QT实现自定义控件

最近在看自定义控件，感觉非常炫酷好看，然后自己尝试了一下，欢迎交流讨论，效果如下所示：

当你按下按钮可以改变仪表盘的速度，也可以改变小鸡孵化的速度：
参考链接：
qt程序实现多个图片连续显示效果像动画一样_qgraphicsscene多幅图片依次显示-CSDN博客
Qt实现仪表盘-自定义控件-CSDN博客
需要注意的是weight的提升，以及painter的使用。
下面是核心代码：

#include "dashboardwidget.h"#include <QPainter>
#include <QPropertyAnimation>
#include <QtMath>struct DashBoardWidgetPrivate{int maxValue = 100;int minValue = 0;double startAngle = -50;double endAngle = 230;int value = minValue;int scaleMajor = 10;int scaleMinor = 5;QString unit = "unit";QString text = "test";QColor arcColor = QColor(56, 61, 74);QColor scaleColor = QColor(4, 168, 173);QColor pointerColor = QColor(4, 181, 200);QColor textColor = QColor(144, 133, 116);QColor backgroundColor = Qt::transparent;QPropertyAnimation *animation;
};DashBoardWidget::DashBoardWidget(QWidget *parent): QWidget(parent), d(new DashBoardWidgetPrivate)
{d->animation = new QPropertyAnimation(this, "value", this);setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);connect(this, &DashBoardWidget::valueChanged, this, &DashBoardWidget::onStartAnimation);
}DashBoardWidget::~DashBoardWidget()
{
}QSize DashBoardWidget::sizeHint() const
{return QSize(300, 300);
}QSize DashBoardWidget::minimumSizeHint() const
{return QSize(200, 200);
}void DashBoardWidget::setMin(const double min)
{d->minValue = min;update();
}double DashBoardWidget::min() const
{return d->minValue;
}void DashBoardWidget::setmax(const double max)
{d->maxValue = max;update();
}double DashBoardWidget::max() const
{return d->maxValue;
}void DashBoardWidget::setStartAngle(const double startAngle)
{d->startAngle = startAngle;update();
}double DashBoardWidget::startAngle() const
{return d->startAngle;
}void DashBoardWidget::setEndAngle(const double endAngle)
{d->endAngle = endAngle;update();
}double DashBoardWidget::endAngle() const
{return d->endAngle;
}void DashBoardWidget::setScaleMajor(const int scale)
{d->scaleMajor = scale;update();
}int DashBoardWidget::scaleMajor() const
{return d->scaleMajor;
}void DashBoardWidget::setScaleMinor(const int scale)
{d->scaleMinor = scale;update();
}int DashBoardWidget::scaleMinor() const
{return d->scaleMinor;
}void DashBoardWidget::setUnit(const QString &unit)
{d->unit = unit;update();
}QString DashBoardWidget::unit() const
{return d->unit;
}void DashBoardWidget::setText(const QString &text)
{d->text = text;update();
}QString DashBoardWidget::text() const
{return d->text;
}void DashBoardWidget::setArcColor(const QColor &color)
{d->arcColor = color;update();
}QColor DashBoardWidget::arcColor() const
{return d->arcColor;
}void DashBoardWidget::setScaleColor(const QColor &color)
{d->scaleColor = color;update();
}QColor DashBoardWidget::scaleColor() const
{return d->scaleColor;
}void DashBoardWidget::setPointerColor(const QColor &color)
{d->pointerColor = color;update();
}QColor DashBoardWidget::pointerColor() const
{return d->pointerColor;
}void DashBoardWidget::setTextColor(const QColor &color)
{d->textColor = color;update();
}QColor DashBoardWidget::textColor() const
{return d->textColor;
}void DashBoardWidget::setBackgroundColor(const QColor &color)
{d->backgroundColor = color;update();
}QColor DashBoardWidget::backgroundColor() const
{return d->backgroundColor;
}void DashBoardWidget::paintEvent(QPaintEvent *event)
{QWidget::paintEvent(event);QPainter painter(this);painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);// 背景// if (d->backgroundColor != Qt::transparent) {//     painter.setPen(Qt::NoPen);//     painter.fillRect(rect(), d->backgroundColor);// }// 平移中心painter.translate(width() / 2, height() / 2);// 圆环drawArc(&painter);// 刻度线drawScale(&painter);// 刻度值drawScaleNum(&painter);// 指示器drawPointer(&painter);// 当前值drawValue(&painter);
}void DashBoardWidget::onStartAnimation(const double value)
{if(value < d->minValue|| value > d->maxValue|| value == d->value)return;int start = d->value;int end = value;d->animation->setStartValue(start);d->animation->setEndValue(end);d->animation->start();
}double DashBoardWidget::value() const
{return d->value;
}void DashBoardWidget::setValue(const double value)
{d->value = value;update();
}//画圆弧
void DashBoardWidget::drawArc(QPainter *painter)
{double min = qMin(width(), height());double arcWidth = min / 15.0;double radius = min / 3 - arcWidth;QRectF rect = QRectF(-radius, -radius, radius * 2, radius * 2);// 创建一个线性渐变QLinearGradient gradient(rect.topLeft(), rect.bottomRight());gradient.setColorAt(0.0, QColor(255, 0, 0)); // 起始颜色：红色gradient.setColorAt(1.0, QColor(0, 0, 255)); // 终止颜色：蓝色QPen pen;pen.setWidthF(arcWidth);pen.setCapStyle(Qt::FlatCap);// 设置画笔为渐变色QBrush brush(gradient);pen.setBrush(brush);// 圆弧背景double angle = d->endAngle - d->startAngle;painter->setPen(pen);painter->drawArc(rect, d->startAngle * 16, angle * 16);
}void DashBoardWidget::drawScale(QPainter *painter)
{painter->save();painter->rotate(270 - d->endAngle);int steps = (d->scaleMajor * d->scaleMinor);double angleStep = (d->endAngle - d->startAngle) / steps;double min = qMin(width(), height());double radius = min / 3;QPen pen(d->scaleColor);pen.setCapStyle(Qt::RoundCap);for (int i = 0; i <= steps; i++) {if (i % d->scaleMinor == 0) {pen.setWidthF(1.5);painter->setPen(pen);painter->drawLine(0, radius - 8, 0, radius + 5);} else {pen.setWidthF(0.5);painter->setPen(pen);painter->drawLine(0, radius - 8, 0, radius - 3);}painter->rotate(angleStep);}painter->restore();
}void DashBoardWidget::drawScaleNum(QPainter *painter)
{painter->save();painter->setPen(d->scaleColor);double min = qMin(width(), height());double radius = min / 2.4;QFont font("Microsoft YaHei", min / 25);painter->setFont(font);double startRad = d->endAngle * (M_PI / 180);double deltaRad = (d->endAngle - d->startAngle) * (M_PI / 180) / d->scaleMajor;QFontMetrics fontMetrics(font);for (int i = 0; i <= d->scaleMajor; i++) {double sina = qSin(startRad - i * deltaRad);double cosa = qCos(startRad - i * deltaRad);double value = 1.0 * i * ((d->maxValue - d->minValue) / d->scaleMajor) + d->minValue;QString strValue = QString("%1").arg(value);double textWidth = fontMetrics.horizontalAdvance(strValue);double textHeight = fontMetrics.height();int x = radius * cosa - textWidth / 2;int y = -radius * sina + textHeight / 4;painter->drawText(x, y, strValue);}painter->restore();
}void DashBoardWidget::drawPointer(QPainter *painter)
{painter->save();painter->setPen(Qt::NoPen);painter->setBrush(d->pointerColor);double radius = qMin(width(), height()) / 3.0;QPolygonF pts;pts << QPointF(-5, 0) << QPointF(0, -8)<< QPointF(5, 0) << QPointF(0, radius);painter->rotate(270 - d->endAngle);double degRotate = (d->endAngle - d->startAngle) / (d->maxValue - d->minValue) * (d->value - d->minValue);painter->rotate(degRotate);painter->drawConvexPolygon(pts);painter->restore();
}void DashBoardWidget::drawValue(QPainter *painter)
{painter->save();painter->setPen(d->textColor);double min = qMin(width(), height());double radius = min / 2.0 - min / 4.8;QFont font("Microsoft YaHei", min / 25);painter->setFont(font);QString strValue = QString("%1").arg(d->value);strValue = QString("%1 %2").arg(strValue, d->unit);QRectF valueRect(-radius, radius / 2.5, radius * 2, radius / 3.5);painter->drawText(valueRect, Qt::AlignCenter, strValue);QRectF textRect(-radius, radius / 1.5, radius * 2, radius / 2.5);//font.setPixelSize(12);painter->setFont(font);painter->drawText(textRect, Qt::AlignCenter, d->text);painter->restore();
}void DashBoardWidget::setSpeed(int speed)
{if (speed < minValue)speed = minValue;else if (speed > maxValue)speed = maxValue;d->value = speed;update();
}

所有代码：https://gitee.com/wangning719/dash-board-widget