QT实现4G信号图标显示

#include "signalwidget.h" #include <QPainter> SignalWidget::SignalWidget(QWidget *parent) : QWidget(parent) { m_signalStrength = SignalStrength::Zero; } SignalWidget::~SignalWidget() { } void SignalWidget::paintEvent(QPaintEvent *event) { Q_UNUSED(event); QPainter p(this); p.setRenderHint(QPainter::Antialiasing); float hUnit = this->height() / 5.0; int h1 = hUnit * 1; int h2 = hUnit * 2; int h3 = hUnit * 3; int h4 = hUnit * 4; //widget 宽度分为七份，四个信号柱及三个空白区域各占一份 float wUnit = this->width() / 7.0; int x1 = 1; int x2 = wUnit * 2+1; int x3 = wUnit * 4; int x4 = wUnit * 6 - 1; QColor havaSignal = QColor(20, 18, 19); QColor noSignal = Qt::lightGray; QColor colorOne, colorTwo, colorThree, colorFour; colorOne = noSignal; colorTwo = noSignal; colorThree = noSignal; colorFour = noSignal; switch(m_signalStrength) { case SignalStrength::Four: colorFour = havaSignal; case SignalStrength::Three: colorThree = havaSignal; case SignalStrength::Two: colorTwo = havaSignal; case SignalStrength::One: colorOne = havaSignal; default: break; }; p.setPen(colorFour); p.setBrush(colorFour); p.drawRect(x4, this->height() - h4, wUnit, h4); p.setPen(colorThree); p.setBrush(colorThree); p.drawRect(x3, this->height() - h3, wUnit, h3); p.setPen(colorTwo); p.setBrush(colorTwo); p.drawRect(x2, this->height() - h2, wUnit, h2); p.setPen(colorOne); p.setBrush(colorOne); p.drawRect(x1, this->height() - h1, wUnit, h1); QFont font; font.setPixelSize(this->height() / 2.0); font.setBold(true); p.setFont(font); QString text = "4G"; p.drawText(0, this->height() - h2-5,text); if(m_signalStrength == SignalStrength::Zero) { QFontMetrics metrics(font); int w = metrics.width(text); int h = metrics.height(); p.drawLine(x1, this->height() - h,w,1); p.drawLine(x1, 1,w,this->height() - h); } } void SignalWidget::setSignalStrength(SignalStrength newSignalStrength) { m_signalStrength = newSignalStrength; this->update(); }