Source code for GUI.ErrorTab.ErrorWidget

from PyQt5 import QtCore
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPixmap, QFont
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QLabel, QHBoxLayout, QPushButton, QFrame
from datetime import datetime


class ErrorWidget(QWidget):
    """
        :Inherit: :class:`QWidget`

        :Description:
            Error widget is used to indicate state of binary variable.\n
            States are as follow:
            1. OK -> Green LED
            2. No data -> Yellow LED
            3. Error -> Red Led

        :param name: The name of the variable it signals.
        :type name: str

        :param id: CAN ID used to identify where data should be send.
        :param id: str
    """

    ICONS = {
        "Green": "Images/green_led.png",
        "Red": "Images/red_led.png",
        "Yellow": "Images/yellow_led.png"
    }

    update_signal = QtCore.pyqtSignal(float)

    def __init__(self, name, id):
        QWidget.__init__(self)

        self.name = name
        self.id = id
        self.status = None
        self.locked = False

        self.update_signal.connect(self.update_data)

        layout = QVBoxLayout()

        img = QPixmap(self.ICONS["Yellow"])
        self.icon = QLabel()
        self.icon.setPixmap(img)
        self.icon.setAlignment(Qt.AlignCenter)
        layout.addWidget(self.icon)

        # Name label
        self.name_label = QLabel(self.name)
        self.name_label.setStyleSheet("color: rgb(255,255,255);"
                                      "font: bold \"MS Shell\"; "
                                      "font-size: 9; "
                                      "qproperty-alignment: AlignCenter;")
        self.name_label.setWordWrap(True)
        layout.addWidget(self.name_label)

        # Error layout
        self.error_frame = QFrame()
        error_layout = QHBoxLayout()

        self.time_label = QLabel("")
        self.time_label.setFixedSize(65, 21)
        self.time_label.setStyleSheet("color: rgb(255,0,0);"
                                      "font: \"MS Shell\";"
                                      "font-size: 9;"
                                      "qproperty-alignment: AlignCenter;")
        error_layout.addWidget(self.time_label, alignment=Qt.AlignRight | Qt.AlignHCenter)

        self.reset_button = QPushButton("Reset")
        self.reset_button.setFixedSize(70, 21)
        self.reset_button.setStyleSheet("color: rgb(255,0,0); "
                                        "font: bold \"MS Shell\"; "
                                        "font-size: 9")
        self.reset_button.clicked.connect(self.error_reset)
        error_layout.addWidget(self.reset_button, alignment=Qt.AlignLeft | Qt.AlignHCenter)

        self.error_frame.setLayout(error_layout)
        layout.addWidget(self.error_frame)

        self.setLayout(layout)
        self.error_frame.hide()

    def update_data(self, status):
        """
            :Description:
                Updates status and show appropriate signalization LED.

            :param status: New status value.
            :type status: bool
        """
        if not self.locked and self.status != status:
            self.status = status
            if bool(self.status):
                img = QPixmap(self.ICONS["Red"])
                self.error_received()
            else:
                img = QPixmap(self.ICONS["Green"])

            self.icon.setPixmap(img)

    def error_received(self):
        """
            :Description:
                Used when error status is received.\n
                Shows time of error and reset button.\n
                Locks widget do new states won't change anything.
        """
        timestamp = datetime.now().strftime("%H:%M:%S")
        self.time_label.setText(timestamp)

        self.name_label.setStyleSheet("color: rgb(255, 0, 0);"
                                      "font: bold \"MS Shell\"; "
                                      "font-size: 9; "
                                      "qproperty-alignment: AlignCenter;")
        self.error_frame.show()
        self.locked = True

    def error_reset(self):
        """
            :Description:
                Event handler for reset button click.\n
                Hide reset button and timestamp.\n
                Sets icon to yellow.\n
                Unlock widget and set state to None.
        """
        img = QPixmap(self.ICONS["Yellow"])
        self.icon.setPixmap(img)

        self.name_label.setStyleSheet("color: rgb(255, 255, 255);"
                                      "font: bold \"MS Shell\"; "
                                      "font-size: 9; "
                                      "qproperty-alignment: AlignCenter;")
        self.error_frame.hide()
        self.locked = False
        self.status = None