如何添加一个插槽到QWidget？ [英] How to add a slot to a QWidget?

问题描述

我有一个QMainWindow，它有一个 QAction 的信号 triggered（）连接到一个插槽 about2（）。

I have a QMainWindow, which has a QAction whose signal triggered() is connected to a slot 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 about2 code>，UI打开。我可以在点击 cancelbtn 时关闭它，但我无法输入 make_a_box（）。

When I run the slot about2(), the UI opens. I can close it when I click the cancelbtn, but I can't enter the slot make_a_box().

我可以在哪里添加此广告位，以使此代码正常运行？

推荐答案

这是确定和运行良好，因为您使用的插槽位于正确的位置：在 occQt 类。 / p>

This is ok and runs fine, because the slot you are using is located at the right place : in your 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，这不行：

 // 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()));

插槽 make_a_box（）存在 pWidget ，这是一个 QWidget 。您尝试将信号连接到不存在的插槽。

The slot make_a_box() doesn't exist for pWidget, which is a QWidget. You are trying to connect a signal to a slot that does not exist.

您必须在 occQt class ，并将按钮的信号 clicked（）连接到您课程中的插槽：

You have to define this slot in your occQt class, and connect the signal clicked() of the button to your slot in your class :

// 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，您将有：

In your .h file, you will have :

private slots : 
    void make_a_box();

在您的.cpp文件中：

And in your .cpp file :

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);
}

这篇关于如何添加一个插槽到QWidget？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！