event.cpp

几个qt-linux的练习小程序

#include <qwidget.h>
#include <qpainter.h>
#include <qpicture.h>
#include <qlabel.h>
#include <qstring.h>
#include <qapplication.h>
#include <math.h>
#include <qevent.h>


class MyMainWindow:public QWidget
{
public:
  MyMainWindow(QWidget* parent=0);

void ReSize(int x, int y);

};
void MyMainWindow::ReSize(int X, int Y)
{
    resize(X, Y);
}
MyMainWindow::MyMainWindow(QWidget *parent):QWidget(parent)
{
}


class DrawWidget:public QWidget
{
public:
   DrawWidget();
   MyMainWindow *draw;
protected:
    void drawIt( QPainter * );
    void drawIt1( QPainter *p , QString a );
    void paintEvent( QPaintEvent * );
    void keyPressEvent(QKeyEvent *event);
private:
    void drawFonts(QPainter *p);
  void drawFonts1(QPainter *p, QString a);
};

DrawWidget::DrawWidget() : QWidget()
{
    draw = new MyMainWindow(this);
        qDebug("--------");
    draw->ReSize(750, 550);
    draw->setBackgroundColor(red);
    update();
    resize(800, 600);
}

void DrawWidget::drawIt( QPainter *p )
{
    drawFonts(p);
}

void DrawWidget::drawFonts( QPainter *p )
{
    p->drawText(10,10,"Please press 'shift' or 'end', thinks");
}

//keyevent
void DrawWidget::drawIt1( QPainter *p , QString a)
{
    drawFonts1(p , a);
}
void DrawWidget::drawFonts1( QPainter *p, QString a)
{
    p->drawText(100,100,a);

}

//
void DrawWidget::paintEvent( QPaintEvent *)
{
    QPainter paint( draw );
    drawIt( &paint );
}

void DrawWidget::keyPressEvent(QKeyEvent *event)
{
    draw->erase ();
    QPainter paint( draw );
 /*   int b = event->key();
    QString a = b + "";
    drawIt1( &paint , a);  */
    QString a;
    switch (event->key()){
	case Key_Shift:
    		a ="the key is shift";
		break;
	case Key_End:
		a ="the key is end";
		break;
    }
    drawIt1( &paint , a);
    
}



int main(int argc,char** argv)
{
  QApplication app(argc,argv);
  DrawWidget w;
  
  app.setMainWidget(&w);

  w.show();
  return app.exec();
}