python interactive output with Qt4

[eegrek39]

I am trying to print a fibonacci sequence in a QTextEdit box in Qt4 and I am only getting the last number. How do I print the whole sequence my code is

class MyApp(QtGui.QMainWindow, Ui_MainWindow):
def __init__(self):
QtGui.QMainWindow.__init__(self)
Ui_MainWindow.__init__(self)
self.setupUi(self)
self.runButton.clicked.connect(self.calculate)

## Fibonacci sequence code
def calculate(self):

a, b = 0, 1

while b < 10:

t = str(b)
output = t
self.outputText.setText(output)

a, b = b, a+b




if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
window = MyApp()
window.show()
sys.exit(app.exec_())