qt4.键盘方向键
2016-04-15 11:30
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QT程序设计进阶-事件
Qt事件PS：出现焦点的话，方向键盘是没有进入事件的..
Qt程序是事件驱动的, 程序的每个动作都是由幕后某个事件所触发.
Qt事件的类型很多, 常见的qt的事件如下:
键盘事件: 按键按下和松开.
鼠标事件: 鼠标移动,鼠标按键的按下和松开.
拖放事件: 用鼠标进行拖放.
滚轮事件: 鼠标滚轮滚动.
绘屏事件: 重绘屏幕的某些部分.
定时事件: 定时器到时.
焦点事件: 键盘焦点移动.
进入和离开事件: 鼠标移入widget之内,或是移出.
移动事件: widget的位置改变.
大小改变事件: widget的大小改变.
显示和隐藏事件: widget显示和隐藏.
窗口事件: 窗口是否为当前窗口.
还有一些非常见的qt事件,比如socket事件,剪贴板事件,字体改变,布局改变等等.
Qt 的事件和Qt中的signal不一样. 后者通常用来使用widget, 而前者用来实现 widget.
比如一个按钮, 我们使用这个按钮的时候, 我们只关心他clicked()的signal, 至于这个按钮如何接收处理鼠标事件,再发射这个信号,我们是不用关心的. 但是如果我们要重载一个按钮的时候,我们就要面对event了. 比如我们可以改变它的行为,在鼠标按键按下的时候(mouse press event) 就触发clicked()的signal而不是通常在释放的( mouse release event)时候.
事件起源：
基于事件如何被产生与分发，可以把事件分为三类：
1)Spontaneous 事件
2) Posted 事件
3)Sent 事件
1)Spontaneous 事件,由窗口系统产生，它们被放到系统队列中，通过事件循环逐个处理。
本类事件通常是window system把从系统得到的消息,比如鼠标按键,键盘按键等, 放入系统的消息队列中. Qt事件循环的时候读取这些事件,转化为QEvent,再依次处理.
2)Posted 事件，由Qt或是应用程序产生，它们被Qt组成队列，再通过事件循环处理。
调用QApplication::postEvent()来产生一个posted类型事件.
例如：QWidget::update()函数
当需要重新绘制屏幕时,程序调用update()函数
其实现的原理是new出一个paintEvent,调用 QApplication::postEvent(),将其放入Qt的消息队列中,等待依次被处理.
3)Sent 事件由Qt或是应用程序产生，但它们被直接发送到目标对象。
调用QApplication::sendEvent()函数来产生一个sent类型事件.
sent 类型事件不会放入队列, 而是直接被派发和处理, QWidget::repaint()函数用的就是这种方式.
当我们在main()函数的末尾调用QApplication::exec()时,程序进入了Qt的事件循环
事件循环如下面所示：
while (!exit_was_called)
{
while(!posted_event_queue_is_empty)
{
process_next_posted_event();
}
while(!spontaneous_event_queue_is_empty)
{
process_next_spontaneous_event();
}
while(!posted_event_queue_is_empty)
{
process_next_posted_event();
}
}
事件循环的处理流程：
1)先处理Qt事件队列中的posted事件，直至为空
2)再处理系统消息队列中的spontaneous消息，直至为空
3)在处理系统消息的时候会产生新的Qt posted事件，需要对其再次进行处理
不通过事件循环
sendEvent的事件派发不通过事件循环。QApplication::sendEvent()是通过调用QApplication::notify()，直接进入了事件的派发和处理环节。
Notify
调用QApplication::sendEvent的时候, 消息会立即被处理,是同步的. 实际上QApplication::sendEvent()是通过调用QApplication::notify(), 直接进入了事件的派发和处理环节.所有的事件都最终通过 notify 派发到相应的对象中。
bool QApplication::notify ( QObject * receiver, QEvent * event )
它是通过调用receiver->event(event) 来实现的。
目标接受对象的event方法会自动接受notify传来的event事件
event() 会返回一个布尔值，来告诉调用者是否事件被accept或ignore,
(true表示accept)，从event()返回的布尔值却是用来与QApplication:notify()通讯的
event()函数的处理如下所示：
bool QWidget::event(QEvent *event)
{
switch (e->type()) {
case QEvent::KeyPress:
keyPressEvent((QKeyEvent *)event);
if (!((QKeyEvent *)event)->isAccepted())
return false;
break;
case QEvent::KeyRelease:
keyReleaseEvent((QKeyEvent *)event);
if (!((QKeyEvent *)event)->isAccepted())
return false;
break;
...
}
return true;
}
Close事件有点不同，调用QCloseEvent:ignore()取消了关闭操作，而accept()告诉Qt继续执行正常的关闭操作。为了避免混乱，最好是在closeEvent()的新实现中明确地进行accept()与ignore()的调用：、
void MainWindow::closeEvent(QCloseEvent *event)
{
if (userReallyWantsToQuit()) {
event->accept();
} else {
event->ignore();
}
}
例子：keyPressEvent
在空白窗体页面，重载当前窗体类的keyPressEvent方法，实现按键事件的响应。步骤一：
添加头文件<qevent.h>
在form.cpp中填加void Form1::keyPressEvent（QKeyEvent *k ）
并实现根据不同的键值，执行不同的动作。
步骤二：
添加头文件<qevent.h>
在form.h 中为窗体类form1添加 void keyPressEvent（QKeyEvent *k ）声明；
步骤三：
重新编译工程并运行测试。
void Form1::keyPressEvent( QKeyEvent *k )
{
if(k->key() == Key_Left)
{
qDebug("Left\n");
....
}
else if(k->key() == Key_Right)
{
qDebug("Right\n");
...
}
else QWidget::keyPressEvent(k);
}
在具备子控件的复杂窗体中，重载当前窗体类的keyPressEvent方法，实现按键事件的响应。
步骤一：
添加头文件<qevent.h>
在form.cpp中填加void Form1::keyPressEvent（QKeyEvent *k ）
并实现根据不同的键值，执行不同的动作。
步骤二：
添加头文件<qevent.h>
在form.h 中为窗体类form1添加 void keyPressEvent（QKeyEvent *k ）声明；
步骤三：
在form.cpp中，消除子控件的焦点策略，使能方向及Tab按键功能。
步骤四：
重新编译工程并运行测试。
例如：
pushButton1 = new QPushButton( this, "pushButton1" );
pushButton1->setGeometry( QRect( 200, 150, 111, 41 ) );
pushButton1->setFocusPolicy(QWidget::NoFocus);
void QWidget::setFocusPolicy ( FocusPolicy )
设置这个窗口部件接收键盘焦点的方式。
“focusPolicy”属性保存的是窗口部件接收键盘焦点的策略。
如果窗口部件通过tab来接收键盘焦点，这个策略就是QWidget::TabFocus；
如果窗口部件通过点击来接收键盘焦点，这个策略就是QWidget::ClickFocus；
如果窗口部件上述两种方式都使用，是QWidget::StrongFocus；
如果它不接收焦点（QWidget的默认值），是QWidget::NoFocus。
重载当前窗体类的event方法，实现针对性事件的处理与过滤效果。
步骤一：
在form.cpp中填加bool Form1::event（QEvent *event）
并实现根据不同的键值，执行不同的动作。
步骤二：
在form.h 中为窗体类form1添加 bool event（QEvent *event）声明；
步骤三：
重新编译工程并运行测试。
bool Form1::event(QEvent * event)
{
if (event->type() == QEvent::KeyPress)
{
QKeyEvent *keyEvent = (QKeyEvent *) event;
if (keyEvent->key() == Key_A)
{
qDebug("--cut the Key_A--\n");
return true;
}
}
return QWidget::event(event);
}
实验：
1）用鼠标事件实现鼠标放在按钮上，按钮变大。
2）用按键事件实现方向右和方向左键控制2个窗口
3）用信号与槽机制实现鼠标点击next和back实现控制2个窗口
main.cpp:
[cpp] view
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#include <qapplication.h>
#include "form1.h"
int main( int argc, char ** argv )
{
QApplication a( argc, argv );
Form1 w;
w.show();
a.connect( &a, SIGNAL( lastWindowClosed() ), &a, SLOT( quit() ) );
return a.exec();
}
[cpp] view
plaincopy
#include <qapplication.h>
#include "form1.h"
int main( int argc, char ** argv )
{
QApplication a( argc, argv );
Form1 w;
w.show();
a.connect( &a, SIGNAL( lastWindowClosed() ), &a, SLOT( quit() ) );
return a.exec();
}
[cpp] view
plain copy
#include <qapplication.h>
#include "form1.h"
int main( int argc, char ** argv )
{
QApplication a( argc, argv );
Form1 w;
w.show();
a.connect( &a, SIGNAL( lastWindowClosed() ), &a, SLOT( quit() ) );
return a.exec();
}
form1.cpp
[cpp] view
plaincopy
#include "form1.h"
#include "form2.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form1 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form1::Form1( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form1" );
setMouseTracking (true);
pushButton1_3_2 = new QPushButton( this, "pushButton1_3_2" );
pushButton1_3_2->setGeometry( QRect( 210, 80, 51, 41 ) );
pushButton1_3_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_4_2 = new QPushButton( this, "pushButton1_4_2" );
pushButton1_4_2->setGeometry( QRect( 140, 80, 51, 41 ) );
pushButton1_4_2->setFocusPolicy(QWidget::NoFocus);
pushButton1 = new QPushButton( this, "pushButton1" );
pushButton1->setGeometry( QRect( 70, 20, 51, 41 ) );
pushButton1->setFocusPolicy(QWidget::NoFocus);
pushButton1_3 = new QPushButton( this, "pushButton1_3" );
pushButton1_3->setGeometry( QRect( 210, 20, 51, 41 ) );
pushButton1_3->setFocusPolicy(QWidget::NoFocus);
pushButton1_5 = new QPushButton( this, "pushButton1_5" );
pushButton1_5->setGeometry( QRect( 70, 80, 51, 41 ) );
pushButton1_5->setFocusPolicy(QWidget::NoFocus);
pushButton1_4 = new QPushButton( this, "pushButton1_4" );
pushButton1_4->setGeometry( QRect( 140, 20, 51, 41 ) );
pushButton1_4->setFocusPolicy(QWidget::NoFocus);
pushButton1_2 = new QPushButton( this, "pushButton1_2" );
pushButton1_2->setGeometry( QRect( 280, 20, 51, 41 ) );
pushButton1_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_2_2 = new QPushButton( this, "pushButton1_2_2" );
pushButton1_2_2->setGeometry( QRect( 280, 80, 51, 41 ) );
pushButton1_2_2->setFocusPolicy(QWidget::NoFocus);
pushButton9 = new QPushButton( this, "pushButton9" );
pushButton9->setGeometry( QRect( 340, 160, 70, 30 ) );
pushButton9->setFocusPolicy(QWidget::NoFocus);
languageChange();
resize( QSize(434, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton9, SIGNAL( clicked() ), this, SLOT( next() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form1::~Form1()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form1::languageChange()
{
setCaption( tr( "Form1" ) );
pushButton1_3_2->setText( tr( "7" ) );
pushButton1_4_2->setText( tr( "6" ) );
pushButton1->setText( tr( "1" ) );
pushButton1_3->setText( tr( "3" ) );
pushButton1_5->setText( tr( "5" ) );
pushButton1_4->setText( tr( "2" ) );
pushButton1_2->setText( tr( "4" ) );
pushButton1_2_2->setText( tr( "8" ) );
pushButton9->setText( tr( "next" ) );
}
void Form1::next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::press_next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Right)
press_next();
else
QWidget::keyPressEvent (e);
}
void Form1:: mouseMoveEvent ( QMouseEvent * e )
{
if(e->x() < 260 && e->x() > 210 && e->y() > 80 && e->y() < 120)
pushButton1_3_2-> resize(61,51);
else if(e->x() < 120 && e->x() > 70 && e->y() > 20 && e->y() < 60)
pushButton1->resize(61,51);
else if(e->x() < 260 && e->x() > 210 && e->y() > 20 && e->y() < 60)
pushButton1_3->resize(61,51);
else
{
pushButton1_3_2->resize(51,41);
pushButton1->resize(51,41);
pushButton1_3->resize(51,41);
QWidget::mouseMoveEvent(e);
}
}
[cpp] view
plaincopy
#include "form1.h"
#include "form2.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form1 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form1::Form1( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form1" );
setMouseTracking (true);
pushButton1_3_2 = new QPushButton( this, "pushButton1_3_2" );
pushButton1_3_2->setGeometry( QRect( 210, 80, 51, 41 ) );
pushButton1_3_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_4_2 = new QPushButton( this, "pushButton1_4_2" );
pushButton1_4_2->setGeometry( QRect( 140, 80, 51, 41 ) );
pushButton1_4_2->setFocusPolicy(QWidget::NoFocus);
pushButton1 = new QPushButton( this, "pushButton1" );
pushButton1->setGeometry( QRect( 70, 20, 51, 41 ) );
pushButton1->setFocusPolicy(QWidget::NoFocus);
pushButton1_3 = new QPushButton( this, "pushButton1_3" );
pushButton1_3->setGeometry( QRect( 210, 20, 51, 41 ) );
pushButton1_3->setFocusPolicy(QWidget::NoFocus);
pushButton1_5 = new QPushButton( this, "pushButton1_5" );
pushButton1_5->setGeometry( QRect( 70, 80, 51, 41 ) );
pushButton1_5->setFocusPolicy(QWidget::NoFocus);
pushButton1_4 = new QPushButton( this, "pushButton1_4" );
pushButton1_4->setGeometry( QRect( 140, 20, 51, 41 ) );
pushButton1_4->setFocusPolicy(QWidget::NoFocus);
pushButton1_2 = new QPushButton( this, "pushButton1_2" );
pushButton1_2->setGeometry( QRect( 280, 20, 51, 41 ) );
pushButton1_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_2_2 = new QPushButton( this, "pushButton1_2_2" );
pushButton1_2_2->setGeometry( QRect( 280, 80, 51, 41 ) );
pushButton1_2_2->setFocusPolicy(QWidget::NoFocus);
pushButton9 = new QPushButton( this, "pushButton9" );
pushButton9->setGeometry( QRect( 340, 160, 70, 30 ) );
pushButton9->setFocusPolicy(QWidget::NoFocus);
languageChange();
resize( QSize(434, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton9, SIGNAL( clicked() ), this, SLOT( next() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form1::~Form1()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form1::languageChange()
{
setCaption( tr( "Form1" ) );
pushButton1_3_2->setText( tr( "7" ) );
pushButton1_4_2->setText( tr( "6" ) );
pushButton1->setText( tr( "1" ) );
pushButton1_3->setText( tr( "3" ) );
pushButton1_5->setText( tr( "5" ) );
pushButton1_4->setText( tr( "2" ) );
pushButton1_2->setText( tr( "4" ) );
pushButton1_2_2->setText( tr( "8" ) );
pushButton9->setText( tr( "next" ) );
}
void Form1::next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::press_next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Right)
press_next();
else
QWidget::keyPressEvent (e);
}
void Form1:: mouseMoveEvent ( QMouseEvent * e )
{
if(e->x() < 260 && e->x() > 210 && e->y() > 80 && e->y() < 120)
pushButton1_3_2-> resize(61,51);
else if(e->x() < 120 && e->x() > 70 && e->y() > 20 && e->y() < 60)
pushButton1->resize(61,51);
else if(e->x() < 260 && e->x() > 210 && e->y() > 20 && e->y() < 60)
pushButton1_3->resize(61,51);
else
{
pushButton1_3_2->resize(51,41);
pushButton1->resize(51,41);
pushButton1_3->resize(51,41);
QWidget::mouseMoveEvent(e);
}
}
[cpp] view
plain copy
#include "form1.h"
#include "form2.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form1 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form1::Form1( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form1" );
setMouseTracking (true);
pushButton1_3_2 = new QPushButton( this, "pushButton1_3_2" );
pushButton1_3_2->setGeometry( QRect( 210, 80, 51, 41 ) );
pushButton1_3_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_4_2 = new QPushButton( this, "pushButton1_4_2" );
pushButton1_4_2->setGeometry( QRect( 140, 80, 51, 41 ) );
pushButton1_4_2->setFocusPolicy(QWidget::NoFocus);
pushButton1 = new QPushButton( this, "pushButton1" );
pushButton1->setGeometry( QRect( 70, 20, 51, 41 ) );
pushButton1->setFocusPolicy(QWidget::NoFocus);
pushButton1_3 = new QPushButton( this, "pushButton1_3" );
pushButton1_3->setGeometry( QRect( 210, 20, 51, 41 ) );
pushButton1_3->setFocusPolicy(QWidget::NoFocus);
pushButton1_5 = new QPushButton( this, "pushButton1_5" );
pushButton1_5->setGeometry( QRect( 70, 80, 51, 41 ) );
pushButton1_5->setFocusPolicy(QWidget::NoFocus);
pushButton1_4 = new QPushButton( this, "pushButton1_4" );
pushButton1_4->setGeometry( QRect( 140, 20, 51, 41 ) );
pushButton1_4->setFocusPolicy(QWidget::NoFocus);
pushButton1_2 = new QPushButton( this, "pushButton1_2" );
pushButton1_2->setGeometry( QRect( 280, 20, 51, 41 ) );
pushButton1_2->setFocusPolicy(QWidget::NoFocus);
pushButton1_2_2 = new QPushButton( this, "pushButton1_2_2" );
pushButton1_2_2->setGeometry( QRect( 280, 80, 51, 41 ) );
pushButton1_2_2->setFocusPolicy(QWidget::NoFocus);
pushButton9 = new QPushButton( this, "pushButton9" );
pushButton9->setGeometry( QRect( 340, 160, 70, 30 ) );
pushButton9->setFocusPolicy(QWidget::NoFocus);
languageChange();
resize( QSize(434, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton9, SIGNAL( clicked() ), this, SLOT( next() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form1::~Form1()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form1::languageChange()
{
setCaption( tr( "Form1" ) );
pushButton1_3_2->setText( tr( "7" ) );
pushButton1_4_2->setText( tr( "6" ) );
pushButton1->setText( tr( "1" ) );
pushButton1_3->setText( tr( "3" ) );
pushButton1_5->setText( tr( "5" ) );
pushButton1_4->setText( tr( "2" ) );
pushButton1_2->setText( tr( "4" ) );
pushButton1_2_2->setText( tr( "8" ) );
pushButton9->setText( tr( "next" ) );
}
void Form1::next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::press_next()
{
Form2 a;
a.show();
close();
a.exec();
}
void Form1::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Right)
press_next();
else
QWidget::keyPressEvent (e);
}
void Form1:: mouseMoveEvent ( QMouseEvent * e )
{
if(e->x() < 260 && e->x() > 210 && e->y() > 80 && e->y() < 120)
pushButton1_3_2-> resize(61,51);
else if(e->x() < 120 && e->x() > 70 && e->y() > 20 && e->y() < 60)
pushButton1->resize(61,51);
else if(e->x() < 260 && e->x() > 210 && e->y() > 20 && e->y() < 60)
pushButton1_3->resize(61,51);
else
{
pushButton1_3_2->resize(51,41);
pushButton1->resize(51,41);
pushButton1_3->resize(51,41);
QWidget::mouseMoveEvent(e);
}
}
form2.cpp
[cpp] view
plaincopy
#include "form2.h"
#include "form1.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlabel.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form2 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form2::Form2( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form2" );
pushButton19 = new QPushButton( this, "pushButton19" );
pushButton19->setGeometry( QRect( 20, 160, 71, 31 ) );
textLabel1 = new QLabel( this, "textLabel1" );
textLabel1->setGeometry( QRect( 130, 40, 171, 81 ) );
languageChange();
resize( QSize(435, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton19, SIGNAL( clicked() ), this, SLOT( back() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form2::~Form2()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form2::languageChange()
{
setCaption( tr( "Form2" ) );
pushButton19->setText( tr( "back" ) );
pushButton19->setFocusPolicy(QWidget::NoFocus);
textLabel1->setText( tr( "<h1>hello world</h1>" ) );
}
void Form2::back()
{
Form1 a;
a.show();
close();
a.exec();
}
;
void Form2::press_back()
{
Form1 a;
a.show();
close();
a.exec();
}
void Form2::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Left)
press_back();
else
QWidget::keyPressEvent (e);
}
[cpp] view
plaincopy
#include "form2.h"
#include "form1.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlabel.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form2 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form2::Form2( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form2" );
pushButton19 = new QPushButton( this, "pushButton19" );
pushButton19->setGeometry( QRect( 20, 160, 71, 31 ) );
textLabel1 = new QLabel( this, "textLabel1" );
textLabel1->setGeometry( QRect( 130, 40, 171, 81 ) );
languageChange();
resize( QSize(435, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton19, SIGNAL( clicked() ), this, SLOT( back() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form2::~Form2()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form2::languageChange()
{
setCaption( tr( "Form2" ) );
pushButton19->setText( tr( "back" ) );
pushButton19->setFocusPolicy(QWidget::NoFocus);
textLabel1->setText( tr( "<h1>hello world</h1>" ) );
}
void Form2::back()
{
Form1 a;
a.show();
close();
a.exec();
}
;
void Form2::press_back()
{
Form1 a;
a.show();
close();
a.exec();
}
void Form2::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Left)
press_back();
else
QWidget::keyPressEvent (e);
}
[cpp] view
plain copy
#include "form2.h"
#include "form1.h"
#include <qvariant.h>
#include <qpushbutton.h>
#include <qlabel.h>
#include <qlayout.h>
#include <qtooltip.h>
#include <qwhatsthis.h>
#include <qimage.h>
#include <qpixmap.h>
/*
* Constructs a Form2 as a child of 'parent', with the
* name 'name' and widget flags set to 'f'.
*
* The dialog will by default be modeless, unless you set 'modal' to
* TRUE to construct a modal dialog.
*/
Form2::Form2( QWidget* parent, const char* name, bool modal, WFlags fl )
: QDialog( parent, name, modal, fl )
{
if ( !name )
setName( "Form2" );
pushButton19 = new QPushButton( this, "pushButton19" );
pushButton19->setGeometry( QRect( 20, 160, 71, 31 ) );
textLabel1 = new QLabel( this, "textLabel1" );
textLabel1->setGeometry( QRect( 130, 40, 171, 81 ) );
languageChange();
resize( QSize(435, 204).expandedTo(minimumSizeHint()) );
clearWState( WState_Polished );
// signals and slots connections
connect( pushButton19, SIGNAL( clicked() ), this, SLOT( back() ) );
}
/*
* Destroys the object and frees any allocated resources
*/
Form2::~Form2()
{
// no need to delete child widgets, Qt does it all for us
}
/*
* Sets the strings of the subwidgets using the current
* language.
*/
void Form2::languageChange()
{
setCaption( tr( "Form2" ) );
pushButton19->setText( tr( "back" ) );
pushButton19->setFocusPolicy(QWidget::NoFocus);
textLabel1->setText( tr( "<h1>hello world</h1>" ) );
}
void Form2::back()
{
Form1 a;
a.show();
close();
a.exec();
}
;
void Form2::press_back()
{
Form1 a;
a.show();
close();
a.exec();
}
void Form2::keyPressEvent ( QKeyEvent * e )
{
if(e->key()==Key_Left)
press_back();
else
QWidget::keyPressEvent (e);
}
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