python - QCompleter supporting multiple items like stackoverflow tag field

Question

Is there a way to make the QCompleter for pyside work more similar to how the Tag editor here on StackOverflow works? Where a user can type a word and then if there is a space it allows the autocomplete to display matching words?

This post seems like it does what i want but it's in C++ How to force QCompleter to check second word in QLineEdit

import os
import sys
import json
from PySide import QtCore, QtGui


class ExampleWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(ExampleWindow, self).__init__(parent)
        self.resize(300, 200)

        self.strings_model = QtGui.QStringListModel()
        self.get_data(self.strings_model)
        completer = QtGui.QCompleter()
        completer.setCaseSensitivity(QtCore.Qt.CaseInsensitive)
        completer.setModel(self.strings_model)

        self.ui_input = QtGui.QLineEdit()
        self.ui_input.setCompleter(completer)
        self.ui_input.setPlaceholderText('enter description...')

        self.ui_tags_list = QtGui.QListView()
        self.ui_tags_list.setEditTriggers(QtGui.QAbstractItemView.NoEditTriggers)
        self.ui_tags_list.setSelectionMode(QtGui.QAbstractItemView.ExtendedSelection)
        self.ui_tags_list.setModel(self.strings_model)


        # main layout
        main_layout = QtGui.QVBoxLayout()
        main_layout.setContentsMargins(5,5,5,5)
        main_layout.setSpacing(5)
        main_layout.addWidget(self.ui_input)
        main_layout.addWidget(self.ui_tags_list)

        main_widget = QtGui.QWidget()
        main_widget.setLayout(main_layout)
        self.setCentralWidget(main_widget)

        # connections
        self.ui_input.returnPressed.connect(self.input_entered)


    def get_data(self, model):
        model.setStringList(["Animals", "Dogs", "Birds", "Cats", "Elephant", "Zebra"])


    def append_tag(self, val):
        if not val:
            return False

        if val.lower() in [x.lower() for x in self.strings_model.stringList()]:
            return False

        self.strings_model.insertRow(self.strings_model.rowCount())
        index = self.strings_model.index(self.strings_model.rowCount()-1)
        self.strings_model.setData(index, val)


    def input_entered(self):
        print 'selected word from drop down should be added to lineEdit'


def main():
    app = QtGui.QApplication(sys.argv)
    ex = ExampleWindow()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

Answer 1

You must implement a logic that gets the last string, this will be the word to make the filter in the QComplete through setCompletionPrefix():

class LineEdit(QtGui.QLineEdit):
    def __init__(self, *args, **kwargs):
        QtGui.QLineEdit.__init__(self, *args, **kwargs)
        self.multipleCompleter = None

    def keyPressEvent(self, event):
        QtGui.QLineEdit.keyPressEvent(self, event)
        if not self.multipleCompleter:
            return
        c = self.multipleCompleter
        if self.text() == "":
            return
        c.setCompletionPrefix(self.cursorWord(self.text()))
        if len(c.completionPrefix()) < 1:
            c.popup().hide()
            return
        c.complete()

    def cursorWord(self, sentence):
        p = sentence.rfind(" ")
        if p == -1:
            return sentence
        return sentence[p + 1:]

    def insertCompletion(self, text):
        p = self.text().rfind(" ")
        if p == -1:
            self.setText(text)
        else:
            self.setText(self.text()[:p+1]+ text)

    def setMultipleCompleter(self, completer):
        self.multipleCompleter = completer
        self.multipleCompleter.setWidget(self)
        completer.activated.connect(self.insertCompletion)


def main():
    app = QtGui.QApplication(sys.argv)
    w = LineEdit()
    completer = QtGui.QCompleter(["Animals", "Dogs", "Birds", "Cats", "Elephant", "Zebra"])
    completer.setCaseSensitivity(QtCore.Qt.CaseInsensitive)
    w.setMultipleCompleter(completer)
    w.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()