Qt浅谈之三十九圆形进度条

本文主要是介绍Qt浅谈之三十九圆形进度条，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

一、简介

Qt下进度条一般都是水平或垂直的，有时需要一个椭圆或圆来动态显示进度，或用此来显示存储百分比，都是比较适用的。

二、详解

1、代码

（1）widgetdisplay.h

#ifndef WIDGET_H
#define WIDGET_H#include <QtCore>
#include <QtGui>class StorageDisplay : public QWidget
{Q_OBJECT
public:StorageDisplay(QWidget *parent = 0);~StorageDisplay();void setUsedValue(int value);//void setSize(int width, int height);
protected:void paintEvent(QPaintEvent *event);void resizeEvent (QResizeEvent * event);void mousePressEvent(QMouseEvent *event);void mouseMoveEvent(QMouseEvent *event);void mouseReleaseEvent(QMouseEvent *event);void showEvent(QShowEvent *event);void hideEvent(QHideEvent *event);private slots:void slotUpdateTimer();private:QPoint beginDrag;bool bPressFlag;QPixmap backGround;int userdVaule;int currentValue;QLabel *startValueLabel;QLabel *endValueLabel;QLabel *dispayValueLabel;QTimer *updateTimer;
};#endif // WIDGET_H

（2）widgetdisplay.cpp

#include "widgetdisplay.h"StorageDisplay::StorageDisplay(QWidget *parent): QWidget(parent, Qt::FramelessWindowHint), bPressFlag(false), currentValue(0)
{QTextCodec *codec = QTextCodec::codecForName("utf8");QTextCodec::setCodecForLocale(codec);QTextCodec::setCodecForCStrings(codec);QTextCodec::setCodecForTr(codec);resize(167, 167);setAutoFillBackground(false);QPalette pal = palette();pal.setColor(QPalette::Background, QColor(0xFF,0xFF,0xFF,0xFF));setPalette(pal);startValueLabel = new QLabel(tr("0%"), this);startValueLabel->setFont(QFont("Arial", 11, QFont::Normal));startValueLabel->setStyleSheet("color:#898989");endValueLabel = new QLabel(tr("100%"),this);endValueLabel->setFont(QFont("Arial", 11, QFont::Normal));endValueLabel->setStyleSheet("color:#898989");dispayValueLabel = new QLabel(this);dispayValueLabel->setStyleSheet("color:#349BDA");updateTimer = new QTimer(this);updateTimer->setInterval(20);connect(updateTimer, SIGNAL(timeout()), this, SLOT(slotUpdateTimer()));
}StorageDisplay::~StorageDisplay()
{if (updateTimer->isActive()) {updateTimer->stop();}currentValue = 0;
}void StorageDisplay::setUsedValue(int value)
{userdVaule = value;
}void StorageDisplay::showEvent(QShowEvent *event)
{updateTimer->start();currentValue = 0;
}void StorageDisplay::hideEvent(QHideEvent *event)
{if (updateTimer->isActive()) {updateTimer->stop();}currentValue = 0;
}void StorageDisplay::slotUpdateTimer()
{if (currentValue >= userdVaule) {updateTimer->stop();return;}currentValue++;update();
}void StorageDisplay::paintEvent(QPaintEvent *event)
{QPainter painter(this);QColor usedColor(165, 220, 62);QColor freeColor(215, 215, 215);painter.drawPixmap(QRect((width() - backGround.width())/2 , (height() - backGround.height())/2, backGround.width(), backGround.height()) , backGround);painter.translate(width() / 2, height() / 2);painter.setRenderHint(QPainter::Antialiasing);painter.setRenderHint(QPainter::SmoothPixmapTransform);painter.save();painter.rotate(42);painter.setPen(QPen(usedColor, 2));for (int i = 0; i < currentValue ; ++i) {painter.drawLine(0, 70, 0, 80);painter.rotate(2.8);}painter.setPen(QPen(freeColor, 3));for (int i = currentValue; i < 100 ; ++i) {painter.drawLine(0, 70, 0, 80);painter.rotate(2.8);}if (currentValue == 0) {dispayValueLabel->setFont(QFont("Arial", 12, QFont::Bold));dispayValueLabel->setText(tr("unconfig"));}else {dispayValueLabel->setFont(QFont("Arial", 15, QFont::Bold));dispayValueLabel->setText(tr("%1%").arg(currentValue));}QFontMetrics metrics(dispayValueLabel->font());int textwidth = metrics.width(dispayValueLabel->text());int textheight = metrics.height();dispayValueLabel->setGeometry((width() - textwidth)/2, (height() - textheight)/2 , textwidth, textheight);painter.restore();painter.translate(-width()/2, -height()/2);painter.setBrush(QColor(233, 233, 233));painter.setPen(QPen(QColor(233, 233, 233), 15));painter.drawEllipse(QRectF((width()/2 - 55), (height()/2 - 55), 110, 110));QConicalGradient conicalGradient(width()/2, height()/2, 90);conicalGradient.setColorAt(0, QColor(45, 204, 112));conicalGradient.setColorAt(1.0, QColor(51, 152, 219));painter.setPen(QPen(QBrush(conicalGradient), 30));painter.drawEllipse(QRectF((width()/2 - 35), (height()/2 - 35), 70, 70));painter.setPen(Qt::NoPen);painter.setBrush(QColor(249, 249, 249));painter.drawEllipse(QRectF((width()/2 - 30), (height()/2 - 30), 60, 60));
}void StorageDisplay::resizeEvent(QResizeEvent *event)
{move((QApplication::desktop()->width() - width())/2,  (QApplication::desktop()->height() - height())/2);startValueLabel->setGeometry(35, 140, 25, 20);endValueLabel->setGeometry(97, 140, 50, 20);
}/****************move everywhere*******************/
void StorageDisplay::mousePressEvent(QMouseEvent *event)
{bPressFlag = true;beginDrag = event->pos();QWidget::mousePressEvent(event);
}void StorageDisplay::mouseMoveEvent(QMouseEvent *event)
{if (bPressFlag) {QPoint relaPos(QCursor::pos() - beginDrag);move(relaPos);}QWidget::mouseMoveEvent(event);
}void StorageDisplay::mouseReleaseEvent(QMouseEvent *event)
{bPressFlag = false;QWidget::mouseReleaseEvent(event);
}

</pre><pre>

（3）main.cpp

#include "widgetdisplay.h"
#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);StorageDisplay w;w.setUsedValue(100);w.show();return a.exec();
}

（4）编译运行