The structure of a QT Application
A basic QT Application (with a widget)
You will create your first Window in this application.
#!/usr/bin/env python import sys from PyQt4.QtGui import * from PyQt4.QtCore import * app = QApplication(sys.argv) win = QWidget() win.show() sys.exit(app.exec_())
Did you notice the differences? You did less and got more. But don’t let this fool you. KDE requires this information, but from now on, i doesn’t get any more complicated in KDE than in pure Qt.
Maybe you did spot what we did now and didn’t do earlier: We constructed a widget and showed it. Clicking on the standard “x”-button it closes the whole application by default, but you can change that, of course. You can now transfer the widget-code into the KDE application but you wouldn’t want to write KDE applications if you didn’t want to use KDE’s features, do you?
Let’s move on, but without wasting space: I will leave out everything redundant now, you should keep it in your script, though. Everything we care about now is what we can do between these two lines:
win = QWidget() win.show()
What about using our window as a frame for other widgets?
In order to do that, we will need a so-called layout and add our widgets to it:
win = QWidget() layout = QVBoxLayout() layout.addWidget(QLabel("This is a Label showing text,<br> but it can contain a Picture instead")) layout.addWidget(QPushButton("Push me")) win.setLayout(layout) win.show()
What have we done? Quite something, I guess. We have:
- Created and shown our widget, as we did before
- Created a layout which stacks widgets vertically (VBox) and told the widget to use it
- Added two more widgets to it, both containing text. (As you can see, the QLabel even supports HTML-stuff like the <br>-linebreak)