如何向 QWidget 添加插槽?
How to add a slot to a QWidget?
我有一个 QMainWindow,它有一个 QAction
,其信号 triggered()
连接到插槽 about2()
。
...
connect(mAboutAction2, SIGNAL(triggered()), this, SLOT(about2()));
...
void occQt::about2() //UI
{
QWidget* pWidget = new QWidget;
QPushButton* okbtn = new QPushButton(tr("ok"));
QPushButton* cancelbtn = new QPushButton(tr("cancel"));
btnlayout->addWidget(okbtn);
btnlayout->addWidget(cancelbtn);
dlglayout->setMargin(50);
dlglayout->addLayout(gridlayout);
dlglayout->addStretch(40);
dlglayout->addLayout(btnlayout);
pWidget->setLayout(dlglayout);
pWidget->setWindowTitle(tr("Make a Box by custom."));
pWidget->show();
connect(okbtn, SIGNAL(clicked()), pWidget, SLOT(make_a_box()));
connect(cancelbtn, SIGNAL(clicked()), pWidget, SLOT(close()));
}
void occQt::make_a_box()
{
TopoDS_Shape aTopoBox = BRepPrimAPI_MakeBox(3.0, 4.0, 95.0).Shape();
Handle_AIS_Shape anAisBox = new AIS_Shape(aTopoBox);
anAisBox->SetColor(Quantity_NOC_AZURE);
mContext->Display(anAisBox);
}
当我 运行 插槽 about2()
时,UI 打开。我点击cancelbtn
可以关闭,但是进不了槽make_a_box()
。
我在哪里可以添加这个槽以使这个代码工作?
没关系,运行良好,因为您使用的插槽位于正确的位置:在您的 occQt
class.
// You connect the signal FROM the action TO "this", i.e. your class
connect(mAboutAction2, SIGNAL(triggered()), this, SLOT(about2()));
void occQt::about2() //UI
{
QWidget* pWidget = new QWidget;
QPushButton* okbtn = new QPushButton(tr("ok"));
QPushButton* cancelbtn = new QPushButton(tr("cancel"));
btnlayout->addWidget(okbtn);
btnlayout->addWidget(cancelbtn);
dlglayout->setMargin(50);
dlglayout->addLayout(gridlayout);
dlglayout->addStretch(40);
dlglayout->addLayout(btnlayout);
pWidget->setLayout(dlglayout);
pWidget->setWindowTitle(tr("Make a Box by custom."));
pWidget->show();
现在,这不对:
// You connect the signal FROM the button to pWidget, which doesn't have a slot make_a_box()
connect(okbtn, SIGNAL(clicked()), pWidget, SLOT(make_a_box()));
pWidget
的插槽 make_a_box()
不存在,它是 QWidget
。您正在尝试将信号连接到不存在的插槽。
您必须在 occQt
class、 中定义此插槽,并将按钮的信号 clicked()
连接到 [=35= 中的插槽] :
// Now, you connect the signal FROM the button to "this", which is your class and has a slot make_a_box()
connect(okbtn, SIGNAL(clicked()), this, SLOT(make_a_box()));
在您的 .h 文件中,您将拥有:
private slots :
void make_a_box();
并且在您的 .cpp 文件中:
void occQt::make_a_box()
{
TopoDS_Shape aTopoBox = BRepPrimAPI_MakeBox(3.0, 4.0, 95.0).Shape();
Handle_AIS_Shape anAisBox = new AIS_Shape(aTopoBox);
anAisBox->SetColor(Quantity_NOC_AZURE);
mContext->Display(anAisBox);
}
我有一个 QMainWindow,它有一个 QAction
,其信号 triggered()
连接到插槽 about2()
。
...
connect(mAboutAction2, SIGNAL(triggered()), this, SLOT(about2()));
...
void occQt::about2() //UI
{
QWidget* pWidget = new QWidget;
QPushButton* okbtn = new QPushButton(tr("ok"));
QPushButton* cancelbtn = new QPushButton(tr("cancel"));
btnlayout->addWidget(okbtn);
btnlayout->addWidget(cancelbtn);
dlglayout->setMargin(50);
dlglayout->addLayout(gridlayout);
dlglayout->addStretch(40);
dlglayout->addLayout(btnlayout);
pWidget->setLayout(dlglayout);
pWidget->setWindowTitle(tr("Make a Box by custom."));
pWidget->show();
connect(okbtn, SIGNAL(clicked()), pWidget, SLOT(make_a_box()));
connect(cancelbtn, SIGNAL(clicked()), pWidget, SLOT(close()));
}
void occQt::make_a_box()
{
TopoDS_Shape aTopoBox = BRepPrimAPI_MakeBox(3.0, 4.0, 95.0).Shape();
Handle_AIS_Shape anAisBox = new AIS_Shape(aTopoBox);
anAisBox->SetColor(Quantity_NOC_AZURE);
mContext->Display(anAisBox);
}
当我 运行 插槽 about2()
时,UI 打开。我点击cancelbtn
可以关闭,但是进不了槽make_a_box()
。
我在哪里可以添加这个槽以使这个代码工作?
没关系,运行良好,因为您使用的插槽位于正确的位置:在您的 occQt
class.
// You connect the signal FROM the action TO "this", i.e. your class
connect(mAboutAction2, SIGNAL(triggered()), this, SLOT(about2()));
void occQt::about2() //UI
{
QWidget* pWidget = new QWidget;
QPushButton* okbtn = new QPushButton(tr("ok"));
QPushButton* cancelbtn = new QPushButton(tr("cancel"));
btnlayout->addWidget(okbtn);
btnlayout->addWidget(cancelbtn);
dlglayout->setMargin(50);
dlglayout->addLayout(gridlayout);
dlglayout->addStretch(40);
dlglayout->addLayout(btnlayout);
pWidget->setLayout(dlglayout);
pWidget->setWindowTitle(tr("Make a Box by custom."));
pWidget->show();
现在,这不对:
// You connect the signal FROM the button to pWidget, which doesn't have a slot make_a_box()
connect(okbtn, SIGNAL(clicked()), pWidget, SLOT(make_a_box()));
pWidget
的插槽 make_a_box()
不存在,它是 QWidget
。您正在尝试将信号连接到不存在的插槽。
您必须在 occQt
class、 中定义此插槽,并将按钮的信号 clicked()
连接到 [=35= 中的插槽] :
// Now, you connect the signal FROM the button to "this", which is your class and has a slot make_a_box()
connect(okbtn, SIGNAL(clicked()), this, SLOT(make_a_box()));
在您的 .h 文件中,您将拥有:
private slots :
void make_a_box();
并且在您的 .cpp 文件中:
void occQt::make_a_box()
{
TopoDS_Shape aTopoBox = BRepPrimAPI_MakeBox(3.0, 4.0, 95.0).Shape();
Handle_AIS_Shape anAisBox = new AIS_Shape(aTopoBox);
anAisBox->SetColor(Quantity_NOC_AZURE);
mContext->Display(anAisBox);
}