Question

我在Qt / C ++中开发了一个应用程序，它是一个类似的文件浏览器。目前，在删除某些文件或复制某些文件时，我有一个管理整个应用程序和副本的线程，另一个刚刚创建的线程用于显示带有“取消”按钮的进度条。这是非常基本的，但是当我浏览Android设备文件系统时，对删除副本的任何访问都会冻结UI，并且应用程序线程会完成访问。这不是问题，因为我不希望用户在复制或删除时使用UI。

我的问题主要是线程的实时问题。当我使用Qt创建器作为IDE和调试时，我没有任何问题删除工作，并且进度条也显示没有任何问题。当我刚从Qt Creator中使用该应用程序时，该应用程序在尝试显示对话框时经常崩溃。

我非常确定它与线程的链接。当使用调试器和Qt创建器时，整个应用程序会减慢跟踪，调试......

以下是我要求删除时TreeView.cpp的代码：

DialogProgressIndicator *DeleteProgress = new DialogProgressIndicator;
        DeleteProgress->moveToThread(&ProgressThread);
        connect(&ProgressThread, &QThread::finished, DeleteProgress, &QObject::deleteLater);
        connect(this, &PulsTreeWidget::DisplayProgress, DeleteProgress, &DialogProgressIndicator::ShowDlg);
        connect(this, &PulsTreeWidget::UpdateProgress, DeleteProgress, &DialogProgressIndicator::UpdateIndicator);
        connect(this, &PulsTreeWidget::CloseProgress, DeleteProgress, &DialogProgressIndicator::CloseDlg);
        connect(DeleteProgress,&DialogProgressIndicator::CancelAction, this, &PulsTreeWidget::CatchActionCancel);
        ProgressThread.start();
        DisplayProgress();

删除完成后，我按照以下方法关闭所有内容：

CloseProgress();
            ProgressThread.quit();
            disconnect(&ProgressThread, &QThread::finished, FileTransferProgress, &QObject::deleteLater);
            disconnect(this, &PulsTreeWidget::DisplayProgress, FileTransferProgress, &DialogProgressIndicator::ShowDlg);
            disconnect(this, &PulsTreeWidget::UpdateProgress, FileTransferProgress, &DialogProgressIndicator::UpdateIndicator);
            disconnect(this, &PulsTreeWidget::CloseProgress, FileTransferProgress, &DialogProgressIndicator::CloseDlg);
            disconnect(FileTransferProgress,&DialogProgressIndicator::CancelAction, this, &PulsTreeWidget::CatchActionCancel);

类PulsTreeWidget定义如下：

class PulsTreeWidget : public QTreeWidget
{
    Q_OBJECT
    QThread ProgressThread;

public:
    PulsTreeWidget(PulsDeviceMngr& device, PulsMainUI& parent);
    ~PulsTreeWidget();

signals:
    void DisplayProgress();
    void CloseProgress();
    void UpdateProgress(int);

进度条由班级

管理

DialogProgressIndicator.cpp

#include <QApplication>

#include "dialogprogressindicator.h"
#include "ui_dialogprogressindicator.h"

DialogProgressIndicator::DialogProgressIndicator(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::DialogProgressIndicator)
{
    ui->setupUi(this);
    ui->progressBar->setRange(0,100);
    ui->progressBar->setValue(1);

    connect(ui->Cancel, SIGNAL(clicked()), this, SLOT(onClickCancel()));
}

void DialogProgressIndicator::ShowDlg() {
    ui->progressBar->show();
}

void DialogProgressIndicator::CloseDlg() {
    ui->progressBar->close();
}

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

void DialogProgressIndicator::UpdateIndicator(int value) {
    ui->progressBar->setValue(value);
    QApplication::processEvents();
}

void DialogProgressIndicator::onClickCancel() {
    emit CancelAction();
    disconnect(ui->Cancel, SIGNAL(clicked()), this, SLOT(onClickCancel()));
}

我遵循了Qt指南，但在执行＆＃34; DisplayProgress＆＃34;

时仍然崩溃

有什么想法吗？在我执行

的另一个帖子中，它真的崩溃了

void DialogProgressIndicator::ShowDlg() {
    ui->progressBar->show();
}

我添加了崩溃日志：

Application Specific Information:
abort() called

Thread 0:: Dispatch queue: com.apple.main-thread
0   com.apple.AppKit                0x00007fff89e6561f -[NSView(NSInternal) _allocAuxiliary:] + 833
1   com.apple.AppKit                0x00007fff89e67a59 -[NSView _commonAwake] + 36
2   com.apple.AppKit                0x00007fff89e6c841 -[NSView initWithFrame:] + 457
3   libqcocoa.dylib                 0x0000000103c2078f 0x103c0c000 + 83855
4   libqcocoa.dylib                 0x0000000103c20a1d 0x103c0c000 + 84509
5   libqcocoa.dylib                 0x0000000103c18f36 0x103c0c000 + 53046
6   libqcocoa.dylib                 0x0000000103c14b72 0x103c0c000 + 35698
7   QtGui                           0x0000000100f77603 QWindow::create() + 51
8   QtWidgets                       0x0000000101509e13 QWidgetPrivate::create_sys(unsigned long long, bool, bool) + 1107
9   QtWidgets                       0x00000001014df86c QWidget::create(unsigned long long, bool, bool) + 444
10  QtWidgets                       0x00000001014eeebd QWidget::setVisible(bool) + 237
11  QtWidgets                       0x000000010169679d QDialog::setVisible(bool) + 205
12  com.yourcompany.puls_connect    0x0000000100022305 DialogProgressIndicator::ShowDlg() + 21
13  com.yourcompany.puls_connect    0x000000010001a51e void QtPrivate::FunctionPointer<void (DialogProgressIndicator::*)()>::call<void, void>(void (DialogProgressIndicator::*)(), DialogProgressIndicator*, void**) + 142
14  com.yourcompany.puls_connect    0x000000010001a3fa QtPrivate::QSlotObject<void (DialogProgressIndicator::*)(), void, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) + 202
15  QtCore                          0x0000000100bfdda2 QMetaObject::activate(QObject*, int, int, void**) + 1874
16  com.yourcompany.puls_connect    0x00000001000242db PulsTreeWidget::DisplayProgress() + 43

Answer 1

请记住，您只能在主线程中使用GUI类。用于并行任务 QFutureWatcher：

WaitDialog waitDlg(this);
connect(this, SIGNAL(progress(int)), &waitDlg, SLOT(setProgress(int)));
QFutureWatcher<void> watcher;
connect(&watcher, SIGNAL(finished()), &waitDlg, SLOT(close()));
connect(&watcher, SIGNAL(canceled()), &waitDlg, SLOT(close()));
QFuture<void> future = QtConcurrent::run([] () {/*do parallel task here*/});
watcher.setFuture(future);
waitDlg.exec();

显示QDialog框时出现QT Thread问题

1 个答案: