList functions are less efficient, building a temporary QStringList. -<p> The following functions now use QStringList rather than QStrList -for return types/parameters. -<p> <ul> -<li><tt>void <a href="qfiledialog.html#setFilters">QFileDialog::setFilters</a>(const <a href="qstrlist.html">QStrList</a>&)</tt> -becomes <tt>void QFileDialog::setFilters(const <a href="qstringlist.html">QStringList</a>&)</tt> -<li><tt>QStrList <a href="qfiledialog.html#getOpenFileNames">QFileDialog::getOpenFileNames</a>(...)</tt> -becomes <tt>QStringList QFileDialog::getOpenFileNames(...)</tt> -<li><tt>bool QUrlDrag::decodeLocalFiles(<a href="qmimesource.html">QMimeSource</a>*, QStrList&)</tt> -becomes <tt>bool <a href="quridrag.html#decodeLocalFiles">QUriDrag::decodeLocalFiles</a>(QMimeSource*, QStringList&)</tt> -<li><tt>const QStrList *QDir::entryList(...) const</tt> -becomes <tt>QStringList <a href="qdir.html#entryList">QDir::entryList</a>(...) const</tt> -(note that the return type is no longer a pointer). You may also -choose to use encodedEntryList(). -</ul> -<p> The following functions are added: -<ul> -<li><tt>QComboBox::insertStringList(const QStringList &, int index=-1)</tt> -<li><tt>QListBox::insertStringList(const QStringList &,int index=-1)</tt> -</ul> -<p> The rarely used static function <tt>void -QFont::listSubstitutions(<a href="qstrlist.html">QStrList</a>*)</tt> is replaced by <tt>QStringList -<a href="qfont.html#substitutions">QFont::substitutions</a>()</tt>. -<p> <h3><a name="QLayout">QLayout</a></h3> -<p> <p> Calling resize(0,0) or resize(1,1) will no longer work magically. -Remove all such calls. The default size of top level widgets will be their -<a href="qwidget.html#sizeHint">sizeHint()</a>. -<p> <p> The default implementation of <a href="qwidget.html#sizeHint">QWidget::sizeHint</a>() will no longer -return just an invalid size; if the widget has a layout, it will return -the layout's preferred size. -<p> <p> The special maximum MaximumHeight/Width is now QWIDGETSIZE_MAX, -not QCOORD_MAX. -<p> <p> <a href="qboxlayout.html#addWidget">QBoxLayout::addWidget()</a> -now interprets the <em>alignment</em> parameter more aggressively. A -non-default alignment now indicates that the widget should not grow to -fill the available space, but should be sized according to sizeHint(). -If a widget is too small, set the alignment to 0. (Zero indicates no -alignment, and is the default.) -<p> <p> The class QGManager is removed. Subclasses of <a href="qlayout.html">QLayout</a> need to be rewritten -to use the new, much simpler <a href="qlayout.html">QLayout API</a>. -<p> <p> For typical layouts, all use of -<a href="qwidget.html#setMinimumSize">setMinimumSize()</a> -and -<a href="qwidget.html#setFixedSize">setFixedSize()</a> -can be removed. -<a href="qlayout.html#activate">activate()</a> is no longer necessary. -<p> <p> -You might like to look at the <a href="qgrid.html">QGrid</a>, <a href="qvbox.html">QVBox</a>, and <a href="qhbox.html">QHBox</a> widgets - they offer -a simple way to build nested widget structures. -<p> <h3><a name="QListView">QListView</a></h3> -<p> <p>In Qt 1.x mouse events to the viewport where redirected to the -event handlers for the listview; in Qt 2.x, this functionality is -in <a href="qscrollview.html">QScrollView</a> where mouse (and other position-oriented) events are -redirected to viewportMousePressEvent() etc, which in turn translate -the event to the coordinate system of the contents and call -contentsMousePressEvent() etc, thus providing events in the most -convenient coordinate system. If you overrode QListView::MouseButtonPress(), -<a href="qwidget.html#mouseDoubleClickEvent">QListView::mouseDoubleClickEvent</a>(), <a href="qwidget.html#mouseMoveEvent">QListView::mouseMoveEvent</a>(), or -<a href="qwidget.html#mouseReleaseEvent">QListView::mouseReleaseEvent</a>() you must instead override -viewportMousePressEvent(), -viewportMouseDoubleClickEvent(), viewportMouseMoveEvent(), or -viewportMouseReleaseEvent() respectively. New code will usually override -contentsMousePressEvent() etc. -<p> <p>The signal <a href="qlistview.html#selectionChanged">QListView::selectionChanged</a>(<a href="qlistviewitem.html">QListViewItem</a> *) can now be -emitted with a null pointer as parameter. Programs that use the -argument without checking for 0, may crash. -<p> <h3><a name="QMultiLineEdit">QMultiLineEdit</a></h3> -<p> <p> -The protected function -<pre> QMultiLineEdit::textWidth(QString*)</pre> - -changed to -<pre> QMultiLineEdit::textWidth(const <a href="qstring.html">QString</a>&)</pre> - . -This is unlikely to be a problem, and you'll get a compile error -if you called it. -<p> <h3><a name="QClipboard">QClipboard</a></h3> -<p> <p> -<pre> QClipboard::pixmap()</pre> - now returns a <a href="qpixmap.html">QPixmap</a>, not a QPixmap*. -The pixmap -will be <a href="qpixmap.html#isNull">null</a> if no pixmap is on the -clipboard. <a href="qclipboard.html">QClipboard</a> now offers powerful MIME-based types on the -clipboard, just like drag-and-drop (in fact, you can reuse most of your -drag-and-drop code with clipboard operations). -<p> <h3><a name="QDropSite">QDropSite</a></h3> -<p> <P> -QDropSite is obsolete. If you simply passed <tt>this</tt>, just remove -the inheritance of QDropSite and call -<a href="qwidget.html#setAcceptDrops">setAcceptDrops(TRUE)</a> in the class -constructor. -If you passed something other than <tt>this</tt>, -your code will not work. A common case is passing -the -<a href="qscrollview.html#viewport">viewport()</a> of a <a href="qlistview.html">QListView</a>, -in which case, -override the -<a href="qscrollview.html#contentsDragMoveEvent">contentsDragMoveEvent()</a>, -etc. -functions rather than QListView's dragMoveEvent() etc. For other -cases, you will need to use an event filter to act on the drag/drop events -of another widget (as is the usual way to intercept foreign events). -<p> <h3><a name="QScrollView">QScrollView</a></h3> -<p> The parameters in the signal -<a href="qscrollview.html#contentsMoving">contentsMoving(int,int)</a> -are now positive rather than negative values, coinciding with -<a href="qscrollview.html#setContentsPos">setContentsPos()</a>. Search for -connections you make to this signal, and either change the slot they are -connected to such that it also expects positive rather than negative -values, or introduce an intermediate slot and signal that negates them. -<p> If you used drag and drop with <a href="qscrollview.html">QScrollView</a>, you may experience the problem -described for <a href="#QDropSite">QDropSite</a>. -<p> <h3><a name="QTextStream">QTextStream</a></h3> -<p> <p> -<pre> operator<<(QTextStream&, QChar&)</pre> - does not skip whitespace. -<pre> operator<<(QTextStream&, char&)</pre> - does, -as was the case with Qt 1.x. This is for backward compatibility. -<p> <h3><a name="QUriDrag">QUriDrag</a></h3> -<p> The class QUrlDrag is renamed to <a href="quridrag.html">QUriDrag</a>, and the API has been -broadened to include additional conversion routines, including -conversions to Unicode filenames (see the class documentation -for details). Note that in Qt 1.x -the QUrlDrag class used the non-standard MIME type "url/url", -while QUriDrag uses the standardized "text/uri-list" type. Other -identifiers affected by the Url to Uri change are -QUrlDrag::setUrls() and QUrlDrag::urlToLocalFile(). -<p> <h3><a name="QPainter">QPainter</a></h3> -<p> <p> The GrayText painter flag has been removed. Use -<a href="qpainter.html#setPen">setPen( palette().disabled().foreground() )</a> -instead. -<p> <p> The RasterOp enum -(CopyROP, -OrROP, -XorROP, -NotAndROP, -EraseROP, -NotCopyROP, -NotOrROP, -NotXorROP, -AndROP, NotEraseROP, -NotROP, -ClearROP, -SetROP, -NopROP, -AndNotROP, -OrNotROP, -NandROP, -NorROP, LastROP) -is now part of the Qt namespace class, so if you -use it outside a member function, you'll need to prefix with Qt::. -<p> <h3><a name="QPicture">QPicture</a></h3> -<p> <p>The binary storage format of <a href="qpicture.html">QPicture</a> is changed, but the Qt 2.x -QPicture class can both read and write Qt 1.x format QPictures. No -special handling is required for reading; QPicture will automatically -detect the version number. In order to write a Qt 1.x format QPicture, -set the formatVersion parameter to 1 in the QPicture constructor. -<p> <p>For writing Qt 1.x format QPictures, the compatibility issues of <a -href="#QDataStream">QDataStream</a> applies. -<p> <p>It is safe to try to read a QPicture file generated with Qt 2.x -(without formatVersion set to 1) with a program compiled with Qt -1.x. The program will not crash, it will just issue the warning -"QPicture::play: Incompatible version 2.x" and refuse to load the -picture. -<p> <h3><a name="QPoint">QPoint, <a href="qpointarray.html">QPointArray</a>, <a href="qsize.html">QSize</a> and <a href="qrect.html">QRect</a></a></h3> -<p> <p>The basic coordinate datatype in these classes, QCOORD, is now 32 -bit (int) instead of a 16 bit (short). The const values QCOORD_MIN and -QCOORD_MAX have changed accordingly. -<p> <p>QPointArray is now actually, not only seemingly, a QArray of <a href="qpoint.html">QPoint</a> -objects. The semi-internal workaround classes QPointData and QPointVal -are removed since they are no longer needed; QPoint is used directly -instead. The function <pre> QPointArray::shortPoints()</pre> - -provides the point array converted to short (16bit) coordinates for -use with external functions that demand that format. -<p> <h3><a name="QImage">QImage</a></h3> -<p> <a href="qimage.html">QImage</a> uses QRgb for the colors - see <a href="#QRgb">the changes to that</a>. -<p> <h3><a name="QPixmap">QPixmap</a></h3> -<p> <pre> QPixmap::convertToImage()</pre> - with bitmaps now guarantees that color0 pixels -become color(0) in the resulting QImage. If you worked around the lack of -this, you may be able to simplify your code. If you made assumptions -about the previous undefined behavior, the symptom will be inverted -bitmaps (eg. "inside-out" masks). -<p> <p> -<pre> QPixmap::optimize(TRUE)</pre> - -is replaced by -<pre> QPixmap::setOptimization(QPixmap::NormalOptim)</pre> - -or -<pre> QPixmap::setOptimization(QPixmap::BestOptim)</pre> - -- see the documentation -to choose which is best for your application. NormalOptim is most like -the Qt 1.x "TRUE" optimization. -<p> <h3><a name="QMenuData">QMenuData / <a href="qpopupmenu.html">QPopupMenu</a></a></h3> -<p> In Qt 1.x, new menu items were assigned either an application-wide -unique identifier or an identifier equal to the index of the item, depending on the -<a href="qmenudata.html#insertItem">insertItem(...)</a> function used. -In Qt 2.x this confusing -situation has been cleaned up: generated identifiers are always -unique across the entire application. -<p> If your code depends on generated ids -being equal to the item's index, a quick fix is to use -<pre> QMenuData::indexOf(int id)</pre> - -in the handling function instead. You may alternatively pass -<pre> QMenuData::count()</pre> - -as identifier when you insert the items. -<p> Furthermore, QPopupMenus can (and should!) be created with a parent -widget now, for example the main window that is used to display the -popup. This way, the popup will automatically be destroyed together -with its main window. Otherwise you'll have to take care of the -ownership manually. -<p> QPopupMenus are also reusable in 2.x. They may occur in different -locations within one menu structure or be used as both a menubar -drop-down and as a context popup-menu. This should make it possible to -significantly simplify many applications. -<p> Last but not least, <a href="qpopupmenu.html">QPopupMenu</a> no longer inherits QTableView. Instead, -it directly inherits <a href="qframe.html">QFrame</a>. -<p> <h3><a name="QValidator">QValidator (<a href="qlineedit.html">QLineEdit</a>, <a href="qcombobox.html">QComboBox</a>, <a href="qspinbox.html">QSpinBox</a>) </a></h3> -<p> <pre> QValidator::validate(...)</pre> - -and -<pre> QValidator::fixup( <a href="qstring.html">QString</a> & )</pre> - -are now const -functions. If your subclass reimplements validate() as a -non-const function, -you will get a compile error (validate was pure virtual). -<p> In QLineEdit, QComboBox, and QSpinBox, -setValidator(...) now takes a const pointer to a <a href="qvalidator.html">QValidator</a>, and -validator() returns a const pointer. This change highlights the fact -that the widgets do not take the ownership of the validator (a validator is -a <a href="qobject.html">QObject</a> on its own, with its own parent - you can easily set the same validator -object on many different widgets), so changing the state of -such an object or deleting it is very likely a bug. -<p> <h3><a name="QFile">QFile, <a href="qfileinfo.html">QFileInfo</a>, <a href="qdir.html">QDir</a></a></h3> -<p> File and directory names are now always Unicode strings (ie. <a href="qstring.html">QString</a>). If you used QString -in the past for the simplicity it offers, you'll probably have little consequence. However, -if you pass filenames to system functions rather than using Qt functions (eg. if you use the -Unix <tt>unlink()</tt> function rather than <tt>QFile::remove()</tt>, your code will probably -only work for Latin1 locales (eg. Western Europe, the U.S.). To ensure your code will support -filenames in other locales, either use the Qt functions, or convert the filenames via -<pre> QFile::encodeFilename()</pre> - and <pre> QFile::decodeFilename()</pre> - - but do it -<em>just</em> as you call the system function - code that mixes encoded and unencoded filenames -is very error prone. See the comments in QString, such as regarding QT_NO_ASCII_CAST that -can help find potential problems. -<p> <h3><a name="QFontMetrics">QFontMetrics</a></h3> -<p> boundingRect(char) is replaced by -boundingRect(<a href="qchar.html">QChar</a>), but since -char auto-converts to QChar, you're not likely to run into problems -with this. -<p> <h3><a name="QWindow">QWindow</a></h3> -<p> This class (which was just <a href="qwidget.html">QWidget</a> under a different name) has been -removed. If you used it, do a global search-and-replace of the word -"QWindow" with "QWidget". -<p> <h3><a name="QEvent">QEvent</a></h3> -<p> <p> The global #define macros in qevent.h have been replaced by an -enum in <a href="qevent.html">QEvent</a>. Use e.g. QEvent::Paint instead of Event_Paint. Same -for all of: -Event_None, -Event_Timer, -Event_MouseButtonPress, -Event_MouseButtonRelease, -Event_MouseButtonDblClick, -Event_MouseMove, -Event_KeyPress, -Event_KeyRelease, -Event_FocusIn, -Event_FocusOut, -Event_Enter, -Event_Leave, -Event_Paint, -Event_Move, -Event_Resize, -Event_Create, -Event_Destroy, -Event_Show, -Event_Hide, -Event_Close, -Event_Quit, -Event_Accel, -Event_Clipboard, -Event_SockAct, -Event_DragEnter, -Event_DragMove, -Event_DragLeave, -Event_Drop, -Event_DragResponse, -Event_ChildInserted, -Event_ChildRemoved, -Event_LayoutHint, -Event_ActivateControl, -Event_DeactivateControl, -and -Event_User. -<p> <p> The Q_*_EVENT macros in qevent.h have been deleted. Use an -explicit cast instead. The macros were: -Q_TIMER_EVENT, -Q_MOUSE_EVENT, -Q_KEY_EVENT, -Q_FOCUS_EVENT, -Q_PAINT_EVENT, -Q_MOVE_EVENT, -Q_RESIZE_EVENT, -Q_CLOSE_EVENT, -Q_SHOW_EVENT, -Q_HIDE_EVENT, -and -Q_CUSTOM_EVENT. -<p> <p> QChildEvents are now sent for all QObjects, not just QWidgets. -You may need to add extra checking if you use a <a href="qchildevent.html">QChildEvent</a> without -much testing of its values. -<p> <h3>All the removed functions</h3> -<p> All <a href="removed20.html">these functions</a> have been removed in -Qt 2.x. Most are simply cases where "const char*" has changed to -"const <a href="qstring.html">QString</a>&", or when an enumeration type has moved into the Qt:: -namespace (which, technically, is a new name, but your code will -compile just the same anyway). This list is provided for completeness. -<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>Qt 3.3.8</div> -</table></div></address></body> -</html> |