36.QT地图

  • widget.h 
     1 #ifndef MAPWIDGET_H
 2 #define MAPWIDGET_H
 3 
 4 #include <QGraphicsView>
 5 #include <QLabel>
 6 #include <QMouseEvent>
 7 
 8 class MapWidget : public QGraphicsView
 9 {
10     Q_OBJECT
11 public:
12     MapWidget();
13 
14     void readMap();                         //读取地图信息
15     QPointF mapToMap(QPointF);              //用于实现场景坐标系与地图坐标之间的映射，以获得某点的经纬度值
16 
17 public slots:
18     void slotZoom(int);
19 
20 protected:
21     void drawBackground(QPainter *painter, const QRectF &rect);         //完成地图显示的功能
22     void mouseMoveEvent(QMouseEvent *event);                            //鼠标移动功能
23 
24 private:
25     QPixmap map;        //地图
26     qreal zoom;         //大小
27     QLabel *viewCoord;  //标签
28     QLabel *sceneCoord;
29     QLabel *mapCoord;
30     double x1,y1;
31     double x2,y2;
32 };
33 
34 #endif // MAPWIDGET_H

     

  • widget.cpp 
      1 #include "widget.h"
  2 #include <QSlider>
  3 #include <QGridLayout>
  4 #include <QFile>
  5 #include <QTextStream>
  6 #include <QGraphicsScene>
  7 #include <math.h>
  8 
  9 MapWidget::MapWidget()
 10 {
 11     readMap();                                    //读取地图信息
 12 
 13     zoom=50;
 14 
 15     int width = map.width();
 16     int height = map.height();
 17     QGraphicsScene *scene = new QGraphicsScene(this);
 18     scene->setSceneRect(-width/2,-height/2,width,height);
 19     setScene(scene);
 20     setCacheMode(CacheBackground);
 21 
 22     //用于地图缩放的滑动条
 23     QSlider *slider = new QSlider;
 24     slider->setOrientation(Qt::Vertical);
 25     slider->setRange(1,100);
 26     slider->setTickInterval(10);
 27     slider->setValue(50);
 28     connect(slider,SIGNAL(valueChanged(int)),this,SLOT(slotZoom(int)));
 29 
 30     QLabel *zoominLabel = new QLabel;
 31     zoominLabel->setScaledContents(true);
 32     zoominLabel->setPixmap(QPixmap("zoomin.png"));
 33 
 34     QLabel *zoomoutLabel = new QLabel;
 35     zoomoutLabel->setScaledContents(true);
 36     zoomoutLabel->setPixmap(QPixmap("zoomout.png"));
 37 
 38     //坐标值显示区
 39     QLabel *label1 = new QLabel(tr("GraphicsView:"));
 40     viewCoord = new QLabel;
 41     QLabel *label2 = new QLabel(tr("GraphicsScene:"));
 42     sceneCoord = new QLabel;
 43     QLabel *label3 = new QLabel(tr("map:"));
 44     mapCoord = new QLabel;
 45 
 46     //坐标显示区布局
 47     QGridLayout *gridLayout = new QGridLayout;
 48     gridLayout->addWidget(label1,0,0);
 49     gridLayout->addWidget(viewCoord,0,1);
 50     gridLayout->addWidget(label2,1,0);
 51     gridLayout->addWidget(sceneCoord,1,1);
 52     gridLayout->addWidget(label3,2,0);
 53     gridLayout->addWidget(mapCoord,2,1);
 54     gridLayout->setSizeConstraint(QLayout::SetFixedSize);
 55 
 56     QFrame *coordFrame = new QFrame;
 57     coordFrame->setLayout(gridLayout);
 58 
 59     //缩放控制子布局
 60     QVBoxLayout *zoomLayout = new QVBoxLayout;
 61     zoomLayout->addWidget(zoominLabel);
 62     zoomLayout->addWidget(slider);
 63     zoomLayout->addWidget(zoomoutLabel);
 64 
 65     //坐标显示区域布局
 66     QVBoxLayout *coordLayout = new QVBoxLayout;
 67     coordLayout->addWidget(coordFrame);
 68     coordLayout->addStretch();
 69 
 70     //主布局
 71     QHBoxLayout *mainLayout = new QHBoxLayout;
 72     //滑动
 73     mainLayout->addLayout(zoomLayout);
 74     //坐标
 75     mainLayout->addLayout(coordLayout);
 76     mainLayout->addStretch();
 77     mainLayout->setMargin(30);
 78     mainLayout->setSpacing(10);
 79     setLayout(mainLayout);
 80 
 81     setWindowTitle("Map Widget");
 82     setMinimumSize(600,400);
 83 }
 84 
 85 void MapWidget::readMap()            //读取地图信息
 86 {
 87     QString mapName;
 88     QFile mapFile("maps.txt");
 89     //打开文件
 90     int ok = mapFile.open(QIODevice::ReadOnly);
 91     if(ok)
 92     {
 93         QTextStream ts(&mapFile);
 94         if(!ts.atEnd())
 95         {
 96             ts>>mapName;
 97             ts>>x1>>y1>>x2>>y2;
 98         }
 99     }
100     //载入地图
101     map.load(mapName);
102 }
103 
104 void MapWidget::slotZoom(int value)       //地图缩放与放大
105 {
106     qreal s;
107     if(value>zoom)                         //放大
108     {
109         s=pow(1.01,(value-zoom));
110     }
111     else                                 //缩小
112     {
113         s=pow(1/1.01,(zoom-value));
114     }
115     scale(s,s);//放大缩小
116    // rotate(s);
117     zoom = value;
118 }
119 
120 //绘制背景
121 void MapWidget::drawBackground(QPainter *painter, const QRectF &rect)
122 {
123     painter->drawPixmap(int(sceneRect().left()),int(sceneRect().top()), map);//绘图
124 }
125 
126 void MapWidget::mouseMoveEvent(QMouseEvent *event)
127 {
128     //QGraphicsView 坐标
129     QPoint viewPoint = event->pos();
130     viewCoord->setText(QString::number(viewPoint.x())+","+QString::number(viewPoint.y()));
131 
132     //QGraphicsScene 坐标
133     QPointF scenePoint = mapToScene(viewPoint);
134     sceneCoord->setText(QString::number(scenePoint.x())+","+QString::number(scenePoint.y()));
135 
136     //地图坐标(经、纬度值)
137     QPointF latLon = mapToMap(scenePoint);
138     mapCoord->setText(QString::number(latLon.x())+","+QString::number(latLon.y()));
139 }
140 
141 //用于实现场景坐标系与地图坐标之间的映射，以获得某点的经纬度值
142 QPointF MapWidget::mapToMap(QPointF p)
143 {
144     QPointF latLon;
145     qreal w =sceneRect().width();
146     qreal h =sceneRect().height();
147 
148     qreal lon = y1-((h/2+p.y())*abs(y1-y2)/h);
149     qreal lat = x1+((w/2+p.x())*abs(x1-x2)/w);
150 
151     latLon.setX(lat);
152     latLon.setY(lon);
153 
154     return latLon;
155 }

     

  • main.c 
     1 #include "widget.h"
 2 #include <QApplication>
 3 
 4 int main(int argc, char *argv[])
 5 {
 6     QApplication a(argc, argv);
 7     //设置字体
 8     QFont font("ARPL KaitiM GB",12);
 9     font.setBold(true);
10     a.setFont(font);
11 
12     //显示
13     MapWidget w;
14     w.show();
15 
16     return a.exec();
17 }

     

posted @ 2018-04-11 16:53  喵小喵~  阅读(1199)  评论(0)    收藏  举报