需要导入的库：

pip install PyQt5

源码：

import os
from PyQt5.QtCore import Qt, QUrl
from PyQt5.QtGui import QIcon, QPixmap
from PyQt5.QtMultimedia import QMediaPlayer, QMediaContent
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel, QSlider, QListWidget, QVBoxLayout, QWidget, QPushButton

class MusicPlayer(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Music Player")
        self.setWindowIcon(QIcon("icon.png"))
        self.resize(800, 600)

        self.current_song = None
        self.playing = False

        self.song_list_view = QListWidget()
        self.song_list_view.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)

        self.current_song_label = QLabel()
        self.current_song_label.setAlignment(Qt.AlignCenter)
        self.current_song_label.setPixmap(QPixmap("default.jpg"))

        self.progress_slider = QSlider(Qt.Horizontal)
        self.progress_slider.setEnabled(False)

        self.play_button = QPushButton()
        self.play_button.setIcon(QIcon("play.png"))
        self.play_button.clicked.connect(self.play_or_pause)

        layout = QVBoxLayout()
        layout.addWidget(self.song_list_view)
        layout.addWidget(self.current_song_label)
        layout.addWidget(self.progress_slider)
        layout.addWidget(self.play_button)

        widget = QWidget()
        widget.setLayout(layout)
        self.setCentralWidget(widget)

        self.player = QMediaPlayer()
        self.player.stateChanged.connect(self.update_playback_state)

        self.load_song_list()

    def load_song_list(self):
        song_list = os.listdir("video")
        self.song_list_view.clear()
        self.song_list_view.addItems(song_list)
        self.song_list_view.itemDoubleClicked.connect(self.play_song)

    def play_song(self, item):
        song_name = item.text()
        if self.current_song:
            self.player.stop()
            self.current_song = None
        self.player.setMedia(QMediaContent(QUrl.fromLocalFile("video/{}".format(song_name))))
        self.current_song = song_name
        self.player.play()
        self.playing = True
        self.current_song_label.setPixmap(QPixmap("video/{}.jpg".format(song_name.split(".")[0])))
        self.setWindowTitle("Music Player - {}".format(song_name.split(".")[0]))
        self.play_button.setIcon(QIcon("pause.png"))  # 更新播放按钮的图标为暂停图标

    def stop_song(self):
        self.player.stop()
        self.current_song = None
        self.playing = False
        self.current_song_label.setPixmap(QPixmap("default.jpg"))
        self.setWindowTitle("Music Player")
        self.play_button.setIcon(QIcon("play.png"))  # 更新播放按钮的图标为播放图标

    def keyPressEvent(self, event):
        if event.key() == Qt.Key_Space:
            if self.current_song:
                if self.playing:
                    self.player.pause()
                    self.playing = False
                    self.play_button.setIcon(QIcon("play.png"))  # 更新播放按钮的图标为播放图标
                else:
                    self.player.play()
                    self.playing = True
                    self.play_button.setIcon(QIcon("pause.png"))  # 更新播放按钮的图标为暂停图标

    def play_or_pause(self):
        if self.current_song:
            if self.playing:
                self.player.pause()
                self.playing = False
                self.play_button.setIcon(QIcon("play.png"))  # 更新播放按钮的图标为播放图标
            else:
                self.player.play()
                self.playing = True
                self.play_button.setIcon(QIcon("pause.png"))  # 更新播放按钮的图标为暂停图标

    def update_playback_state(self, state):
        if state == QMediaPlayer.PlayingState:
            self.playing = True
            self.setWindowTitle("Music Player - Playing")
        elif state == QMediaPlayer.PausedState:
            self.playing = False
            self.setWindowTitle("Music Player - Paused")
        elif state == QMediaPlayer.StoppedState:
            self.playing = False
            self.setWindowTitle("Music Player")

    def closeEvent(self, event):
        self.player.stop()
        event.accept()

if __name__ == "__main__":
    app = QApplication([])
    player = MusicPlayer()
    player.show()
    app.exec()

效果：

双击列表歌曲即播放。

按住下面的暂停和播放【需要图标】【空格也可以】