原文:http://zetcode.com/gui/pyqt5/widgets2/python
下面咱们继续介绍PyQt5控件。咱们将学习QPixmap, QLineEdit, QSplitter与QComboBox。web
QPixmap
是一种用于处理图像的控件。它为图片的显示作过优化。在下面的示例中,咱们将使用QPixmap展现图片。app
#!/usr/bin/python3 # -*- coding: utf-8 -*- """ ZetCode PyQt5 tutorial In this example, we dispay an image on the window. author: Jan Bodnar website: zetcode.com last edited: January 2015 """ import sys from PyQt5.QtWidgets import (QWidget, QHBoxLayout, QLabel, QApplication) from PyQt5.QtGui import QPixmap class Example(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): hbox = QHBoxLayout(self) pixmap = QPixmap("redrock.png") lbl = QLabel(self) lbl.setPixmap(pixmap) hbox.addWidget(lbl) self.setLayout(hbox) self.move(300, 200) self.setWindowTitle('Red Rock') self.show() if __name__ == '__main__': app = QApplication(sys.argv) ex = Example() sys.exit(app.exec_())
咱们在窗体中展现了一个图像。学习
pixmap = QPixmap("redrock.png")
咱们建立了一个QPixmap对象,它将传入的文件名做为参数。优化
lbl = QLabel(self) lbl.setPixmap(pixmap)
咱们将这个pixmap放到QLabel控件中。ui
QLineEdit
是用于输入或编辑单行文本的控件。它还有撤销重作、剪切复制和拖拽功能。this
#!/usr/bin/python3 # -*- coding: utf-8 -*- """ ZetCode PyQt5 tutorial This example shows text which is entered in a QLineEdit in a QLabel widget. author: Jan Bodnar website: zetcode.com last edited: January 2015 """ import sys from PyQt5.QtWidgets import (QWidget, QLabel, QLineEdit, QApplication) class Example(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): self.lbl = QLabel(self) qle = QLineEdit(self) qle.move(60, 100) self.lbl.move(60, 40) qle.textChanged[str].connect(self.onChanged) self.setGeometry(300, 300, 280, 170) self.setWindowTitle('QLineEdit') self.show() def onChanged(self, text): self.lbl.setText(text) self.lbl.adjustSize() if __name__ == '__main__': app = QApplication(sys.argv) ex = Example() sys.exit(app.exec_())
示例中展现了一个QLineEdit与一个QLabel。咱们在QLineEdit中输入的文字会实时显示在QLabel控件中。spa
qle = QLineEdit(self)
建立QLineEdit控件。3d
qle.textChanged[str].connect(self.onChanged)
若是QLineEdit控件中的文本发生变化会调用onChanged()
方法。code
def onChanged(self, text): self.lbl.setText(text) self.lbl.adjustSize()
在onChanged()
方法中咱们将QLabel控件的文本设置为输入的内容。经过调用adjustSize()
方法将QLabel控件的尺寸调整为文本的长度。
经过QSplitter
,用户能够拖动子控件边界来调整子控件的尺寸。在下面的示例中,咱们展现了三个由两个QSplitter组织的QFrame控件。
#!/usr/bin/python3 # -*- coding: utf-8 -*- """ ZetCode PyQt5 tutorial This example shows how to use QSplitter widget. author: Jan Bodnar website: zetcode.com last edited: January 2015 """ import sys from PyQt5.QtWidgets import (QWidget, QHBoxLayout, QFrame, QSplitter, QStyleFactory, QApplication) from PyQt5.QtCore import Qt class Example(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): hbox = QHBoxLayout(self) topleft = QFrame(self) topleft.setFrameShape(QFrame.StyledPanel) topright = QFrame(self) topright.setFrameShape(QFrame.StyledPanel) bottom = QFrame(self) bottom.setFrameShape(QFrame.StyledPanel) splitter1 = QSplitter(Qt.Horizontal) splitter1.addWidget(topleft) splitter1.addWidget(topright) splitter2 = QSplitter(Qt.Vertical) splitter2.addWidget(splitter1) splitter2.addWidget(bottom) hbox.addWidget(splitter2) self.setLayout(hbox) self.setGeometry(300, 300, 300, 200) self.setWindowTitle('QSplitter') self.show() def onChanged(self, text): self.lbl.setText(text) self.lbl.adjustSize() if __name__ == '__main__': app = QApplication(sys.argv) ex = Example() sys.exit(app.exec_())
示例中咱们建立了三个QFrame与两个QSplitter。注意在某些主题中这些QSplitter可能会不可见。
topleft = QFrame(self) topleft.setFrameShape(QFrame.StyledPanel)
为了观察QFrame控件间的边界,咱们使用风格化的QFrame。
splitter1 = QSplitter(Qt.Horizontal) splitter1.addWidget(topleft) splitter1.addWidget(topright)
咱们建立了一个QSplitter控件,并为它添加了两个QFrame。
splitter2 = QSplitter(Qt.Vertical) splitter2.addWidget(splitter1)
咱们也能够将QSplitter添加到另外一个QSplitter控件中。
QComboBox
是容许用户从下拉列表中进行选择的控件。
#!/usr/bin/python3 # -*- coding: utf-8 -*- """ ZetCode PyQt5 tutorial This example shows how to use a QComboBox widget. author: Jan Bodnar website: zetcode.com last edited: January 2015 """ import sys from PyQt5.QtWidgets import (QWidget, QLabel, QComboBox, QApplication) class Example(QWidget): def __init__(self): super().__init__() self.initUI() def initUI(self): self.lbl = QLabel("Ubuntu", self) combo = QComboBox(self) combo.addItem("Ubuntu") combo.addItem("Mandriva") combo.addItem("Fedora") combo.addItem("Arch") combo.addItem("Gentoo") combo.move(50, 50) self.lbl.move(50, 150) combo.activated[str].connect(self.onActivated) self.setGeometry(300, 300, 300, 200) self.setWindowTitle('QComboBox') self.show() def onActivated(self, text): self.lbl.setText(text) self.lbl.adjustSize() if __name__ == '__main__': app = QApplication(sys.argv) ex = Example() sys.exit(app.exec_())
示例中展现了一个QComboBox与一个QLabel,QComboBox控件中有5个选项(Linux系统的几个发行版名称)。QLabel控件会显示QComboBox中选中的某个选项。
combo = QComboBox(self) combo.addItem("Ubuntu") combo.addItem("Mandriva") combo.addItem("Fedora") combo.addItem("Arch") combo.addItem("Gentoo")
咱们建立了一个带有5个选项的QComboBox控件。
combo.activated[str].connect(self.onActivated)
当选中某个条目时会调用onActivated()
方法。
def onActivated(self, text): self.lbl.setText(text) self.lbl.adjustSize()
在方法中咱们将QLabel控件的内容设置为选中的条目,而后调整它的尺寸。
在这部分教程中,咱们学习了另外四个控件。