8.3 KiB
对话框
对话框是一个现代GUI应用不可或缺的一部分。对话是两个人之间的交流，对话框就是人与电脑之间的对话。对话框用来输入数据，修改数据，修改应用设置等等。
QInputDialog
QInputDialog提供了一个简单方便的对话框，可以输入字符串，数字或列表。
#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
ZetCode PyQt5 tutorial
In this example, we receive data from
a QInputDialog dialog.
author: Jan Bodnar
website: zetcode.com
last edited: January 2015
"""
import sys
from PyQt5.QtWidgets import (QWidget, QPushButton, QLineEdit,
QInputDialog, QApplication)
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.btn = QPushButton('Dialog', self)
self.btn.move(20, 20)
self.btn.clicked.connect(self.showDialog)
self.le = QLineEdit(self)
self.le.move(130, 22)
self.setGeometry(300, 300, 290, 150)
self.setWindowTitle('Input dialog')
self.show()
def showDialog(self):
text, ok = QInputDialog.getText(self, 'Input Dialog',
'Enter your name:')
if ok:
self.le.setText(str(text))
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
这个示例有一个按钮和一个输入框，点击按钮显示对话框，输入的文本会显示在输入框里。
text, ok = QInputDialog.getText(self, 'Input Dialog',
'Enter your name:')
这是显示一个输入框的代码。第一个参数是输入框的标题，第二个参数是输入框的占位符。对话框返回输入内容和一个布尔值，如果点击的是OK按钮，布尔值就返回True。
if ok:
self.le.setText(str(text))
把得到的字符串放到输入框里。
程序展示：
QColorDialog
QColorDialog提供颜色的选择。
#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
ZetCode PyQt5 tutorial
In this example, we select a color value
from the QColorDialog and change the background
color of a QFrame widget.
author: Jan Bodnar
website: zetcode.com
last edited: January 2015
"""
import sys
from PyQt5.QtWidgets import (QWidget, QPushButton, QFrame,
QColorDialog, QApplication)
from PyQt5.QtGui import QColor
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
col = QColor(0, 0, 0)
self.btn = QPushButton('Dialog', self)
self.btn.move(20, 20)
self.btn.clicked.connect(self.showDialog)
self.frm = QFrame(self)
self.frm.setStyleSheet("QWidget { background-color: %s }"
% col.name())
self.frm.setGeometry(130, 22, 100, 100)
self.setGeometry(300, 300, 250, 180)
self.setWindowTitle('Color dialog')
self.show()
def showDialog(self):
col = QColorDialog.getColor()
if col.isValid():
self.frm.setStyleSheet("QWidget { background-color: %s }"
% col.name())
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
例子里有一个按钮和一个QFrame，默认的背景颜色为黑色，我们可以使用QColorDialog改变背景颜色。
col = QColor(0, 0, 0)
初始化QtGui.QFrame的背景颜色。
col = QColorDialog.getColor()
弹出一个QColorDialog对话框。
if col.isValid():
self.frm.setStyleSheet("QWidget { background-color: %s }"
% col.name())
我们可以预览颜色，如果点击取消按钮，没有颜色值返回，如果颜色是我们想要的，就从取色框里选择这个颜色。
程序展示：
todo：截图
QFontDialog
QFontDialog能做字体的选择。
#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
ZetCode PyQt5 tutorial
In this example, we select a font name
and change the font of a label.
author: Jan Bodnar
website: zetcode.com
last edited: January 2015
"""
import sys
from PyQt5.QtWidgets import (QWidget, QVBoxLayout, QPushButton,
QSizePolicy, QLabel, QFontDialog, QApplication)
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
vbox = QVBoxLayout()
btn = QPushButton('Dialog', self)
btn.setSizePolicy(QSizePolicy.Fixed,
QSizePolicy.Fixed)
btn.move(20, 20)
vbox.addWidget(btn)
btn.clicked.connect(self.showDialog)
self.lbl = QLabel('Knowledge only matters', self)
self.lbl.move(130, 20)
vbox.addWidget(self.lbl)
self.setLayout(vbox)
self.setGeometry(300, 300, 250, 180)
self.setWindowTitle('Font dialog')
self.show()
def showDialog(self):
font, ok = QFontDialog.getFont()
if ok:
self.lbl.setFont(font)
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
我们创建了一个有一个按钮和一个标签的QFontDialog的对话框，我们可以使用这个功能修改字体样式。
font, ok = QFontDialog.getFont()
弹出一个字体选择对话框。getFont()方法返回一个字体名称和状态信息。状态信息有OK和其他两种。
if ok:
self.label.setFont(font)
如果点击OK，标签的字体就会随之更改。
程序展示：
QFileDialog
QFileDialog给用户提供文件或者文件夹选择的功能。能打开和保存文件。
#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
ZetCode PyQt5 tutorial
In this example, we select a file with a
QFileDialog and display its contents
in a QTextEdit.
author: Jan Bodnar
website: zetcode.com
last edited: January 2015
"""
import sys
from PyQt5.QtWidgets import (QMainWindow, QTextEdit,
QAction, QFileDialog, QApplication)
from PyQt5.QtGui import QIcon
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.textEdit = QTextEdit()
self.setCentralWidget(self.textEdit)
self.statusBar()
openFile = QAction(QIcon('open.png'), 'Open', self)
openFile.setShortcut('Ctrl+O')
openFile.setStatusTip('Open new File')
openFile.triggered.connect(self.showDialog)
menubar = self.menuBar()
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(openFile)
self.setGeometry(300, 300, 350, 300)
self.setWindowTitle('File dialog')
self.show()
def showDialog(self):
fname = QFileDialog.getOpenFileName(self, 'Open file', '/home')
if fname[0]:
f = open(fname[0], 'r')
with f:
data = f.read()
self.textEdit.setText(data)
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())
The example shows a menubar, centrally set text edit widget, and a statusbar. The menu item shows the QtGui.QFileDialog which is used to select a file. The contents of the file are loaded into the text edit widget.
class Example(QMainWindow):
def __init__(self):
super().__init__()
self.initUI()
The example is based on the QMainWindow widget because we centrally set a text edit widget.
fname = QFileDialog.getOpenFileName(self, 'Open file', '/home')
We pop up the QFileDialog. The first string in the getOpenFileName() method is the caption. The second string specifies the dialog working directory. By default, the file filter is set to All files (*).
if fname[0]:
f = open(fname[0], 'r')
with f:
data = f.read()
self.textEdit.setText(data)
The selected file name is read and the contents of the file are set to the text edit widget.
程序展示：
