mainwindow.cpp Example File

webenginewidgets/stylesheetbrowser/mainwindow.cpp
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 #include "mainwindow.h"
 #include "stylesheetdialog.h"
 #include "ui_mainwindow.h"

 static QMap<QString, QString> defaultStyleSheets = {
     {"Upside down", "body { -webkit-transform: rotate(180deg); }"}
 };

 MainWindow::MainWindow(const QUrl &url) :
     QMainWindow(),
     ui(new Ui::MainWindow)
 {
     ui->setupUi(this);

     connect(ui->urlBar, &QLineEdit::returnPressed, this, &MainWindow::urlEntered);
     connect(ui->webEngineView, &QWebEngineView::urlChanged, this, &MainWindow::urlChanged);
     connect(ui->settingsButton, &QPushButton::clicked, this, &MainWindow::showStyleSheetsDialog);
     connect(ui->reloadButton, &QPushButton::clicked, this, &MainWindow::reloadRequested);

     QSettings settings;
     settings.beginGroup("styleSheets");
     QStringList styleSheets = settings.allKeys();
     if (styleSheets.empty()) {
         // Add back default style sheets if the user cleared them out
         loadDefaultStyleSheets();
     } else {
         for (auto name : qAsConst(styleSheets)) {
             StyleSheet styleSheet = settings.value(name).value<StyleSheet>();
             if (styleSheet.second)
                 insertStyleSheet(name, styleSheet.first, false);
         }
     }
     settings.endGroup();

     ui->webEngineView->setUrl(url);
 }

 MainWindow::~MainWindow()
 {
     delete ui;
 }

 void MainWindow::insertStyleSheet(const QString &name, const QString &source, bool immediately)
 {
     QWebEngineScript script;
     QString s = QString::fromLatin1("(function() {"\
                                     "    css = document.createElement('style');"\
                                     "    css.type = 'text/css';"\
                                     "    css.id = '%1';"\
                                     "    document.head.appendChild(css);"\
                                     "    css.innerText = '%2';"\
                                     "})()").arg(name).arg(source.simplified());
     if (immediately)
         ui->webEngineView->page()->runJavaScript(s, QWebEngineScript::ApplicationWorld);

     script.setName(name);
     script.setSourceCode(s);
     script.setInjectionPoint(QWebEngineScript::DocumentReady);
     script.setRunsOnSubFrames(true);
     script.setWorldId(QWebEngineScript::ApplicationWorld);
     ui->webEngineView->page()->scripts().insert(script);
 }

 void MainWindow::removeStyleSheet(const QString &name, bool immediately)
 {
     QString s = QString::fromLatin1("(function() {"\
                                     "    var element = document.getElementById('%1');"\
                                     "    element.outerHTML = '';"\
                                     "    delete element;"\
                                     "})()").arg(name);
     if (immediately)
         ui->webEngineView->page()->runJavaScript(s, QWebEngineScript::ApplicationWorld);

     QWebEngineScript script = ui->webEngineView->page()->scripts().findScript(name);
     ui->webEngineView->page()->scripts().remove(script);
 }

 bool MainWindow::hasStyleSheet(const QString &name)
 {
     QWebEngineScript script = ui->webEngineView->page()->scripts().findScript(name);
     return !script.isNull();
 }

 void MainWindow::loadDefaultStyleSheets()
 {
     QSettings settings;
     settings.beginGroup("styleSheets");

     auto it = defaultStyleSheets.constBegin();
     while (it != defaultStyleSheets.constEnd()) {
         settings.setValue(it.key(), QVariant::fromValue(qMakePair(it.value(), true)));
         insertStyleSheet(it.key(), it.value(), false);
         ++it;
     }

     settings.endGroup();
 }

 void MainWindow::urlEntered()
 {
     ui->webEngineView->setUrl(QUrl::fromUserInput(ui->urlBar->text()));
 }

 void MainWindow::urlChanged(const QUrl &url)
 {
     ui->urlBar->setText(url.toString());
 }

 void MainWindow::showStyleSheetsDialog()
 {
     StylesheetDialog *dialog = new StylesheetDialog(this);
     dialog->show();
 }

 void MainWindow::reloadRequested()
 {
     ui->webEngineView->reload();
 }