PyQt5（16）对话框QDialog普通对话框、消息对话框（用于报错）字体对话框用于字体调节，文件对话框，文件的打开和读取

'''

对话框：QDialog普通对话框

QMessageBox
QColorDialog
QFileDialog打开或者保存
QFontDialog
QInputDialog

QMainWindow
QWidget
QDialog

'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class QDialogDemo(QMainWindow):
    def __init__(self):
        super(QDialogDemo,self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('QDialog案例')
        self.resize(300,200)

        self.button = QPushButton(self)
        self.button.setText('弹出对话框')
        self.button.move(50,50)
        self.button.clicked.connect(self.showDialog)

    def showDialog(self):
        dialog = QDialog()
        button = QPushButton('确定',dialog)
        button.clicked.connect(dialog.close)
        button.move(50,50)
        dialog.setWindowTitle('对话框')
        dialog.setWindowModality(Qt.ApplicationModal)

        dialog.exec()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QDialogDemo()
    main.show()
    sys.exit(app.exec_())

'''

消息对话框：QMessageBox


1. 关于对话框
2. 错误对话框
3. 警告对话框
4. 提问对话框
5. 消息对话框


有2点差异
1. 显示的对话框图标可能不同
2. 显示的按钮是不一样的

'''
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class QMessageBoxDemo(QWidget):
    def __init__(self):
        super(QMessageBoxDemo,self).__init__()
        self.initUI()
    def initUI(self):
        self.setWindowTitle('QMessageBox案例')
        self.resize(300,400)

        layout = QVBoxLayout()
        self.button1 = QPushButton()
        self.button1.setText('显示关于对话框')
        self.button1.clicked.connect(self.showDialog)

        self.button2 = QPushButton()
        self.button2.setText('显示消息对话框')
        self.button2.clicked.connect(self.showDialog)

        self.button3 = QPushButton()
        self.button3.setText('显示警告对话框')
        self.button3.clicked.connect(self.showDialog)


        self.button4 = QPushButton()
        self.button4.setText('显示错误对话框')
        self.button4.clicked.connect(self.showDialog)

        self.button5 = QPushButton()
        self.button5.setText('显示提问对话框')
        self.button5.clicked.connect(self.showDialog)


        layout.addWidget(self.button1)
        layout.addWidget(self.button2)
        layout.addWidget(self.button3)
        layout.addWidget(self.button4)
        layout.addWidget(self.button5)
        self.setLayout(layout)

    def showDialog(self):
        text = self.sender().text()
        if text == '显示关于对话框':
            QMessageBox.about(self,'关于','这是一个关于对话框')
        elif text == '显示消息对话框':
            reply = QMessageBox.information(self,'消息','这是一个消息对话框', QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)#第三个表示直接按回车会进行的选择
            print(reply == QMessageBox.Yes)
        elif text == '显示警告对话框':
            QMessageBox.warning(self,'警告','这是一个警告对话框',QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)
        elif text == '显示错误对话框':
            QMessageBox.critical(self,'警告','这是一个警告对话框',QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)
        elif text == '显示提问对话框':
            QMessageBox.question(self,'警告','这是一个警告对话框',QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QMessageBoxDemo()
    main.show()
    sys.exit(app.exec_())

'''

字体对话框：QFontDialog



'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class QFontDialogDemo(QWidget):
    def __init__(self):
        super(QFontDialogDemo,self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('Font Dialog例子')
        layout = QVBoxLayout()
        self.fontButton = QPushButton('选择字体')
        self.fontButton.clicked.connect(self.getFont)
        layout.addWidget(self.fontButton)

        self.fontLabel = QLabel('Hello，测试字体例子')
        layout.addWidget(self.fontLabel)

        self.setLayout(layout)
    def getFont(self):
        font, ok = QFontDialog.getFont()
        if ok :
            self.fontLabel.setFont(font)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QFontDialogDemo()
    main.show()
    sys.exit(app.exec_())

'''

颜色对话框：QColorDialog

'''


import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class QColorDialogDemo(QWidget):
    def __init__(self):
        super(QColorDialogDemo,self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('Color Dialog例子')
        layout = QVBoxLayout()
        self.colorButton = QPushButton('设置颜色')
        self.colorButton.clicked.connect(self.getColor)
        layout.addWidget(self.colorButton)

        self.colorButton1 = QPushButton('设置背景颜色')
        self.colorButton1.clicked.connect(self.getBGColor)
        layout.addWidget(self.colorButton1)

        self.colorLabel = QLabel('Hello，测试颜色例子')
        layout.addWidget(self.colorLabel)

        self.setLayout(layout)
    def getColor(self):
        color = QColorDialog.getColor()
        p = QPalette()#是一个调色板
        p.setColor(QPalette.WindowText,color)
        self.colorLabel.setPalette(p)
    def getBGColor(self):
        color = QColorDialog.getColor()
        p = QPalette()
        p.setColor(QPalette.Window,color)
        self.colorLabel.setAutoFillBackground(True)
        self.colorLabel.setPalette(p)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QColorDialogDemo()
    main.show()
    sys.exit(app.exec_())

'''

文件对话框：QFileDialog

'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class QFileDialogDemo(QWidget):
    def __init__(self):
        super(QFileDialogDemo,self).__init__()
        self.initUI()

    def initUI(self):
        layout = QVBoxLayout()
        self.button1 = QPushButton('加载图片')
        self.button1.clicked.connect(self.loadImage)
        layout.addWidget(self.button1)

        self.imageLabel = QLabel()
        layout.addWidget(self.imageLabel)

        self.button2 = QPushButton('加载文本文件')
        self.button2.clicked.connect(self.loadText)
        layout.addWidget(self.button2)

        self.contents = QTextEdit()
        layout.addWidget(self.contents)

        self.setLayout(layout)
        self.setWindowTitle('文件对话框演示 ')

    def loadImage(self):
        fname,_ = QFileDialog.getOpenFileName(self,'打开文件','.','图像文件(*.jpg *.png)')#取消不需要指示用下划线
        self.imageLabel.setPixmap(QPixmap(fname))

    def loadText(self):
        dialog = QFileDialog()
        dialog.setFileMode(QFileDialog.AnyFile)
        dialog.setFilter(QDir.Files)#过滤选择文件

        if dialog.exec():
            filenames = dialog.selectedFiles()
            f = open(filenames[0],encoding='utf-8',mode='r')
            with f:
                data = f.read()
                self.contents.setText(data)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = QFileDialogDemo()
    main.show()
    sys.exit(app.exec_())