python - 在 Qt Designer 中使用自定义 PySide2 小部件
问题描述
我正在寻找一种在 Qt Designer 中有效地使用 Qt for Python (PySide2) 编写的自定义小部件的方法。
我发现,可以使用基本小部件设计 GUI,然后只需将类换成 UI 文件中的自定义小部件并通知QUiLoader
子类loader.registerCustomWidget(MyMainWindow)
,然后在 Qt Designer 中再次打开它不起作用那好吧。
我在PyQt 的类似问题中读到,您必须为自定义小部件编写插件。PySide2 是否也存在这种可能性?
一些示例代码:
custom_widget.py:
import sys
from PySide2.QtUiTools import QUiLoader
from PySide2.QtWidgets import QApplication, QMainWindow, QAction, QMessageBox, QFileDialog, QTextBrowser
from PySide2.QtCore import QFile
class MyMainWindow(QMainWindow):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.setWindowTitle("Demo QtWidget App")
def closeEvent(self, event):
msgBox = QMessageBox()
msgBox.setWindowTitle("Quit?")
msgBox.setText("Exit application?")
msgBox.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
msgBox.setDefaultButton(QMessageBox.No)
ret = msgBox.exec_()
if ret == QMessageBox.Yes:
event.accept()
else:
event.ignore()
if __name__ == '__main__':
app = QApplication([])
file = QFile("custom_widget_original.ui")
#file = QFile("custom_widget_modified.ui")
file.open(QFile.ReadOnly)
loader = QUiLoader()
loader.registerCustomWidget(MyMainWindow)
main_window = loader.load(file)
main_window.show()
sys.exit(app.exec_())
custom_widget_original.ui
使用此版本,应用程序将毫无疑问地关闭。
<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="QMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>600</height>
</rect>
</property>
<property name="windowTitle">
<string>MainWindow</string>
</property>
<widget class="QWidget" name="centralwidget">
<layout class="QGridLayout" name="gridLayout">
<item row="0" column="0">
<widget class="QLabel" name="label_2">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="2">
<widget class="QLabel" name="label">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="1">
<widget class="QLabel" name="label_3">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
</layout>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>21</height>
</rect>
</property>
<widget class="QMenu" name="menuFile">
<property name="title">
<string>File</string>
</property>
<addaction name="actionExit"/>
</widget>
<addaction name="menuFile"/>
</widget>
<widget class="QStatusBar" name="statusbar"/>
<action name="actionExit">
<property name="text">
<string>Exit</string>
</property>
</action>
</widget>
<resources/>
<connections>
<connection>
<sender>actionExit</sender>
<signal>triggered()</signal>
<receiver>MainWindow</receiver>
<slot>close()</slot>
<hints>
<hint type="sourcelabel">
<x>-1</x>
<y>-1</y>
</hint>
<hint type="destinationlabel">
<x>399</x>
<y>299</y>
</hint>
</hints>
</connection>
</connections>
</ui>
custom_widget_modified.ui
在此版本中,系统会询问您是否真的要退出。
<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="MyMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>600</height>
</rect>
</property>
<property name="windowTitle">
<string>MainWindow</string>
</property>
<widget class="QWidget" name="centralwidget">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>155</width>
<height>15</height>
</rect>
</property>
<layout class="QGridLayout" name="gridLayout">
<item row="0" column="0">
<widget class="QLabel" name="label_2">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="2">
<widget class="QLabel" name="label">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="1">
<widget class="QLabel" name="label_3">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
</layout>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>21</height>
</rect>
</property>
<widget class="QMenu" name="menuFile">
<property name="title">
<string>File</string>
</property>
<addaction name="actionExit"/>
</widget>
<addaction name="menuFile"/>
</widget>
<widget class="QStatusBar" name="statusbar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>3</width>
<height>18</height>
</rect>
</property>
</widget>
<action name="actionExit">
<property name="text">
<string>Exit</string>
</property>
</action>
</widget>
<customwidgets>
<customwidget>
<class>MyMainWindow</class>
<extends>QWidget</extends>
<header>mymainwindow.h</header>
<container>1</container>
</customwidget>
</customwidgets>
<resources/>
<connections>
<connection>
<sender>actionExit</sender>
<signal>triggered()</signal>
<receiver>MainWindow</receiver>
<slot>close()</slot>
<hints>
<hint type="sourcelabel">
<x>-1</x>
<y>-1</y>
</hint>
<hint type="destinationlabel">
<x>399</x>
<y>299</y>
</hint>
</hints>
</connection>
</connections>
</ui>
该<customwidgets>
段在再次打开后由 Qt 设计器添加。
修改后 Qt Designer 没有正确放置三个标签。
解决方案
在 Qt Designer 中使用自定义小部件有两种主要方法:
1. 推广小部件:
这是最简单、最省力的方法,如果它是一个内部小部件,您只需右键单击该小部件并选择Promote To ...,然后在:
- 基类名称选择您继承的类
- 提升类名称放置类的名称
- 头文件放置将扩展名 .py 更改为 .h 的文件的路径
以上所做的是生成以下内容:
...
<widget class="RadialBar" name="widget" native="true"/>
...
<customwidgets>
<customwidget>
<class>RadialBar</class>
<extends>QWidget</extends>
<header>radialbar.h</header>
<container>1</container>
</customwidget>
</customwidgets>
...
即更改类,在customwidget中添加一个字段指向类的名称:<class> NAME_OF_CLASS </class>
,它们继承的类的名称<extends>CLASS_EXTENDS</extends>
和文件路径将文件扩展名从.py更改为.h <header>PATH_OF_FILE.h</header>
,即与您输入的数据相同表格。
在根小部件的情况下,它不能通过 Qt Designer 完成,但我看到你已经理解了逻辑,但你没有正确修改所有内容,你的主要错误是指出它们继承的类
<customwidgets>
<customwidget>
<class>MyMainWindow</class>
<extends>QMainWindow</extends> <----
<header>mymainwindow.h</header>
<container>1</container>
</customwidget>
</customwidgets>
所以正确的文件是:
custom_widget_modified.ui
<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="MyMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>600</height>
</rect>
</property>
<property name="windowTitle">
<string>MainWindow</string>
</property>
<widget class="QWidget" name="centralwidget">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>155</width>
<height>15</height>
</rect>
</property>
<layout class="QGridLayout" name="gridLayout">
<item row="0" column="0">
<widget class="QLabel" name="label_2">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="2">
<widget class="QLabel" name="label">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
<item row="0" column="1">
<widget class="QLabel" name="label_3">
<property name="text">
<string>TextLabel</string>
</property>
</widget>
</item>
</layout>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>800</width>
<height>21</height>
</rect>
</property>
<widget class="QMenu" name="menuFile">
<property name="title">
<string>File</string>
</property>
<addaction name="actionExit"/>
</widget>
<addaction name="menuFile"/>
</widget>
<widget class="QStatusBar" name="statusbar">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>3</width>
<height>18</height>
</rect>
</property>
</widget>
<action name="actionExit">
<property name="text">
<string>Exit</string>
</property>
</action>
</widget>
<customwidgets>
<customwidget>
<class>MyMainWindow</class>
<extends>QMainWindow</extends>
<header>mymainwindow.h</header>
<container>1</container>
</customwidget>
</customwidgets>
<resources/>
<connections>
<connection>
<sender>actionExit</sender>
<signal>triggered()</signal>
<receiver>MainWindow</receiver>
<slot>close()</slot>
<hints>
<hint type="sourcelabel">
<x>-1</x>
<y>-1</y>
</hint>
<hint type="destinationlabel">
<x>399</x>
<y>299</y>
</hint>
</hints>
</connection>
</connections>
</ui>
我的主窗口.py
import sys
from PySide2.QtUiTools import QUiLoader
from PySide2.QtWidgets import QApplication, QMainWindow, QMessageBox
from PySide2.QtCore import QFile
class MyMainWindow(QMainWindow):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.setWindowTitle("Demo QtWidget App")
def closeEvent(self, event):
msgBox = QMessageBox()
msgBox.setWindowTitle("Quit?")
msgBox.setText("Exit application?")
msgBox.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
msgBox.setDefaultButton(QMessageBox.No)
ret = msgBox.exec_()
if ret == QMessageBox.Yes:
event.accept()
else:
event.ignore()
if __name__ == '__main__':
app = QApplication([])
file = QFile("custom_widget_modified.ui")
file.open(QFile.ReadOnly)
loader = QUiLoader()
loader.registerCustomWidget(MyMainWindow)
main_window = loader.load(file)
main_window.show()
sys.exit(app.exec_())