QT 实时数据更新UI

水深无声 2022-12-20 01:54 245阅读 0赞

main.cpp

#include "mainwindow.h"
    #include <QApplication>
    
    int main(int argc, char *argv[])
    { 
        QApplication a(argc, argv);
        MainWindow w;
        w.show();
    
        return a.exec();
    }

mainwindow.h

#ifndef MAINWINDOW_H
    #define MAINWINDOW_H
    
    #include <QMainWindow>
    #include "workthread.h"
    
    namespace Ui { 
    class MainWindow;
    }
    
    class MainWindow : public QMainWindow
    { 
        Q_OBJECT
    
    public:
        explicit MainWindow(QWidget *parent = 0);
        ~MainWindow();
    
    public slots:
        void showValue(int value);// 显示槽函数
    
    private slots:
        void on_StartBtn_clicked();// 开始按钮槽函数
        void on_StopBtn_clicked(); // 结束按钮槽函数
    
    private:
        Ui::MainWindow *ui;
    
    private:
        WorkThread * workThread;
    };
    
    #endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
    #include "ui_mainwindow.h"
    
    MainWindow::MainWindow(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::MainWindow)
    { 
        ui->setupUi(this);
        ui->value->setText("0");// label显示文本
    }
    
    MainWindow::~MainWindow()
    { 
        delete ui;
    }
    
    void MainWindow::showValue(int value)
    { 
        //ui->value->setText("ttt");// label显示文本
        ui->value->setText(QString::number(value)); //更新label内容
    }
    
    void MainWindow::on_StartBtn_clicked()
    { 
        workThread = new WorkThread();
        workThread->start();
        connect(workThread, SIGNAL(currentValue_signal(int)), this, SLOT(showValue(int)));
        ui->StartBtn->setEnabled(false);
        ui->StopBtn->setEnabled(true);
    }
    
    void MainWindow::on_StopBtn_clicked()
    { 
        workThread->terminate();
        workThread->wait();
    
        ui->StartBtn->setEnabled(true);
        ui->StopBtn->setEnabled(false);
    }

workthread.h

#ifndef WORKTHREAD_H
    #define WORKTHREAD_H
    
    #include <QThread>
    
    class WorkThread:public QThread
    { 
        Q_OBJECT
    
    public:
        WorkThread();
        ~WorkThread();
        // 重写run()方法
        void run();
    signals:
        void currentValue_signal(int value);// 定义信号发到主线程
    };
    
    #endif // WORKTHREAD_H

workthread.cpp

#include "workthread.h"
    #include <QDebug>
    
    WorkThread::WorkThread()
    { 
    }
    
    WorkThread::~WorkThread()
    { 
    }
    
    void WorkThread::run()
    { 
        while (1)
        { 
            for (int n = 0; n < 10; n++)
            { 
                emit currentValue_signal(n);
                msleep(1000);
            }
    
            msleep(1000);
        }
    }

mainwindow.ui  
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