QtWebkit synchronous loading
c++, qt, qtwebkit
Solution
If anyone's interested, I implemented this using a special "PageRasterizer" class.
The class creates a QWebPage in the constructor and sets a bool loading flag to false. A `connect()` call connects the `loadFinished` signal to a member slot that merely sets the loading flag to true.
A special `RenderPage()` member function that returns an image does all the work: it accepts the HTML string and calls `setHtml()`. After that comes a `while` loop that waits on the flag; while the flag is false, `qApp->processEvents()` is called so signals get emitted and the flag setting slot is eventually called. When it is, the loop breaks and now you can render the page to a QImage (don't forget to set the flag back to false before returning).
If you're interested in the rendering process, look at this Qt example (the `Thumbnailer::render()` function).
For bonus points, you can make this class a functor.
Problem
I'm using a QWebPage without a QWebView because I want to render the contents of an HTML file onto a QPixmap/QImage. I want the loading of the page to be done synchronously, not asynchronously which is the default. The default way is to call `QWebFrame::setHtml()` or `QWebFrame::setContent()`, but this loads images asynchronously. What I want is some sort of blocking function call, something like `QWebFrame::waitUntilLoadFinished()` after which I could just call `render()` and be done with it. I can't find a way to do this. Am I missing something?