Use QThread to periodically update a QTableWidget pyqt

问题

In my application, I'm fetching records using an API call and then I add the data to a QTableWidget dynamically. Here is a snippet of my code so far:

class TriageUI(QtGui.QMainWindow):
    def __init__(self):
        QtGui.QMainWindow.__init__(self)
        self.ui = Ui_TriageWindow()
        self.setWindowFlags(QtCore.Qt.WindowStaysOnTopHint)
        self.move(QtGui.QApplication.desktop().screen().rect().center()- self.rect().center())
        self.ui.setupUi(self)
        self.update_records()        

    def update_records(self):
        #items are the results from the API fetch
        items = json.loads(get_triage_queue(COOKIES, SERVER, PORT))
        rows = len(items['objects'])
        self.ui.tableWidget.setColumnCount(5)
        self.ui.tableWidget.setRowCount(rows)
        index = 0
        column = 0
        for j in items['objects']:
            for key, value in j.iteritems():
                f = QtGui.QTableWidgetItem(str(value))
                self.ui.tableWidget.setItem(index, column, QtGui.QTableWidgetItem(f))
                column = column + 1

However, I want to be able to make the API call for data periodically(e.g after 15 seconds) and then add any new data items in the results to the table. How can I achieve this.

Thank you in advance.

回答1:

Here you have an example of doing repetitive calls to a class member function (that could be your update_records function) using a PyQt4.QtCore.QTimer. Some times the solution to a problem is more easy than we think.

Note the functions start and stop. This functions makes you able to start and stop the timer at your will.

from PyQt4 import QtGui as gui
from PyQt4 import QtCore as core


class Blinker(gui.QWidget):
    def __init__(self, parent=None):
        super(Blinker, self).__init__(parent)

        self.label = gui.QLabel(self)
        self.label.setFixedSize(200, 200)
        self.layout = gui.QHBoxLayout(self)
        self.layout.addWidget(self.label)

        self.timer  = core.QTimer(self)
        self.timer.setInterval(1000)          # Throw event timeout with an interval of 1000 milliseconds
        self.timer.timeout.connect(self.blink) # each time timer counts a second, call self.blink
        self.color_flag = True

    def start(self):
        self.timer.start()

    def stop(self):
        self.timer.stop()

    @core.pyqtSlot()
    def blink(self):
        if self.color_flag:
            self.label.setStyleSheet("background-color: blue;")
        else:
            self.label.setStyleSheet("background-color: yellow;")
        self.color_flag = not self.color_flag


if __name__ == '__main__':
    import sys
    app = gui.QApplication(sys.argv)

    w = Blinker()
    w.show()
    w.start()

    sys.exit(app.exec_())

来源：https://stackoverflow.com/questions/23786340/use-qthread-to-periodically-update-a-qtablewidget-pyqt

标签

python

pyqt

pyqt4

qtablewidget