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diff --git a/doc/src/widgets/widgets-tutorial.qdoc b/doc/src/widgets/widgets-tutorial.qdoc deleted file mode 100644 index 735a7ebc54..0000000000 --- a/doc/src/widgets/widgets-tutorial.qdoc +++ /dev/null @@ -1,249 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** GNU Free Documentation License -** Alternatively, this file may be used under the terms of the GNU Free -** Documentation License version 1.3 as published by the Free Software -** Foundation and appearing in the file included in the packaging of -** this file. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms -** and conditions contained in a signed written agreement between you -** and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \page widgets-tutorial.html - \ingroup tutorials - \title Widgets Tutorial - \brief This tutorial covers basic usage of widgets and layouts, showing how - they are used to build GUI applications. - - \section1 Introduction - - 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 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 in \c{main.cpp} looks like this: - - \snippet doc/src/snippets/widgets-tutorial/template.cpp main.cpp body - - 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(). - - \section1 Simple widget examples - - Each of theses simple widget examples is written entirely within - the \c main() function. - - \list - \li \l {tutorials/widgets/toplevel} {Creating a window} - - \li \l {tutorials/widgets/childwidget} {Creating child widgets} - - \li \l {tutorials/widgets/windowlayout} {Using layouts} - - \li \l {tutorials/widgets/nestedlayouts} {Nested layouts} - \endlist - - \section1 Real world widget examples - - 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 The Examples - - 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 - - \li From a command prompt, enter the directory containing the - example you have modified. - - \li 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. - - \li 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 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. -*/ - -/*! - \example tutorials/widgets/toplevel - \title Widgets Tutorial - Creating a Window - - If a widget is created without a parent, it is treated as a window, or - \e{top-level widget}, when it is shown. Since it has no parent object to - ensure that it is deleted when no longer needed, it is up to the - developer to keep track of the top-level widgets in an application. - - In the following example, we use QWidget to create and show a window with - a default size: - - \div {class="qt-code"} - \table - \row - \li \snippet tutorials/widgets/toplevel/main.cpp main program - \li \inlineimage widgets-tutorial-toplevel.png - \endtable - \enddiv - - 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. - -*/ - -/*! - \example tutorials/widgets/childwidget - \title Widgets Tutorial - Child Widgets - - We can add a child widget to the window created in the previous example by - passing \c window as the parent to its constructor. In this case, we add a - button to the window and place it in a specific location: - - \div {class="qt-code"} - \table - \row - \li \snippet tutorials/widgets/childwidget/main.cpp main program - \li \inlineimage widgets-tutorial-childwidget.png - \endtable - \enddiv - - The button is now a child of the window and will be deleted when the - window is destroyed. Note that hiding or closing the window does not - automatically destroy it. It will be destroyed when the example exits. -*/ - -/*! - \example tutorials/widgets/windowlayout - \title Widgets Tutorial - Using Layouts - - Usually, child widgets are arranged inside a window using layout objects - rather than by specifying positions and sizes explicitly. Here, we - construct a label and line edit widget that we would like to arrange - side-by-side. - - \div {class="qt-code"} - \table - \row - \li \snippet tutorials/widgets/windowlayout/main.cpp main program - \li \inlineimage widgets-tutorial-windowlayout.png - \endtable - \enddiv - - The \c layout object we construct manages the positions and sizes of - widgets supplied to it with the \l{QHBoxLayout::}{addWidget()} function. - The layout itself is supplied to the window itself in the call to - \l{QWidget::}{setLayout()}. Layouts are only visible through the effects - they have on the widgets (and other layouts) they are responsible for - managing. - - In the example above, the ownership of each widget is not immediately - clear. Since we construct the widgets and the layout without parent - objects, we would expect to see an empty window and two separate windows - containing a label and a line edit. However, when we tell the layout to - manage the label and line edit and set the layout on the window, both the - widgets and the layout itself are ''reparented'' to become children of - the window. -*/ - -/*! - \example tutorials/widgets/nestedlayouts - \title Widgets Tutorial - Nested Layouts - - Just as widgets can contain other widgets, layouts can be used to provide - different levels of grouping for widgets. Here, we want to display a - label alongside a line edit at the top of a window, above a table view - showing the results of a query. - - We achieve this by creating two layouts: \c{queryLayout} is a QHBoxLayout - that contains QLabel and QLineEdit widgets placed side-by-side; - \c{mainLayout} is a QVBoxLayout that contains \c{queryLayout} and a - QTableView arranged vertically. - - \div {class="qt-code"} - \table - \row - \li \snippet tutorials/widgets/nestedlayouts/main.cpp first part - \snippet tutorials/widgets/nestedlayouts/main.cpp last part - \li \inlineimage widgets-tutorial-nestedlayouts.png - \endtable - \enddiv - - Note that we call the \c{mainLayout}'s \l{QBoxLayout::}{addLayout()} - function to insert the \c{queryLayout} above the \c{resultView} table. - - We have omitted the code that sets up the model containing the data shown - by the QTableView widget, \c resultView. For completeness, we show this below. - - As well as QHBoxLayout and QVBoxLayout, Qt also provides QGridLayout - and QFormLayout classes to help with more complex user interfaces. - These can be seen if you run \l{Qt Designer}. - - \section1 Setting up the Model - - In the code above, we did not show where the table's data came from - because we wanted to concentrate on the use of layouts. Here, we see - that the model holds a number of items corresponding to rows, each of - which is set up to contain data for two columns. - - \snippet tutorials/widgets/nestedlayouts/main.cpp set up the model - - The use of models and views is covered in the - \l{Item Views Examples} and in the \l{Model/View Programming} overview. -*/ |