第4章 添加表格QTableView

1.添加table_model.py，里面子类化QAbstractTableModel，实现自定义table model

from PySide2.QtCore import Qt, QAbstractTableModel, QModelIndex
from PySide2.QtGui import QColor

#实现CustromTableModel类
class CustomTableModel(QAbstractTableModel):
    def __init__(self, data=None):
        QAbstractTableModel.__init__(self)
        self.load_data(data)

    def load_data(self, data):
        self.input_datas = data[0].values
        self.input_magnitudes = data[1].values

        self.column_count = 2
        self.row_count = len(self.input_magnitudes)

    def rowCount(self, parent=QModelIndex()):
        return self.row_count

    def columnCount(self, parent=QModelIndex()):
            return self.column_count

    def headerData(self, section, orientation, role):
        if role != Qt.DisplayRole:
            return None
        if orientation == Qt.Horizontal:
            return ("Date", "Magnitude")[section]
        else:
            return "{}".format(section)

    def data(self, index, role=Qt.DisplayRole):
        column = index.column()
        row = index.row()

        if role == Qt.DisplayRole:
            if column == 0:
                raw_data = self.input_datas[row]
                data = "{}".format(raw_data.toPython())
                return data[:-3]
            elif column == 1:
                return "{:.2f}".format(self.input_magnitudes[row])
        elif role == Qt.BackgroundRole:
           return QColor(Qt.white)
        elif role == Qt.TextAlignmentRole:
           return Qt.AlignRight

        return None

2.添加main_widget.py，使用QTableView+TableModel显示表格，设置widget布局，自适应窗口

from PySide2.QtWidgets import (QHBoxLayout, QHeaderView, QSizePolicy, QTableView, QWidget)
from table_model import *

#含TableView的窗口类
class Widget(QWidget):
    def __init__(self, data):
        QWidget.__init__(self)

        #获取model
        self.model = CustomTableModel(data)

        #创建QTableView
        self.table_view = QTableView()
        self.table_view.setModel(self.model)

        #QTableView 表头自适应以及拉伸
        self.horizontal_header = self.table_view.horizontalHeader()
        self.vertical_header = self.table_view.verticalHeader()
        self.horizontal_header.setSectionResizeMode(QHeaderView.ResizeToContents)
        self.vertical_header.setSectionResizeMode(QHeaderView.ResizeToContents)
        self.horizontal_header.setStretchLastSection(True)

        #布局
        self.main_layout = QHBoxLayout()
        size = QSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)

        #应用size策略
        size.setHorizontalStretch(1)
        self.table_view.setSizePolicy(size)
        self.main_layout.addWidget(self.table_view)

        #应用布局
        self.setLayout(self.main_layout)

3.添加main_window.py，在主窗口里使用定制好的widget

from PySide2.QtCore import Slot, qApp
from PySide2.QtGui import QKeySequence
from PySide2.QtWidgets import QMainWindow, QAction, QApplication

#主窗口
class MainWindow(QMainWindow):
    def __init__(self, widget):
        QMainWindow.__init__(self)
        self.setWindowTitle("地震信息")
        self.setCentralWidget(widget)

        # Menu
        self.menu = self.menuBar()
        self.file_menu = self.menu.addMenu("文件")

        # Exit QAction
        exit_action = QAction("退出", self)
        exit_action.setShortcut(QKeySequence.Quit)
        exit_action.triggered.connect(self.close)

        self.file_menu.addAction(exit_action)

        # Status Bar
        self.status = self.statusBar()
        self.status.showMessage("数据加载和绘制")

        # Window dimensions
        geometry = qApp.desktop().availableGeometry(self)
        self.setFixedSize(geometry.width() * 0.6, geometry.height() * 0.4)

4.添加chapter4.py，这是我们要运行的py文件，读取命令行参数，解析csv文件，将data数据传递给窗口显示

import sys, argparse
import pandas as pd
from PySide2.QtCore import QDateTime, QTimeZone

from main_widget import Widget
from main_window import MainWindow

from PySide2.QtWidgets import QApplication

def transform_date(utc, timezone=None):
    utc_fmt = "yyyy-MM-ddTHH:mm:ss.zzzZ"
    new_date = QDateTime().fromString(utc, utc_fmt)
#    print (new_date.toString(utc_fmt))
    if timezone:
        new_date.setTimeZone(timezone)

    return new_date

def read_data(fname):
    df = pd.read_csv(fname)

    #移除错误的mag
    df = df.drop(df[df.mag < 0].index)
    magnitudes = df["mag"]

    #本地时区
    timezone = QTimeZone(b"Asia/Beijing")

    #将时间戳转换为本地时区
    times = df["time"].apply(lambda x: transform_date(x, timezone))

    return times, magnitudes



if __name__ == "__main__":
    options = argparse.ArgumentParser()
    options.description = "窗口显示csv信息"
    options.add_argument("-f", "--file", type=str, required=True, help="CSV文件路径")
    args = options.parse_args()
    data = read_data(args.file)

#    print (data)
    #qt 应用
    app = QApplication(sys.argv)

    widget = Widget(data)
    window = MainWindow(widget)
    window.show()

    sys.exit(app.exec_())

5.运行效果