PySide2

Question

希望有人能帮助我，因为我找不到任何在线可用的东西。

我正在为 AI 项目构建一个简单的 GUI，并使用 PySide2 和 QML。我已经设法理解如何将一个函数绑定到一个按钮并使其工作。但我似乎无法弄清楚如何从 python 字符串列表中填充组合框（然后使用 python 中的选择）。我知道它与属性和模型有关，但我无法让它工作。

这是我的 python 代码：


import multiprocessing as mp
import sys

import mido
from Fuzzy.aidrummer import AiDrummer

from PySide2.QtWidgets import QApplication
from PySide2.QtQuick import QQuickView
from PySide2.QtCore import QUrl, Slot, QObject, Property, Signal

def run():
    d = AiDrummer('playback', file='../Music/28 coltrane 2.mid', play_instrument='yes', instrument_port='VirtualMIDISynth #1 0',
                  out_port='strike 3', visualize=True)
    d.run()


class Api(QObject):
    proc = None

    def __init__(self):
        QObject.__init__(self)
        self._midi_out = mido.get_output_names()
        print(self._midi_out)
        self._midi_in = mido.get_input_names()

    @Slot()
    def play(self):
        self.proc = mp.Process(target=run)
        self.proc.start()

    @Slot()
    def stop(self):
        try:
            assert isinstance(self.proc, mp.Process)
            self.proc.kill()
        except:
            return

    def read_midi_out(self):
        return self._midi_out

    def set_midi_out(self, val):
        self._midi_out = val

    @Signal
    def midi_out_changed(self):
        pass

    midi_out = Property(list, read_midi_out, set_midi_out, notify=midi_out_changed)


if __name__ == '__main__':
    app = QApplication([])
    view = QQuickView()
    view.setResizeMode(QQuickView.SizeRootObjectToView)
    url = QUrl("main.qml")

    api = Api()

    view.setSource(url)
    view.rootContext().setContextProperty('api', api)

    sys.exit(app.exec_())

还有我的main.qml（带模型的组合框靠近底部）：

import QtQuick 2.12
import QtQuick.Window 2.12
import QtQuick.Controls 2.13
import QtQuick.Controls.Material 2.0

Window {
    id: window
    visible: true
    width: 980
    height: 700
    title: qsTr("AI Drummer")

    Rectangle {
        id: rectangle1
        color: "#191919"
        anchors.rightMargin: 0
        anchors.bottomMargin: 0
        anchors.leftMargin: 0
        anchors.topMargin: 0
        anchors.fill: parent
        clip: true
        rotation: 0

        Rectangle {
            id: rectangle
            x: 711
            width: 400
            height: 200
            color: "#3a3a3a"
            anchors.top: parent.top
            anchors.topMargin: -33
            anchors.right: parent.right
            anchors.rightMargin: -131
            rotation: 45
            clip: true
            Material.theme: Material.Dark
            Material.accent: Material.DeepOrange
        }

        RoundButton {
            id: playButton
            x: 356
            y: 632
            width: 100
            text: "Play"
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 28
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 70
            onClicked: { api.play()}
        }

        RoundButton {
            id: stopButton
            x: 462
            y: 632
            width: 100
            text: "Stop"
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 28
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: -70
            onClicked: { api.stop()}
        }

        ComboBox {
            id: instrument_port
            x: 214
            y: 637
            width: 120
            height: 30
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 176
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 33
        }

        ComboBox {
            id: out_port
            x: 68
            y: 637
            width: 120
            height: 30
            anchors.bottomMargin: 33
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 302
            anchors.bottom: parent.bottom
            model: api.midi_out
        }
    }
    Connections {
        target: api
    }
}

Answer 1

您的代码存在以下错误：

midi_out 属性只能读取和通知，因为您不能编写（创建）MIDI 设备，所以不要实现 setter。
midi设备的名称只是在开头获取。如果连接了其他设备？我将不得不关闭并重新打开应用程序，而是添加了允许更新设备名称的 "reload()" 函数。
如果根元素是Window或ApplicationWindow那么你必须使用QQmlApplicationEngine，如果它是一个Item那么你必须使用QQuickView。
如果您想在 PySide2 中导出为属性列表，您必须使用 QVariantList ⁽¹⁾

import multiprocessing as mp

import mido

from Fuzzy.aidrummer import AiDrummer

from PySide2.QtWidgets import QApplication
from PySide2.QtQml import QQmlApplicationEngine
from PySide2.QtCore import QUrl, Slot, QObject, Property, Signal


def run():
    d = AiDrummer(
        "playback",
        file="../Music/28 coltrane 2.mid",
        play_instrument="yes",
        instrument_port="VirtualMIDISynth #1 0",
        out_port="strike 3",
        visualize=True,
    )
    d.run()


class Api(QObject):
    midi_in_names_Changed = Signal()
    midi_out_names_Changed = Signal()

    def __init__(self, parent=None):
        super().__init__(parent)

        self.proc = None
        self.reload()

    @Slot()
    def reload(self):
        self._midi_in_names = mido.get_input_names()
        self._midi_out_names = mido.get_output_names()
        self.midi_in_names_Changed.emit()
        self.midi_out_names_Changed.emit()

    def get_midi_in_names(self):
        return self._midi_in_names

    def get_midi_out_names(self):
        return self._midi_out_names

    midi_in_names = Property(
        "QVariantList", fget=get_midi_in_names, notify=midi_in_names_Changed
    )
    midi_out_names = Property(
        "QVariantList", fget=get_midi_out_names, notify=midi_out_names_Changed
    )

    @Slot()
    def play(self):
        self.proc = mp.Process(target=run)
        self.proc.start()

    @Slot()
    def stop(self):
        self.proc.kill()


if __name__ == "__main__":
    import os
    import sys

    app = QApplication(sys.argv)

    api = Api()

    engine = QQmlApplicationEngine()
    engine.rootContext().setContextProperty("api", api)

    current_dir = os.path.dirname(os.path.realpath(__file__))

    url = QUrl.fromLocalFile(os.path.join(current_dir, "main.qml"))

    engine.load(url)

    if not engine.rootObjects():
        sys.exit(-1)

    sys.exit(app.exec_())

import QtQuick 2.12
import QtQuick.Window 2.12
import QtQuick.Controls 2.13
import QtQuick.Controls.Material 2.0

Window {
    id: window
    visible: true
    width: 980
    height: 700
    title: qsTr("AI Drummer")

    Rectangle {
        id: rectangle1
        color: "#191919"
        anchors.rightMargin: 0
        anchors.bottomMargin: 0
        anchors.leftMargin: 0
        anchors.topMargin: 0
        anchors.fill: parent
        clip: true
        rotation: 0

        Rectangle {
            id: rectangle
            x: 711
            width: 400
            height: 200
            color: "#3a3a3a"
            anchors.top: parent.top
            anchors.topMargin: -33
            anchors.right: parent.right
            anchors.rightMargin: -131
            rotation: 45
            clip: true
            Material.theme: Material.Dark
            Material.accent: Material.DeepOrange
        }

        RoundButton {
            id: playButton
            x: 356
            y: 632
            width: 100
            text: "Play"
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 28
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 70
            onClicked: { api.play()}
        }

        RoundButton {
            id: stopButton
            x: 462
            y: 632
            width: 100
            text: "Stop"
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 28
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: -70
            onClicked: { api.stop()}
        }

        ComboBox {
            id: instrument_port
            x: 214
            y: 637
            width: 120
            height: 30
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 176
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 33
        }

        ComboBox {
            id: out_port
            x: 68
            y: 637
            width: 120
            height: 30
            anchors.bottomMargin: 33
            anchors.right: parent.horizontalCenter
            anchors.rightMargin: 302
            anchors.bottom: parent.bottom
            model: api.midi_out_names
        }
    }
}

⁽¹⁾

PySide2 - 要查看的绑定模型

PySide2 - Binding model to view

python

qt

qml