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diff --git a/doc/man/man3/qguardedptr.3qt b/doc/man/man3/qguardedptr.3qt deleted file mode 100644 index 11f362d4c..000000000 --- a/doc/man/man3/qguardedptr.3qt +++ /dev/null @@ -1,148 +0,0 @@ -'\" t -.TH QGuardedPtr 3qt "2 February 2007" "Trolltech AS" \" -*- nroff -*- -.\" Copyright 1992-2007 Trolltech ASA. All rights reserved. See the -.\" license file included in the distribution for a complete license -.\" statement. -.\" -.ad l -.nh -.SH NAME -QGuardedPtr \- Template class that provides guarded pointers to QObjects -.SH SYNOPSIS -\fC#include <ntqguardedptr.h>\fR -.PP -.SS "Public Members" -.in +1c -.ti -1c -.BI "\fBQGuardedPtr\fR ()" -.br -.ti -1c -.BI "\fBQGuardedPtr\fR ( T * p )" -.br -.ti -1c -.BI "\fBQGuardedPtr\fR ( const QGuardedPtr<T> & p )" -.br -.ti -1c -.BI "\fB~QGuardedPtr\fR ()" -.br -.ti -1c -.BI "QGuardedPtr<T> & \fBoperator=\fR ( const QGuardedPtr<T> & p )" -.br -.ti -1c -.BI "QGuardedPtr<T> & \fBoperator=\fR ( T * p )" -.br -.ti -1c -.BI "bool \fBoperator==\fR ( const QGuardedPtr<T> & p ) const" -.br -.ti -1c -.BI "bool \fBoperator!=\fR ( const QGuardedPtr<T> & p ) const" -.br -.ti -1c -.BI "bool \fBisNull\fR () const" -.br -.ti -1c -.BI "T * \fBoperator->\fR () const" -.br -.ti -1c -.BI "T & \fBoperator*\fR () const" -.br -.ti -1c -.BI "\fBoperator T *\fR () const" -.br -.in -1c -.SH DESCRIPTION -The QGuardedPtr class is a template class that provides guarded pointers to QObjects. -.PP -A guarded pointer, \fCQGuardedPtr<X>\fR, behaves like a normal C++ pointer \fCX*\fR, except that it is automatically set to 0 when the referenced object is destroyed (unlike normal C++ pointers, which become "dangling pointers" in such cases). \fCX\fR must be a subclass of QObject. -.PP -Guarded pointers are useful whenever you need to store a pointer to a QObject that is owned by someone else and therefore might be destroyed while you still hold a reference to it. You can safely test the pointer for validity. -.PP -Example: -.PP -.nf -.br - QGuardedPtr<QLabel> label = new QLabel( 0, "label" ); -.br - label->setText( "I like guarded pointers" ); -.br -.br - delete (QLabel*) label; // simulate somebody destroying the label -.br -.br - if ( label) -.br - label->show(); -.br - else -.br - tqDebug("The label has been destroyed"); -.br -.fi -.PP -The program will output \fCThe label has been destroyed\fR rather than dereferencing an invalid address in \fClabel->show()\fR. -.PP -The functions and operators available with a QGuardedPtr are the same as those available with a normal unguarded pointer, except the pointer arithmetic operators (++, --, -, and +), which are normally used only with arrays of objects. Use them like normal pointers and you will not need to read this class documentation. -.PP -For creating guarded pointers, you can construct or assign to them from an X* or from another guarded pointer of the same type. You can compare them with each other using operator==() and operator!=(), or test for 0 with isNull(). And you can dereference them using either the \fC*x\fR or the \fCx->member\fR notation. -.PP -A guarded pointer will automatically cast to an X*, so you can freely mix guarded and unguarded pointers. This means that if you have a QGuardedPtr<QWidget>, you can pass it to a function that requires a QWidget*. For this reason, it is of little value to declare functions to take a QGuardedPtr as a parameter; just use normal pointers. Use a QGuardedPtr when you are storing a pointer over time. -.PP -Note again that class \fIX\fR must inherit QObject, or a compilation or link error will result. -.PP -See also Object Model. -.SH MEMBER FUNCTION DOCUMENTATION -.SH "QGuardedPtr::QGuardedPtr ()" -Constructs a 0 guarded pointer. -.PP -See also isNull(). -.SH "QGuardedPtr::QGuardedPtr ( T * p )" -Constructs a guarded pointer that points to same object as \fIp\fR points to. -.SH "QGuardedPtr::QGuardedPtr ( const QGuardedPtr<T> & p )" -Copy one guarded pointer from another. The constructed guarded pointer points to the same object that \fIp\fR points to (which may be 0). -.SH "QGuardedPtr::~QGuardedPtr ()" -Destroys the guarded pointer. Just like a normal pointer, destroying a guarded pointer does \fInot\fR destroy the object being pointed to. -.SH "bool QGuardedPtr::isNull () const" -Returns \fCTRUE\fR if the referenced object has been destroyed or if there is no referenced object; otherwise returns FALSE. -.SH "QGuardedPtr::operator T * () const" -Cast operator; implements pointer semantics. Because of this function you can pass a QGuardedPtr<X> to a function where an X* is required. -.SH "bool QGuardedPtr::operator!= ( const QGuardedPtr<T> & p ) const" -Inequality operator; implements pointer semantics, the negation of operator==(). Returns TRUE if \fIp\fR and this guarded pointer are not pointing to the same object; otherwise returns FALSE. -.SH "T & QGuardedPtr::operator* () const" -Dereference operator; implements pointer semantics. Just use this operator as you would with a normal C++ pointer. -.SH "T * QGuardedPtr::operator-> () const" -Overloaded arrow operator; implements pointer semantics. Just use this operator as you would with a normal C++ pointer. -.SH "QGuardedPtr<T> & QGuardedPtr::operator= ( const QGuardedPtr<T> & p )" -Assignment operator. This guarded pointer then points to the same object as \fIp\fR points to. -.SH "QGuardedPtr<T> & QGuardedPtr::operator= ( T * p )" -This is an overloaded member function, provided for convenience. It behaves essentially like the above function. -.PP -Assignment operator. This guarded pointer then points to the same object as \fIp\fR points to. -.SH "bool QGuardedPtr::operator== ( const QGuardedPtr<T> & p ) const" -Equality operator; implements traditional pointer semantics. Returns TRUE if both \fIp\fR and this guarded pointer are 0, or if both \fIp\fR and this pointer point to the same object; otherwise returns FALSE. -.PP -See also operator!=(). - -.SH "SEE ALSO" -.BR http://doc.trolltech.com/ntqguardedptr.html -.BR http://www.trolltech.com/faq/tech.html -.SH COPYRIGHT -Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the -license file included in the distribution for a complete license -statement. -.SH AUTHOR -Generated automatically from the source code. -.SH BUGS -If you find a bug in Qt, please report it as described in -.BR http://doc.trolltech.com/bughowto.html . -Good bug reports help us to help you. Thank you. -.P -The definitive Qt documentation is provided in HTML format; it is -located at $QTDIR/doc/html and can be read using Qt Assistant or with -a web browser. This man page is provided as a convenience for those -users who prefer man pages, although this format is not officially -supported by Trolltech. -.P -If you find errors in this manual page, please report them to -.BR qt-bugs@trolltech.com . -Please include the name of the manual page (qguardedptr.3qt) and the Qt -version (3.3.8). |