本文介绍了我如何在另一个线程Qt中显示MessageBox的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

这是我的代码:

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    testApp w;
    w.show();
    TestClass *test = new TestClass;
    QObject::connect(w.ui.pushButton, SIGNAL(clicked()), test, SLOT(something()));
    return a.exec();
}

TestClass.h

TestClass.h

class TestClass: public QObject
{
    Q_OBJECT
    public slots:
        void something()
        {
            TestThread *thread = new TestThread;

            thread -> start();
        }

};

TestThread.h

TestThread.h

class TestThread: public QThread
{
    Q_OBJECT
protected:
    void run()
    {
        sleep(1000);
        QMessageBox Msgbox;
        Msgbox.setText("Hello!");
        Msgbox.exec();
    }

};

如果我这样做,我会看到错误

If i'm doing this, i see error

我做错了什么?请帮我.我知道我不能在另一个线程中更改gui,但是我不知道在qt中的构造.

What am I doing wrong? Please help me. I know that I cant change gui in another thread, but i dont know constuctions in qt for this.

推荐答案

您正试图在非GUI线程中显示小部件.

You are trying to show widget in non-gui thread.

class TestClass: public QObject
{
    Q_OBJECT
    public slots:
        void something()
        {
            TestThread *thread = new TestThread();

            // Use Qt::BlockingQueuedConnection !!!
            connect( thread, SIGNAL( showMB() ), this, SLOT( showMessageBox() ), Qt::BlockingQueuedConnection ) ;

            thread->start();
        }
        void showMessageBox()
        {
            QMessageBox Msgbox;
            Msgbox.setText("Hello!");
            Msgbox.exec();
        }
};


class TestThread: public QThread
{
    Q_OBJECT
signals:
    void showMB();
protected:
    void run()
    {
        sleep(1);
        emit showMB();
    }

};

这篇关于我如何在另一个线程Qt中显示MessageBox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!

05-29 03:12
查看更多