How to Use QPushButton: Difference between revisions

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[[Category:Developing with Qt::General]]<br />[[Category:HowTo]]<br />[[Category:Snippets]]<br />[[Category:Tutorial]]
[[Category:Developing with Qt::General]]
[[Category:HowTo]]
[[Category:Snippets]]
[[Category:Tutorial]]


[toc align_right="yes" depth="3"]
[toc align_right="yes" depth="3"]


'''English''' [[How_to_Use_QPushButton_Bulgarian|Български]] [[How_to_Use_QPushButton_Spanish|Spanish]] [[How_to_Use_QPushButton_SimplifiedChinese|简体中文]] [[How_to_Use_QPushButton_Greek|Ελληνικά]]<br />[[How_to_Use_QPushButton_Russian|Русский]][[How_to_Use_QPushButton_Persian|فارسی]]
'''English''' [[How_to_Use_QPushButton_Bulgarian|Български]] [[How_to_Use_QPushButton_Spanish|Spanish]] [[How_to_Use_QPushButton_SimplifiedChinese|简体中文]] [[How_to_Use_QPushButton_Greek|Ελληνικά]]
[[How_to_Use_QPushButton_Russian|Русский]][[How_to_Use_QPushButton_Persian|فارسی]]


= How to Use QPushButton =
= How to Use QPushButton =
Line 58: Line 62:
=== mainwindow.h ===
=== mainwindow.h ===


</code><br />#ifndef MAINWINDOW_H<br />#define MAINWINDOW_H
</code>
#ifndef MAINWINDOW_H
#define MAINWINDOW_H


#include <QtGui/QMainWindow><br />#include <QtGui/QPushButton><br />//#include <QMainWindow>//For Qt5<br />//#include <QPushButton>//For Qt5
#include <QtGui/QMainWindow>
#include <QtGui/QPushButton>
//#include <QMainWindow>//For Qt5
//#include <QPushButton>//For Qt5


namespace Ui {<br /> class MainWindow;<br />}
namespace Ui {
class MainWindow;
}


class MainWindow : public QMainWindow<br />{<br /> Q_OBJECT
class MainWindow : public QMainWindow
{
Q_OBJECT


public:<br /> explicit MainWindow(QWidget *parent = 0);
public:
explicit MainWindow(QWidget *parent = 0);


private slots:<br /> void handleButton();
private slots:
void handleButton();


private:<br /> QPushButton *m_button;<br />};
private:
QPushButton *m_button;
};


#endif // MAINWINDOW_H<br /><code>
#endif // MAINWINDOW_H
<code>


=== mainwindow.cpp ===
=== mainwindow.cpp ===


</code><br />#include "mainwindow.h"
</code>
#include "mainwindow.h"


#include <QtCore/QCoreApplication><br />//#include <QCoreApplication>//For Qt5
#include <QtCore/QCoreApplication>
//#include <QCoreApplication>//For Qt5


MainWindow::MainWindow(QWidget *parent)<br /> : QMainWindow(parent)<br />{<br /> // Create the button, make "this" the parent<br /> m_button = new QPushButton("My Button", this);<br /> // set size and location of the button<br /> m_button->setGeometry(QRect(QPoint(100, 100),<br /> QSize(200, 50)));
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
// Create the button, make "this" the parent
m_button = new QPushButton("My Button", this);
// set size and location of the button
m_button->setGeometry(QRect(QPoint(100, 100),
QSize(200, 50)));


// Connect button signal to appropriate slot<br /> connect(m_button, SIGNAL (released()), this, SLOT (handleButton()));<br />}
// Connect button signal to appropriate slot
connect(m_button, SIGNAL (released()), this, SLOT (handleButton()));
}


void MainWindow::handleButton()<br />{<br /> // change the text<br /> m_button->setText("Example");<br /> // resize button<br /> m_button->resize(100,100);<br />}<br /><code>
void MainWindow::handleButton()
{
// change the text
m_button->setText("Example");
// resize button
m_button->resize(100,100);
}
<code>


=== main.cpp ===
=== main.cpp ===


</code><br />#include "mainwindow.h"
</code>
#include "mainwindow.h"


#include <QtGui/QApplication><br />//#include <QApplication> //For Qt5
#include <QtGui/QApplication>
//#include <QApplication> //For Qt5


int main(int argc, char *argv[])<br />{<br /> QApplication app(argc, argv);
int main(int argc, char *argv[])
{
QApplication app(argc, argv);


MainWindow mainWindow;<br /> mainWindow.showMaximized();<br /> return app.exec();<br />}
MainWindow mainWindow;
mainWindow.showMaximized();
return app.exec();
}


<code>
<code>

Revision as of 08:34, 25 February 2015


[toc align_right="yes" depth="3"]

English Български Spanish 简体中文 Ελληνικά Русскийفارسی

How to Use QPushButton

QPushButton Overview

Using "QPushButton":http://doc.qt.io/qt-5.0/qtwidgets/qpushbutton.html developers can create and handle buttons. This class is easy to use and customize so it is among the most useful classes in Qt. In general the button displays text but an icon can also be displayed.

QPushButton inherits "QAbstractButton":http://doc.qt.io/qt-5.0/qtwidgets/qabstractbutton.html which inherits "QWidget":http://doc.qt.io/qt-5.0/qtwidgets/qwidget.html.

Signals

Inherited from QAbstractButton

  • void clicked ( bool checked = false )
  • void pressed ()
  • void released ()
  • void toggled ( bool checked )

Inherited from QWidget

  • void customContextMenuRequested ( const QPoint & pos )

Inherited from QObject

  • void destroyed ( QObject * obj = 0 )

Basic Usage

Text

The text of QPushButton can be set upon creation or using "setText()":http://doc.qt.io/qt-5.0/qtwidgets/qabstractbutton.html#text-prop. To get the current text of the button use "text()":http://doc.qt.io/qt-5.0/qtwidgets/qabstractbutton.html#text-prop.

Icon

The icon of QPushButton can also be set upon creation. After creation the icon can be changed using "setIcon()":http://doc.qt.io/qt-5.0/qtwidgets/qabstractbutton.html#icon-prop To get the current icon of the button use "icon()":http://doc.qt.io/qt-5.0/qtwidgets/qabstractbutton.html#icon-prop

Set Position and Size

To set the position and the size of the button use "setGeometry()":http://doc.qt.io/qt-5.0/qtwidgets/qwidget.html#geometry-prop. If you want just to modify the size of the button use "resize()":http://doc.qt.io/qt-5.0/qtwidgets/qwidget.html#size-prop.

Handle Button

QPushButton emits signals if an event occurs. To handle the button connect its appropriate signal to a slot: 

connect(m_button, SIGNAL (released()),this, SLOT (handleButton()));<code>

== Example ==

The following simple code snippet shows how to create and use QPushButton. It has been tested on Qt Symbian Simulator.

An instance of QPushButton is created. Signal '''released()''' is connected to slot '''handleButton()''' which changes the text and the size of the button.

=== mainwindow.h ===
  1. ifndef MAINWINDOW_H
  2. define MAINWINDOW_H
  1. include <QtGui/QMainWindow>
  2. include <QtGui/QPushButton>

//#include <QMainWindow>//For Qt5 //#include <QPushButton>//For Qt5

namespace Ui { 

class MainWindow;

}

class MainWindow : public QMainWindow { 

Q_OBJECT

public: 

explicit MainWindow(QWidget *parent = 0);

private slots: 

void handleButton();

private: 

QPushButton *m_button;

};

  1. endif // MAINWINDOW_H
=== mainwindow.cpp ===
  1. include "mainwindow.h"
  1. include <QtCore/QCoreApplication>

//#include <QCoreApplication>//For Qt5

MainWindow::MainWindow(QWidget *parent) 

: QMainWindow(parent)

{ 

// Create the button, make "this" the parent
m_button = new QPushButton("My Button", this);
// set size and location of the button
m_button->setGeometry(QRect(QPoint(100, 100),
QSize(200, 50)));

// Connect button signal to appropriate slot 

connect(m_button, SIGNAL (released()), this, SLOT (handleButton()));

}

void MainWindow::handleButton() { 

// change the text
m_button->setText("Example");
// resize button
m_button->resize(100,100);

} 

=== main.cpp ===
  1. include "mainwindow.h"
  1. include <QtGui/QApplication>

//#include <QApplication> //For Qt5

int main(int argc, char *argv[]) { 

QApplication app(argc, argv);

MainWindow mainWindow; 

mainWindow.showMaximized();
return app.exec();

}

See also

"Qt Buttons":http://developer.qt.nokia.com/wiki/Qt_Buttons

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