【Qt程式設計】設計ColorBar顏色欄
阿新 • • 發佈:2019-02-02
#include <QApplication> #include <QWidget> #include <QPainter> class PainterWidget : public QWidget { protected: void paintEvent(QPaintEvent*); }; void PainterWidget::paintEvent(QPaintEvent *event) { QPainter painter(this); QColor color; QRect section; float colorBarLength=343.0;//設定顏色條的長度 //------設定為gray顏色條---------// for(int i=0;i<=colorBarLength;i++)// gray { //color.setRgbF(i/colorBarLength,i/colorBarLength,i/colorBarLength);//也可以使用這種方法 color.setHsv(0,0,(colorBarLength-i)/colorBarLength*255); section.setRect(150,50+i*1,20,1); painter.fillRect(section,color); } //------設定為jet顏色條---------// float tempLength=colorBarLength/4; for(int i=0;i<tempLength/2;i++)// jet { color.setRgbF(0,0,(tempLength/2+i)/tempLength); section.setRect(200,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+1;i<tempLength/2+tempLength;i++)// jet { color.setRgbF(0,(i-tempLength/2)/tempLength,1); section.setRect(200,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+tempLength+1;i<tempLength/2+2*tempLength;i++)// jet { color.setRgbF((i-tempLength-tempLength/2)/tempLength,1,(tempLength*2+tempLength/2-i)/tempLength); section.setRect(200,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+2*tempLength+1;i<tempLength/2+3*tempLength;i++)// jet { color.setRgbF(1,(tempLength*3+tempLength/2-i)/tempLength,0); section.setRect(200,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+3*tempLength+1;i<colorBarLength;i++)// jet { color.setRgbF((colorBarLength-i+tempLength/2)/(tempLength),0,0); section.setRect(200,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } //------設定為hsv顏色條---------// for(int i=0;i<=colorBarLength;i++)// hsv { color.setHsvF(i/colorBarLength,1,1); section.setRect(250,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } //------設定為hot顏色條---------// tempLength=colorBarLength/2.5; for(int i=0;i<tempLength/2;i++)// hot { color.setRgbF((tempLength/2+i)/tempLength,0,0); section.setRect(300,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+1;i<tempLength/2+tempLength;i++)// hot { color.setRgbF(1,(i-tempLength/2)/tempLength,0); section.setRect(300,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } for(int i=tempLength/2+tempLength+1;i<colorBarLength;i++)// hot { color.setRgbF(1,1,(i-tempLength/2-tempLength)/(colorBarLength-tempLength/2-tempLength+20)); section.setRect(300,colorBarLength+50-i*1,20,1); painter.fillRect(section,color); } //---------設定邊框--------------// //刻度值的繪製可以自己設計,使用drawText函式即可,刻度的繪製可以使用drawLine函式 painter.setPen(Qt::black); painter.drawRect(150,50,20,colorBarLength); painter.setFont(QFont(QString::fromLocal8Bit("宋體"),10,-1,false)); painter.drawText(150,40,QStringLiteral("Gray")); painter.drawRect(200,50,20,colorBarLength); painter.setFont(QFont(QString::fromLocal8Bit("宋體"),10,-1,false)); painter.drawText(200,40,QStringLiteral("Jet")); painter.drawRect(250,50,20,colorBarLength); painter.setFont(QFont(QString::fromLocal8Bit("宋體"),10,-1,false)); painter.drawText(250,40,QStringLiteral("Hsv")); painter.drawRect(300,50,20,colorBarLength); painter.setFont(QFont(QString::fromLocal8Bit("宋體"),10,-1,false)); painter.drawText(300,40,QStringLiteral("Hot")); // painter.drawText(150,320,QStringLiteral(" 0")); } int main(int argc, char *argv[]) { QApplication app(argc, argv); PainterWidget pWidget; pWidget.setWindowTitle("ColorTest"); pWidget.resize(500, 500); pWidget.show(); return app.exec(); }