我已经尝试了很长一段时间了。我需要在支持QRect的Qlabel上绘制多个矩形，我尝试存储QRectF但是在下一个事件之后它取代了矩形并且只显示了一个矩形。 我的代码如下： penlayer.h class PictureLayer：public QLabel { Q_OBJECT float adjustX; float adjustY;
int setRed;
int setGreen;
int setBlue;
int startPointX;
int finalPointX;
int startPointY;
int finalPointY;
QString imagePath;
public:
int x;
int y;
QPixmap showPicture;
QImage imageSource;
QPoint originPoint;
QPoint finalPoint;
QRectF rectColorFrame;
explicit PictureLayer(QWidget *parent = 0);
~PictureLayer(){}
void leaveEvent(QEvent *);
void mousePressEvent(QMouseEvent *e);
void mouseReleaseEvent (QMouseEvent *e);
void mouseMoveEvent(QMouseEvent *e);
void imageManipulation(QPoint , QPoint);
// void /*paintEvent*/(QPaintEvent *);
signals:
void mouse_pressed();
void mouse_release();
void mouse_pos();
void mouse_left();
private:
};
和...
#include "penlayer.h"
PictureLayer::PictureLayer(QWidget *parent) :
QLabel (parent)
{
adjustX = 0.0;
adjustY = 0.0;
setRed = 0;
setBlue = 0;
setGreen = 0;
startPointX = 0;
startPointY = 0;
finalPointY = 0;
finalPointX = 0;
x =0;
y =0;
// Source_Path =":/new/prefix1/testpic/just.jpg";
// Source_Path =":/testpic/tst.jpg";
imagePath =":/testpic/sed.JPG";
imageManipulation(QPoint (0,0), QPoint (0,0));
}
PenLayer::PenLayer(QWidget *parent) :
QLabel (parent)
{
x = 0;
y = 0;
rectIntNumber = 0;
storeRectanglePoints (QPoint (0,0) , QPoint (0,0), 0);
}//constructor
/********************Mouse Events********************/
void PenLayer::mouseMoveEvent (QMouseEvent *e)
{
this->x = e->x();
this->y = e->y();
emit mouse_pos(/*Look for an event to hold*/);
}///mouseMoveEvent
void PenLayer::mousePressEvent(QMouseEvent *e)
{
this-> x = e->x ();
this-> y = e->y ();
emit mouse_pressed ();
}///mousePressEvent
void PenLayer::mouseReleaseEvent (QMouseEvent *e)
{
this-> x = e->x ();
this-> y = e->y ();
emit mouse_release();
}///mouseReleaseEvent
void PenLayer::leaveEvent(QEvent *)
{
emit mouse_left();
}///leaveEvent
/*************************Setting rectangle***************************/
void PenLayer::storeRectanglePoints (QPoint p1 , QPoint p2, int num)
{
rectIntNumber = num;
pressPoint = p1;
releasePoint = p2;
pressPair.first = pressPoint.rx ();
pressPair.second = pressPoint.ry ();
listOfPoints.insert (rectIntNumber, pressPair);
releasePair.first = releasePoint.rx ();
releasePair.second = releasePoint.ry ();
listOfPoints.insert (rectIntNumber, releasePair);
// rect_storeRectanglePoints.setRect (pressPair.first, pressPair.second,
// releasePair.first, releasePair.second);
// rect.insert(rectIntNumber, &rect_storeRectanglePoints);
qDebug()<<rect;
}///setRectanglePoints
/*************************PaintEvent rectangle***************************/
void PenLayer::paintEvent(QPaintEvent *pa)
{
QPainter painter(this);
QRectF rectangle( pressPoint , releasePoint );
// QPair to QPoint
if(pressPoint != QPoint(0,0))
{
painter.setPen(QPen(Qt::red, 3.0,
Qt::DotLine,
Qt::SquareCap,
Qt::MiterJoin));
pa->accept ();
}
else
painter.setPen (QPen(Qt::transparent));
// painter.drawRects(&rectangle,rectIntNumber);
//Should draw many rectangles, but wont
// qDebug()<<"painter test: clickAction->"<<clickAction;
painter.drawRect(/**rect.last ()*/rectangle);
//QPainter should be in the qlist
// painter.end ();
// onColorRect.insert (rectIntNumber, &painter);
// qDebug()<<onColorRect;
}///paintEvent
dialogfile
#include "dialog.h"
#include "uidialog.h"
#include "picturelayer.h"
#include "penlayer.h"
Dialog::Dialog(QWidget *parent) :
QDialog(parent),
ui(new Ui::Dialog)
{
ui->setupUi(this);
rectangleNumber = 0;
/*************************CONNECT STATEMENTS***************************/
connect(ui-> selectToolLabel, SIGNAL(mouse_pos()),
this, SLOT(mouse_current_pos()));
connect(ui-> selectToolLabel, SIGNAL(mouse_pressed()),
this, SLOT(mouse_pressed()));
connect(ui-> selectToolLabel, SIGNAL(mouse_release()),
this, SLOT(mouse_release()));
connect(ui-> selectToolLabel, SIGNAL(mouse_left()),
this, SLOT(mouse_left()));
connect(ui->NewSelection, SIGNAL(pressed()),
this, SLOT(Button_New()));
connect(ui->ClearSelection, SIGNAL(pressed()),
this, SLOT(Button_clear()));
}
Dialog::~Dialog()
{
delete ui;
}//deCon
/*************************Action Buttons*******************************/
void Dialog::Button_New()
{
//- QList to store the paint obj
//-change pix color from p1 x p2 of rectangleNumber
//for loop to run a qlist
//-paint in rectangle
}
void Dialog::Button_clear()
{
//deletes all stored elements
//load originalpic
rectangleNumber = 0;
ui->selectToolLabel->storeRectanglePoints ( QPoint (0,0) , QPoint(0,0) ,
rectangleNumber );
ui->pictureLabel->imageManipulation( QPoint (0,0) , QPoint(0,0) );
ui->selectToolLabel->listOfPoints.clear ();
}
/***********************Mouse Location********************************/
void Dialog::mouse_current_pos ()
{
p3.setX (ui->selectToolLabel->x);
p3.setY (ui->selectToolLabel->y);
// ui->BoxSel->setRectanglePoints (p1,p3,Rectangle_Number);
ui->selectToolLabel->setCursor (Qt::CrossCursor);
ui->mouseCurrentPos->setText(QString
(" X = %1 , Y = %2")
.arg(p3.rx ()) //%1
.arg(p3.ry ()));//%2
update();
}//mouse_current_pos()
void Dialog::mouse_pressed()
{
//this part should be in QList with a qpair
//store it in a value and start another array for the new set
p1.setX (ui->selectToolLabel->x);
p1.setY (ui->selectToolLabel->y);
//FIXME: supposed to Draw the temp rectangle
ui->mouseCurrentEvent->setText(QString
("Mouse pressed at location %1 and %2!!!")
.arg(p1.rx ()) //%1
.arg(p1.ry ()));//%2
update();
qDebug()<<"\n Mouse key pressed \n@"
<<p1.rx ()<<p1.ry ()<<rectangleNumber;
}//mouse_pressed()
void Dialog::mouse_release()
{
rectangleNumber++;
p2.setX (ui->selectToolLabel->x);
p2.setY (ui->selectToolLabel->y);
ui->selectToolLabel->storeRectanglePoints ( p1 , p2 , rectangleNumber );
//TODO:show rectangle p1 * p2, RectangleNumber++
ui->pictureLabel->imageManipulation ( p1 , p2);//button new
ui->mouseCurrentEvent->setText(QString
("Mouse released at location %1 and %2!!!")
.arg(p2.rx ()) //%1
.arg(p2.ry ())); //%2
//save and load save
// update();
qDebug()<<"test n = "<<rectangleNumber;
}//mouse_release()
void Dialog::mouse_left()
{
ui->mouseCurrentEvent->setText("Mouse Left :( !!");
qDebug()<<"Mouse is off region \n";
}//mouse_left()
答案 0 :(得分：0)
paintEvent()总是从干净的画布开始，似乎只调用drawRect()一次。要保留所有矩形并添加另一个矩形，请将所有rects存储在列表中。在每个paintEvent()中，您将不得不遍历列表并再次绘制所有这些内容。
有很多rects，这可能会导致性能问题。在这种情况下，您还可以选择绘制到QPixmap作为类变量。在将另一个矩形绘制到像素图之后，您只需使用this将像素图绘制到drawPixmap()。