《C++ GUI Programming with Qt 4, Second Edition》读书笔记2

Chapter 1 Getting Started / Making Connections

 

signal/slot机制

本小节讲述的是QT特有的signal/slot机制。
代码如下：

1:  #include <QApplication>

2:  #include <QPushButton>

3:   

4:  int main(int argc, char *argv[])

5:  {

6:      QApplication app(argc, argv);

7:  //    QPushButton *button = new QPushButton("Quit");

8:  //    QObject::connect(button, SIGNAL(clicked()), &app, SLOT(quit()));

9:  //    button->show();

10:   

11:      QPushButton button("Quit");

12:      QObject::connect(&button, SIGNAL(clicked()), &app, SLOT(quit()));

13:      button.show();

14:   

15:      return app.exec();

16:  }

其中，第12行是事件绑定和处理的核心代码。

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.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
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QPushButton提供的signal

Class	SIGNAL	说明
QPushButton	没有
QAbstractButton	clicked pressed released toggled	点击鼠标或者按下快捷键 按钮被按下 按钮被松开 按钮状态变化
QWidget	customContextMenuRequested
QObject	destroyed

 

QApplication提供的SLOT

Class	SLOT	说明
QApplication	aboutQt autoMaximizeThreshold autoSipEnabled closeAllWindows setAutoautoMaximizeThreshold setAutoSipEnabled setStyleSheet	only for Windows CE only for Windows CE only for Windows CE only for Windows CE
QCoreApplication	quit
QObject	deleteLater

 

后续工作

写个例子来使用pressed/released/toggled信号