diff options
Diffstat (limited to 'doc/src/tutorials/widgets-tutorial.qdoc')
| -rw-r--r-- | doc/src/tutorials/widgets-tutorial.qdoc | 141 |
1 files changed, 72 insertions, 69 deletions
diff --git a/doc/src/tutorials/widgets-tutorial.qdoc b/doc/src/tutorials/widgets-tutorial.qdoc index 2b04035d32..2b5f8cce25 100644 --- a/doc/src/tutorials/widgets-tutorial.qdoc +++ b/doc/src/tutorials/widgets-tutorial.qdoc @@ -45,84 +45,97 @@ \brief This tutorial covers basic usage of widgets and layouts, showing how they are used to build GUI applications. - \startpage {index.html}{Qt Reference Documentation} - \contentspage Tutorials - \nextpage {tutorials/widgets/toplevel}{Creating a Window} - - \section1 Introduction - Widgets are the basic building blocks of graphical user interface (GUI) - applications made with Qt. Each GUI component, such as a button, label or - text editor, is a widget and can be placed within an existing user - interface or displayed as an independent window. Each type of component - is provided by a particular subclass of QWidget, which is itself a - subclass of QObject. - - QWidget is not an abstract class; it can be used as a container for other - widgets, and can be subclassed with minimal effort to create custom - widgets. It is most often used to create windows in which other widgets - are placed. - - As with \l{QObject}s, widgets can be created with parent objects to - indicate ownership, ensuring that objects are deleted when they are no - longer used. With widgets, these parent-child relationships have an - additional meaning: each child is displayed within the screen area - occupied by its parent. This means that, when a window is deleted, all - the widgets it contains are automatically deleted. + Widgets are the basic building blocks for graphical user interface + (GUI) applications built with Qt. Each GUI component (e.g. + buttons, labels, text editor) is a \l{QWidget}{widget} that is + placed somewhere within a user interface window, or is displayed + as an independent window. Each type of widge is provided by a + subclass of QWidget, which is itself a subclass of QObject. + + QWidget is not an abstract class. It can be used as a container + for other widgets, and it can be subclassed with minimal effort to + create new, custom widgets. QWidget is often used to create a + window inside which other \l{QWidget}s are placed. + + As with \l{QObject}s, \l{QWidget}s can be created with parent + objects to indicate ownership, ensuring that objects are deleted + when they are no longer used. With widgets, these parent-child + relationships have an additional meaning: Each child widget is + displayed within the screen area occupied by its parent widget. + This means that when you delete a window widget, all the child + widgets it contains are also deleted. \section1 Writing a main Function - Many of the GUI examples in Qt follow the pattern of having a \c{main.cpp} - file containing code to initialize the application, and a number of other - source and header files containing the application logic and custom GUI - components. + Many of the GUI examples provided with Qt follow the pattern of + having a \c{main.cpp} file, which contains the standard code to + initialize the application, plus any number of other source/header + files that contain the application logic and custom GUI components. - A typical \c main() function, written in \c{main.cpp}, looks like this: + A typical \c main() function in \c{main.cpp} looks like this: \snippet doc/src/snippets/widgets-tutorial/template.cpp main.cpp body - We first construct a QApplication object which is configured using any - arguments passed in from the command line. After any widgets have been - created and shown, we call QApplication::exec() to start Qt's event loop. - Control passes to Qt until this function returns, at which point we return - the value we obtain from this function. + First, a QApplication object is constructed, which can be + configured with arguments passed in from the command line. After + the widgets have been created and shown, QApplication::exec() is + called to start Qt's event loop. Control passes to Qt until this + function returns. Finally, \c{main()} returns the value returned + by QApplication::exec(). - In each part of this tutorial, we provide an example that is written - entirely within a \c main() function. In more sophisticated examples, the - code to set up widgets and layouts is written in other parts of the - example. For example, the GUI for a main window may be set up in the - constructor of a QMainWindow subclass. + \section1 Simple widget examples + + Each of theses simple widget examples is written entirely within + the \c main() function. + + \list + \o \l {tutorials/widgets/toplevel} {Creating a window} + + \o \l {tutorials/widgets/childwidget} {Creating child widgets} + + \o \l {tutorials/widgets/windowlayout} {Using layouts} + + \o \l {tutorials/widgets/nestedlayouts} {Nested layouts} + \endlist + + \section1 Real world widget examples - The \l{Widgets examples} are a good place to look for - more complex and complete examples and applications. + In these \l{Widget examples} {more advanced examples}, the code + that creates the widgets and layouts is stored in other files. For + example, the GUI for a main window may be created in the + constructor of a QMainWindow subclass. - \section1 Building Examples and Tutorials + \section1 Building The Examples - If you obtained a binary package of Qt or compiled it yourself, the - examples described in this tutorial should already be ready to run. - However, if you may wish to modify them and recompile them, you need to - perform the following steps: + If you installed a binary package to get Qt, or if you compiled Qt + yourself, the examples described in this tutorial should already + be built and ready to run. If you wish to modify and recompile + them, follow these steps: \list 1 - \o At the command line, enter the directory containing the example you - wish to recompile. - \o Type \c qmake and press \key{Return}. If this doesn't work, make sure - that the executable is on your path, or enter its full location. - \o On Linux/Unix and Mac OS X, type \c make and press \key{Return}; - on Windows with Visual Studio, type \c nmake and press \key{Return}. + + \o From a command prompt, enter the directory containing the + example you have modified. + + \o Type \c qmake and press \key{Return}. If this doesn't work, + make sure that the executable is on your path, or enter its + full location. + + \o On Linux/Unix and Mac OS X, type \c make and press + \key{Return}; on Windows with Visual Studio, type \c nmake and + press \key{Return}. + \endlist - An executable file should have been created within the current directory. - On Windows, this file may be located within a \c debug or \c release - subdirectory. You can run this file to see the example code at work. + An executable file is created in the current directory. On + Windows, this file may be located in a \c debug or \c release + subdirectory. You can run this executable to see the example code + at work. */ /*! - \page widgets-tutorial-toplevel.html - \contentspage {Widgets Tutorial}{Contents} - \previouspage {Widgets Tutorial} - \nextpage {Widgets Tutorial - Child Widgets} \example tutorials/widgets/toplevel \title Widgets Tutorial - Creating a Window @@ -151,13 +164,10 @@ To create a real GUI, we need to place widgets inside the window. To do this, we pass a QWidget instance to a widget's constructor, as we will demonstrate in the next part of this tutorial. + */ /*! - \page widgets-tutorial-childwidget.html - \contentspage {Widgets Tutorial}{Contents} - \previouspage {Widgets Tutorial - Creating a Window} - \nextpage {Widgets Tutorial - Using Layouts} \example tutorials/widgets/childwidget \title Widgets Tutorial - Child Widgets @@ -185,10 +195,6 @@ */ /*! - \page widgets-tutorial-windowlayout.html - \contentspage {Widgets Tutorial}{Contents} - \previouspage {Widgets Tutorial - Child Widgets} - \nextpage {Widgets Tutorial - Nested Layouts} \example tutorials/widgets/windowlayout \title Widgets Tutorial - Using Layouts @@ -228,9 +234,6 @@ */ /*! - \page widgets-tutorial-nestedlayouts.html - \contentspage {Widgets Tutorial}{Contents} - \previouspage {Widgets Tutorial - Using Layouts} \example tutorials/widgets/nestedlayouts \title Widgets Tutorial - Nested Layouts |