Mastering GUI Programming with Python

The SlowSearcher file search engine

In order to talk effectively about threading, we first require a slow process that can be run on a separate thread. Open a new copy of the Qt application template and call it file_searcher.py.

Let's begin by implementing a file searching engine:

class SlowSearcher(qtc.QObject):    match_found = qtc.pyqtSignal(str)    directory_changed = qtc.pyqtSignal(str)    finished = qtc.pyqtSignal()    def __init__(self):        super().__init__()        self.term = None

We're calling this SlowSearcher because it's going to be deliberately non-optimized. It starts with defining a few signals, as follows:

• The match_found signal will be emitted when a filename matches the search term and will contain the matched filename
• The directory_changed ...