PyQt/QWebView/ScreenShotPage.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Created on 2019年7月8日
@author: Irony
@site: https://pyqt.site , https://github.com/PyQt5
@email: 892768447@qq.com
@file: ScreenShotPage
@description: 网页整体截图
"""
import base64
import cgitb
import sys

from PyQt5.QtCore import QUrl, Qt, pyqtSlot, QSize
from PyQt5.QtGui import QImage, QPainter, QIcon, QPixmap
from PyQt5.QtWebKit import QWebSettings
from PyQt5.QtWebKitWidgets import QWebView
from PyQt5.QtWidgets import QWidget, QApplication, QVBoxLayout, QPushButton, \
    QGroupBox, QLineEdit, QHBoxLayout, QListWidget, QListWidgetItem, \
    QProgressDialog

# 对部分内容进行截图
CODE = """
var el = $("%s");
html2canvas(el[0], {
    width: el.outerWidth(true), 
    windowWidth: el.outerWidth(true),
}).then(function(canvas) {
    _self.saveImage(canvas.toDataURL());
});
"""


class Window(QWidget):

    def __init__(self, *args, **kwargs):
        super(Window, self).__init__(*args, **kwargs)
        self.resize(600, 400)
        layout = QHBoxLayout(self)

        # 左侧
        widgetLeft = QWidget(self)
        layoutLeft = QVBoxLayout(widgetLeft)
        # 右侧
        self.widgetRight = QListWidget(
            self, minimumWidth=200, iconSize=QSize(150, 150))
        self.widgetRight.setViewMode(QListWidget.IconMode)
        layout.addWidget(widgetLeft)
        layout.addWidget(self.widgetRight)

        self.webView = QWebView()
        layoutLeft.addWidget(self.webView)

        # 截图方式一
        groupBox1 = QGroupBox('截图方式一', self)
        layout1 = QVBoxLayout(groupBox1)
        layout1.addWidget(QPushButton('截图1', self, clicked=self.onScreenShot1))
        layoutLeft.addWidget(groupBox1)

        # 截图方式二（采用js）
        groupBox2 = QGroupBox('截图方式二', self)
        layout2 = QVBoxLayout(groupBox2)
        self.codeEdit = QLineEdit(
            'body', groupBox2, placeholderText='请输入需要截图的元素、ID或者class：如body、#id .class')
        layout2.addWidget(self.codeEdit)
        self.btnMethod2 = QPushButton(
            '', self, clicked=self.onScreenShot2, enabled=False)
        layout2.addWidget(self.btnMethod2)
        layoutLeft.addWidget(groupBox2)

        # 开启开发人员工具
        QWebSettings.globalSettings().setAttribute(
            QWebSettings.DeveloperExtrasEnabled, True)
        self.webView.loadStarted.connect(self.onLoadStarted)
        self.webView.loadFinished.connect(self.onLoadFinished)
        self.webView.load(QUrl("https://pyqt.site"))

        # 暴露接口和加载完成后执行jquery等一些库文件
        self.webView.page().mainFrame().javaScriptWindowObjectCleared.connect(
            self.populateJavaScriptWindowObject)

    def populateJavaScriptWindowObject(self):
        self.webView.page().mainFrame().addToJavaScriptWindowObject(
            '_self', self)

    def onLoadStarted(self):
        print('load started')
        self.btnMethod2.setEnabled(False)
        self.btnMethod2.setText('暂时无法使用（等待页面加载完成）')

    def onLoadFinished(self):
        # 注入脚本
        mainFrame = self.webView.page().mainFrame()
        # 执行jquery,promise,html2canvas
        mainFrame.evaluateJavaScript(
            open('Data/jquery.js', 'rb').read().decode())
        mainFrame.evaluateJavaScript(
            open('Data/promise-7.0.4.min.js', 'rb').read().decode())
        mainFrame.evaluateJavaScript(
            open('Data/html2canvas.min.js', 'rb').read().decode())
        print('inject js ok')
        self.btnMethod2.setText('截图2')
        self.btnMethod2.setEnabled(True)

    def onScreenShot1(self):
        # 截图方式1
        page = self.webView.page()
        frame = page.mainFrame()
        size = frame.contentsSize()
        image = QImage(size, QImage.Format_ARGB32_Premultiplied)
        image.fill(Qt.transparent)

        painter = QPainter()
        painter.begin(image)
        painter.setRenderHint(QPainter.Antialiasing, True)
        painter.setRenderHint(QPainter.TextAntialiasing, True)
        painter.setRenderHint(QPainter.SmoothPixmapTransform, True)

        # 记录旧大小
        oldSize = page.viewportSize()
        # *****重点就是这里******
        page.setViewportSize(size)
        frame.render(painter)
        painter.end()

        # 截图完成后需要还原,否则界面不响应鼠标等
        page.setViewportSize(oldSize)

        # 添加到左侧list中
        item = QListWidgetItem(self.widgetRight)
        image = QPixmap.fromImage(image)
        item.setIcon(QIcon(image))
        item.setData(Qt.UserRole + 1, image)

    def onScreenShot2(self):
        # 截图方式2
        code = self.codeEdit.text().strip()
        if not code:
            return
        self.progressdialog = QProgressDialog(self, windowTitle='正在截图中')
        self.progressdialog.setRange(0, 0)
        self.webView.page().mainFrame().evaluateJavaScript(CODE % code)
        self.progressdialog.exec_()

    @pyqtSlot(str)
    def saveImage(self, image):
        self.progressdialog.close()
        # data:image/png;base64,iVBORw0KG....
        if not image.startswith('data:image'):
            return
        data = base64.b64decode(image.split(';base64,')[1])
        image = QPixmap()
        image.loadFromData(data)
        # 添加到左侧list中
        item = QListWidgetItem(self.widgetRight)
        item.setIcon(QIcon(image))
        item.setData(Qt.UserRole + 1, image)


if __name__ == "__main__":
    cgitb.enable(format='text')
    app = QApplication(sys.argv)
    w = Window()
    w.show()
    sys.exit(app.exec_())