我正在尝试将 qt 示例从 C++ 移植到 pyqt/pyside2。此示例使用 QPropertyAnimation 显示带有文本编辑字段的隐藏/显示操作。
看起来并不复杂,但我还是想不通为什么不能正常工作
主要思想是:文本编辑小部件通过按下 ">" 按钮“折叠”,并在再次按下按钮时返回。
这是我的 python 代码:
import PySide2
from PySide2.QtWidgets import *
from PySide2.QtCore import *
from PySide2.QtGui import *
import sys
class myWidget(QWidget):
def __init__(self):
super(myWidget, self).__init__()
self.m_deltaX = 0
self.m_isClosed = False
self.btn = QPushButton(self)
self.btn.setText(">")
self.btn.setCheckable(True)
self.btn.setFixedSize(QSize(25, 25))
self.btn.connect(SIGNAL("clicked()"), self.closeOpenEditor)
self.text1 = QTextEdit(self)
self.text1.setText("some sample text")
self.text2 = QTextEdit(self)
self.layout_btn = QVBoxLayout()
self.layout_btn.addWidget(self.btn)
self.layout_m = QHBoxLayout()
self.layout_m.addWidget(self.text1, 10)
self.layout_m.addSpacing(15)
self.layout_m.addLayout(self.layout_btn)
self.layout_m.setSpacing(0)
self.layout_m.addWidget(self.text2, 4)
self.setLayout(self.layout_m)
self.resize(800, 500)
def closeOpenEditor(self):
self.m_isClosed = self.btn.isChecked()
animation1 = QPropertyAnimation(self.text2, b"geometry")
if self.m_isClosed:
self.text2.setMaximumWidth(self.text2.width())
text2Start = int(self.text2.maximumWidth())
self.m_deltaX = text2Start
text2End = int(3)
animation1.setDuration(250)
animation1.setStartValue(text2Start)
animation1.setEndValue(text2End)
self.btn.setText("<")
else:
text2Start = int(self.text2.maximumWidth())
text2End = int(self.m_deltaX)
animation1.setDuration(250)
animation1.setStartValue(text2Start)
animation1.setEndValue(text2End)
self.btn.setText(">")
animation1.start()
def resizeEvent(self, event:QResizeEvent):
if not self.m_isClosed:
self.text2.setMaximumWidth(QWIDGETSIZE_MAX)
if __name__ == '__main__':
app = QApplication(sys.argv)
w = myWidget()
w.show()
sys.exit(app.exec_())
我还将添加 C++ 代码:
主窗口.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QTextEdit>
#include <QPushButton>
#include <QHBoxLayout>
class MyWidget : public QWidget
{
Q_OBJECT
QTextEdit *m_textEditor1;
QTextEdit *m_textEditor2;
QPushButton *m_pushButton;
QHBoxLayout *m_layout;
QVBoxLayout *m_buttonLayout;
int m_deltaX;
bool m_isClosed;
public:
MyWidget(QWidget * parent = 0);
~MyWidget(){}
void resizeEvent( QResizeEvent * event );
private slots:
void closeOrOpenTextEdit2(bool isClosing);
};
#endif // MAINWINDOW_H
main.cpp
#include <mainwindow.h>
#include <QPropertyAnimation>
#include <QApplication>
#include <QIcon>
MyWidget::MyWidget(QWidget * parent):QWidget(parent),m_deltaX(0)
{
m_pushButton = new QPushButton(this);
m_pushButton->setText(">");
m_pushButton->setCheckable(true);
m_pushButton->setFixedSize(25,25);
//m_pushButton->setStyleSheet("background-color: yellow;");
connect(m_pushButton, SIGNAL(clicked(bool)), this, SLOT(closeOrOpenTextEdit2(bool)));
m_textEditor1 = new QTextEdit(this);
m_textEditor1->setText("И рвется в пляс душа моя, головой я выбиваю дверцы...");
m_textEditor2 = new QTextEdit(this);
m_buttonLayout = new QVBoxLayout();
m_buttonLayout->addWidget(m_pushButton);
m_buttonLayout->addItem( new QSpacerItem(1, 1, QSizePolicy::Minimum, QSizePolicy::Expanding) );
m_layout = new QHBoxLayout;
m_layout->addWidget(m_textEditor1, 10);
m_layout->addSpacing(15);
m_layout->addLayout(m_buttonLayout);
m_layout->setSpacing(0);
m_layout->addWidget(m_textEditor2, 4);
setLayout(m_layout);
resize(800,500);
}
void MyWidget::closeOrOpenTextEdit2(bool isClosing)
{
m_isClosed = isClosing;
QPropertyAnimation *animation1 = new QPropertyAnimation(m_textEditor2, "maximumWidth");
if(isClosing) //close the second textEdit
{
m_textEditor2->setMaximumWidth(m_textEditor2->width());
int textEdit2_start = m_textEditor2->maximumWidth();
m_deltaX = textEdit2_start;
int textEdit2_end = 3;
animation1->setDuration(250);
animation1->setStartValue(textEdit2_start);
animation1->setEndValue(textEdit2_end);
m_pushButton->setText("<");
}
else //open
{
int textEdit2_start = m_textEditor2->maximumWidth();
int textEdit2_end = m_deltaX;
animation1->setDuration(250);
animation1->setStartValue(textEdit2_start);
animation1->setEndValue(textEdit2_end);
m_pushButton->setText(">");
//m_pushButton->setIcon()
}
animation1->start();
}
void MyWidget::resizeEvent( QResizeEvent * event )
{
if(!m_isClosed)
m_textEditor2->setMaximumWidth( QWIDGETSIZE_MAX );
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MyWidget w;
w.show();
return a.exec();
}
在我重写的代码中,它不想启动动画。你应该按两次按钮,然后它会永久折叠小部件,没有任何动画。所以你不能再打开它。
我还收到了一些错误:
QPropertyAnimation::updateState (geometry, QTextEdit, ): starting an animation without end value
和
NameError: name 'QWIDGETSIZE_MAX' is not defined
最佳答案
您的代码有以下错误:
在 C++ 代码中修改的属性是 maximumWidth 但在您的 python 代码中您使用的是 geometry,在 maximumWidth 的情况下,需要一个整数,但 geometry 需要一个 QRect,因此您会收到错误消息,因为 endValue 是类型不正确,因此无法通过注意到它没有建立值来建立。
在 Python 中,局部变量在其作用域结束时将被删除,但在 PyQt 中,如果局部变量是一个 QObject,并且具有另一个具有更大作用域的 QObject 作为父对象,则除外。在C++的情况下除了使用parent来延长生命周期外就是使用指针。
QWIDGETSIZE_MAX 未在 PySide2 中定义(但它在 PyQt5 中定义:
QtWidgets.QWIDGETSIZE_MAX
)因此您必须定义一个变量,该变量采用它在 C++ 中采用的值。
from PySide2 import QtCore, QtWidgets
# https://code.qt.io/cgit/qt/qtbase.git/tree/src/widgets/kernel/qwidget.h#n873
QWIDGETSIZE_MAX = (1 << 24) - 1
class MyWidget(QtWidgets.QWidget):
def __init__(self):
super(MyWidget, self).__init__()
self.m_deltaX = 0
self.btn = QtWidgets.QPushButton(
">", checkable=True, clicked=self.closeOpenEditor
)
self.btn.setFixedSize(QtCore.QSize(25, 25))
self.text1 = QtWidgets.QTextEdit()
self.text1.setText("some sample text")
self.text2 = QtWidgets.QTextEdit()
layout_btn = QtWidgets.QVBoxLayout()
layout_btn.addWidget(self.btn)
lay = QtWidgets.QHBoxLayout(self)
lay.addWidget(self.text1, 10)
lay.addSpacing(15)
lay.addLayout(layout_btn)
lay.setSpacing(0)
lay.addWidget(self.text2, 4)
self.resize(800, 500)
self.m_animation = QtCore.QPropertyAnimation(
self.text2, b"maximumWidth", parent=self, duration=250
)
def closeOpenEditor(self):
if self.btn.isChecked():
self.text2.setMaximumWidth(self.text2.width())
text2Start = int(self.text2.maximumWidth())
self.m_deltaX = text2Start
text2End = 3
self.m_animation.setStartValue(text2Start)
self.m_animation.setEndValue(text2End)
self.btn.setText("<")
else:
text2Start = int(self.text2.maximumWidth())
text2End = self.m_deltaX
self.m_animation.setStartValue(text2Start)
self.m_animation.setEndValue(text2End)
self.btn.setText(">")
self.m_animation.start()
def resizeEvent(self, event: "QResizeEvent"):
if not self.btn.isChecked():
self.text2.setMaximumWidth(QWIDGETSIZE_MAX)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
w = MyWidget()
w.show()
sys.exit(app.exec_())
关于python - 如何修复 QPropertyAnimation "starting an animation without end value"错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56654339/