qpainter

问题 I'm trying to make an app where you can draw with your finger on a canvas. To achieve this, I'm subclassing QWidget as MFCanvas , registered the class in QML with qmlRegisterType<>() , implementing the virtual paintEvent(); function, and drawing on it with a QPainter inside the paintEvent(); function. The Problem: Upon construction, the QPainter throws this warning: QWidget::paintEngine: Should no longer be called Then, serveral other related warnings are thrown: QPainter::begin: Paint device

问题 I'm new on Qt and c++, so I'm having some difficulties. I'm trying to create a widget that can get the mouseMoveEvent position and draw an ellipse on my pixmap on mouse position. Below you can see the code: #include "myimage.h" #include <QPainter> #include <QPen> #include <QColor> #include <QMouseEvent> #include <QDebug> Myimage::Myimage(QWidget *parent) : QWidget(parent) { setMouseTracking(true); // E.g. set in your constructor of your widget. } // Implement in your widget void Myimage:

问题 I'm new on Qt and c++, so I'm having some difficulties. I'm trying to create a widget that can get the mouseMoveEvent position and draw an ellipse on my pixmap on mouse position. Below you can see the code: #include "myimage.h" #include <QPainter> #include <QPen> #include <QColor> #include <QMouseEvent> #include <QDebug> Myimage::Myimage(QWidget *parent) : QWidget(parent) { setMouseTracking(true); // E.g. set in your constructor of your widget. } // Implement in your widget void Myimage:

问题 I'm new on Qt and c++, so I'm having some difficulties. I'm trying to create a widget that can get the mouseMoveEvent position and draw an ellipse on my pixmap on mouse position. Below you can see the code: #include "myimage.h" #include <QPainter> #include <QPen> #include <QColor> #include <QMouseEvent> #include <QDebug> Myimage::Myimage(QWidget *parent) : QWidget(parent) { setMouseTracking(true); // E.g. set in your constructor of your widget. } // Implement in your widget void Myimage:

问题 My application draws a 3D rendering to an offline QImage (without OpenGL for historical reasons) and then draws that QImage in a widget like this: void Render3dModel::paintEvent(QPaintEvent *event) { // Update model and render new image m_model.calculate(); QImage image = m_model.getImage(); // Draw image in widget QPainter painter(this); painter.drawImage(QPointF(0, 0), image); } The image gets repainted based on mouse movements using QWidget::update(): void Render3dModel::mouseMoveEvent

问题 I have this code import sys import os from PyQt5.QtWidgets import * from PyQt5.QtGui import * DIR_PATH = os.path.dirname(os.path.realpath(__file__)) class ThinLabel(QLabel): def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) def paintEvent(self, event): qp = QPainter(self) qp.setRenderHint(QPainter.Antialiasing) path = QPainterPath() path.addText(event.rect().bottomLeft(), self.font(), self.text()) qp.setPen(QPen(self.palette().color(QPalette.Window), 2)) qp.setBrush(self

问题 This question already has an answer here : Drawing with a brush (1 answer) Closed 2 years ago . Python 3, latest version of PyQt5 on Mac OS Mojave I want a PyQt5 program in which the user could paint connected dots on an image (click distinctively and the points are automatically connected). It is important that I can only draw on the image in the QLabel widget (or an alternative widget) and not over the entire main window. I can plot the image and get the the coordinates of the previous two

问题 I'm printing a set of tables, each table should get its own page and could be long. The basics are working, but I don't get the footer painted. The problem is the footer will be painted in an extra document(s). According to the docs I must set the painter to the device. The device is painter, that's correct, but how do I set the painter to the correct Block? Or is it wrong to act this way? The goal is to use this document twice. 1st attempt is to print, the second a QTextDocument where I can

问题 I'm printing a set of tables, each table should get its own page and could be long. The basics are working, but I don't get the footer painted. The problem is the footer will be painted in an extra document(s). According to the docs I must set the painter to the device. The device is painter, that's correct, but how do I set the painter to the correct Block? Or is it wrong to act this way? The goal is to use this document twice. 1st attempt is to print, the second a QTextDocument where I can

问题 I'm printing a set of tables, each table should get its own page and could be long. The basics are working, but I don't get the footer painted. The problem is the footer will be painted in an extra document(s). According to the docs I must set the painter to the device. The device is painter, that's correct, but how do I set the painter to the correct Block? Or is it wrong to act this way? The goal is to use this document twice. 1st attempt is to print, the second a QTextDocument where I can