Error reading XML file with QT when program executes to if (!doc.setcontent (&file))

Look at Hoya's <QT creator Quick Start, and then follow the example of writing that Dom way to read an XML file out of this error.

At first everyone thought their path would be problematic, in fact, in the open before the time is not a problem, how can there be a problem in the back here? (I also have a lot of curved around here)

The other way to understand how this function works is to create a tree that stores XML-formatted data in a tree-like structure of Doc. That is, we made a mistake when we created the tree, and we could find out if our XML file was wrong by locating it.

For an XML, down the net, compare the discovery, originally the first line of <?xml Version = "1.0" encoding = "UTF-8"?> the question mark on both sides can not have spaces!

Error reading XML file with QT when program executes to if (!doc.setcontent (&file))