learnxinyminutes-docs/pyqt.html.markdown

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---
category: framework
framework: PyQT
filename: learnpyqt.py
contributors:
- ["Nathan Hughes", "https://github.com/sirsharpest"]
---
**Qt** is a widely-known framework for developing cross-platform software that can be run on various software and hardware platforms with little or no change in the code, while having the power and speed of native applications. Though **Qt** was originally written in *C++*.
This is an adaption on the C++ intro to QT by [Aleksey Kholovchuk](https://github.com/vortexxx192
), some of the code examples should result in the same functionality
this version just having been done using pyqt!
```python
import sys
from PyQt4 import QtGui
def window():
# Create an application object
app = QtGui.QApplication(sys.argv)
# Create a widget where our label will be placed in
w = QtGui.QWidget()
# Add a label to the widget
b = QtGui.QLabel(w)
# Set some text for the label
b.setText("Hello World!")
# Give some size and placement information
w.setGeometry(100, 100, 200, 50)
b.move(50, 20)
# Give our window a nice title
w.setWindowTitle("PyQt")
# Have everything display
w.show()
# Execute what we have asked for, once all setup
sys.exit(app.exec_())
if __name__ == '__main__':
window()
```
In order to get some of the more advanced features in **pyqt** we need to start looking at building additional elements.
Here we show how to introduce a dialog popup box, useful for asking the user to confirm a decision or to provide information.
```python
import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
def window():
app = QApplication(sys.argv)
w = QWidget()
# Create a button and attach to widget w
b = QPushButton(w)
b.setText("Press me")
b.move(50, 50)
# Tell b to call this function when clicked
# notice the lack of "()" on the function call
b.clicked.connect(showdialog)
w.setWindowTitle("PyQt Dialog")
w.show()
sys.exit(app.exec_())
# This function should create a dialog window with a button
# that waits to be clicked and then exits the program
def showdialog():
d = QDialog()
b1 = QPushButton("ok", d)
b1.move(50, 50)
d.setWindowTitle("Dialog")
# This modality tells the popup to block the parent whilst it's active
d.setWindowModality(Qt.ApplicationModal)
# On click I'd like the entire process to end
b1.clicked.connect(sys.exit)
d.exec_()
if __name__ == '__main__':
window()
```