1,QPainter 绘制,先绘制这一堆蓝色的东西,
2,在用定时器:QTimer,配合绘制棕色的圆。用到取余,取整
#pragma once
#include <QWidget>
#include <QPaintEvent>
#include <QTimer>
QT_BEGIN_NAMESPACE
namespace Ui { class RadarSearchBeam; };
QT_END_NAMESPACE
class RadarSearchBeam : public QWidget
{
Q_OBJECT
public:
RadarSearchBeam(QWidget *parent = nullptr);
~RadarSearchBeam();
//绘图事件
void paintEvent(QPaintEvent* event);
//画横着一排圆圈
void drawARow(QPainter &painter, QPointF center,int width, int height);
//画竖着的几排
void drawAColumn(QPainter& painter, QPointF center, int width, int height);
.//把上面两个方法封装了
void drawSearchBeam(QPainter& painter, QPointF center, int width,int height);
//画棕色的圆圈
void drawAbearColorCircle(QPainter& painter, QPointF center, int width, int height);
private:
Ui::RadarSearchBeam *ui;
int R = 10;
int diameter = 2 * R;
QTimer* timer; //定时器
int timer_count;//定时器计数
};
cpp文件
#include "RadarSearchBeam.h"
#include "ui_RadarSearchBeam.h"
#include<QPainter>
#include<QDebug>
RadarSearchBeam::RadarSearchBeam(QWidget *parent)
: QWidget(parent)
, ui(new Ui::RadarSearchBeam())
{
ui->setupUi(this);
//使用定时器
timer_count = 0;
timer = new QTimer(this);
connect(timer, &QTimer::timeout, [=] {
timer_count++;
qDebug() << timer_count << "dfddd";
});
timer->start(100);
}
RadarSearchBeam::~RadarSearchBeam()
{
delete ui;
}
void RadarSearchBeam::paintEvent(QPaintEvent* event)
{
Q_UNUSED(event);
QPainter painter(this);
// 设置画笔颜色
painter.setPen(QColor(0, 160, 230));
//把坐标原点移动到正中间
painter.translate(width()/2,height()/2);
drawSearchBeam(painter, QPointF(0,0),200,200);
drawAbearColorCircle(painter, QPointF(0, 0), 200, 200);
}
void RadarSearchBeam::drawSearchBeam(QPainter& painter, QPointF center, int width, int height)
{
//把坐标原点(正中间)移动到矩形左上角
painter.translate(center.x() - width / 2, center.y() - height / 2);
//把所有蓝色圆圈画完
drawARow(painter, QPointF(0,0),width, height);
drawAColumn(painter, QPointF(0, 0), width, height);
}
//配合定时器画移动的棕色圆圈
void RadarSearchBeam::drawAbearColorCircle(QPainter& painter, QPointF center, int width, int height)
{
//一排几个圆=宽/直径
int row_circle_num = width / diameter;
//一竖几个圆=高/直径
int column_circle_num = height / diameter;
//总共多少个圆
int all_circle_um = row_circle_num * column_circle_num;
//这两个是配合定时器用
int move_distance_x = diameter;
int move_distance_y = diameter;
//计时数小于圆圈数
if (timer_count < all_circle_um)
{
int current_column_num = timer_count % row_circle_num;;
int current_row_num = timer_count / row_circle_num;
画棕色的圆圈
painter.setPen(QColor(185, 122, 87));
painter.drawEllipse(QPoint(center.x() + move_distance_x*current_column_num, center.y()+ current_row_num* move_distance_y), R, R);
//刷新绘图事件
update();
}
else
{
// //计时数大于圆圈数,把计时数清零,从新计数
timer_count = 0;
update();
}
}
//画一排
void RadarSearchBeam::drawARow(QPainter& painter, QPointF center,int width, int height)
{
//一排
int row_num = width /diameter;
for (int i = 0; i < row_num; i++)
{
painter.drawEllipse(QPoint(center.x()+i*diameter, center.y()), R, R);
}
}
//竖着画几排
void RadarSearchBeam::drawAColumn(QPainter& painter,QPointF center, int width, int height)
{
int num = height / diameter;
for (int i = 0; i < num; i++)
{
drawARow(painter, QPointF(center.x(), center.y()+ i* diameter), width, height);
qDebug() << QPointF(center.x(), center.y() + i * diameter);
}
}