QT 作业 C++ day5

作业

代码

MyQThread.h

class MyThread : public QThread
{
    Q_OBJECT
public:
    MyThread(QObject *parent = nullptr);
protected:
    void run() override;
signals:
    //向ui界面发送的 "复制进度" 的信号
    void copy_process_signal(int index);    
public slots:
    // "复制"信号的槽
    void do_copyfile_slots(QString oldfilename,QString newfilename);
private:
    QString oldfilename;
    QString newfilename;
    bool start_copy_flag=0;
};

#endif // MYTHREAD_H

MyQThread.cpp

MyThread::MyThread(QObject *parent)
    :QThread(parent)
{

}

// "槽"
void MyThread::do_copyfile_slots(QString oldfilename,QString newfilename)
{
    //进入此函数,说明ui界面拖入了文件,需要进行文件复制
    this->oldfilename=oldfilename;  //源文件路径
    this->newfilename=newfilename;  //目标文件路径
    start_copy_flag=1;  //打开标志位
}

void MyThread::run()
{
    qDebug() << "子进程进入run函数";
    while(1)
    {
        if(start_copy_flag)
        {;
            //文件复制(准备阶段)
            QFile old_file(oldfilename);      //拆功能键QFile对象
            QFile new_file(newfilename);
            old_file.open(QIODevice::ReadOnly);    //打开文件
            new_file.open(QIODevice::WriteOnly);
            char data[4096];
            qint64 filesize = old_file.size();     //文件总大小
            qint64 readsize=0;                     //已读大小
            int index_backup=0;                    //任务进度
            
            //文件复制(执行阶段)
            while(1)
            {
                //读取数据
                qint64 real_read__size = old_file.read(data,4096);

                //判断是否读完
                if(real_read__size == 0){break;}        //读取到的字节数为0 说明读取完毕,退出

                //计算"处理进度"
                readsize+=real_read__size;              //已经读取的字节总数
                int index =readsize * 100 / filesize;   //"处理进度"
                
                //告知ui界面 当前“处理进度”
                if(index - index_backup > 1)    //仅当"处理进度"发生变化x时
                {
                    copy_process_signal(index); //才发出信号,让ui重新回执进度
                    qDebug() << "复制进度" << index << " 读取总字节" << readsize << " 文件总大小" << filesize;
                }
                
                //写入数据
                new_file.write(data,real_read__size);
            }
            copy_process_signal(100);         //运行到此说明复制完毕,手动将进度设置为100
            old_file.close();
            new_file.close();
            qDebug() << "复制完毕";
            start_copy_flag = 0;    //关闭标志位
        }
    }
    exec(); // 启动事件循环
}

Widget.h

QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT
public:
    Widget(QWidget *parent = nullptr);
    ~Widget();

    void dropEvent(QDropEvent *event) override;             //释放
    void dragEnterEvent(QDragEnterEvent *event) override;   //进入
private slots:
    void update_copy_process(int index);
signals:
    void copyfile_signal(QString oldfilename,QString newfilename);
private:
    Ui::Widget *ui;
};
#endif // WIDGET_H

Widget.cpp

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->setAcceptDrops(1);    //设置允许拖拽
    MyThread* thread = new MyThread(this);

    // "复制文件"
    QObject::connect(this,&Widget::copyfile_signal,thread,&MyThread::do_copyfile_slots);
    // "任务进度"
    QObject::connect(thread,&MyThread::copy_process_signal,this,&Widget::update_copy_process);

    //滑块相关设置
    QString qss = "QSlider::sub-page{background-color:blue} QSlider::groove:horizontal{background-color:white}";
    ui->slider->setStyleSheet(qss);

    thread->start();
}

Widget::~Widget()
{
    delete ui;
}

//拖入
void Widget::dragEnterEvent(QDragEnterEvent *event)
{
    event->acceptProposedAction();  //接收拖入
}

//释放
void Widget::dropEvent(QDropEvent *event)
{
    //从事件中解析文件名
    const QMimeData* mData = event->mimeData();      //获取其中mimeData
    QList<QUrl> urls_list = mData->urls();           //转为urls_list 文件信息村饭到这个容器中
    QUrl url = urls_list[0];                         //读取容器中第一条数据
    QString oldfilename = url.toLocalFile();         //url 转 "文件名"
    
    //从对话框中获取文件名
    QString newfilename = QFileDialog::getSaveFileName(this,"保存文件","E:\\DAY5","AllFiles (*);;Images (*.png *.xpm *.jpg)");

    //数据部分,交由进程处理
    copyfile_signal(oldfilename,newfilename);
}

//槽函数(子进程任务进度 信号)
void Widget::update_copy_process(int index)
{
    //设置进度条
    ui->slider->setValue(index);
}

效果