问无法单击带有QPushButton父级的Designer窗体的类Widget中的QT - MainWIndow

EN

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow *w;
    if(argc == 2)
    {
        w = new MainWindow(argv[1]);
    }
    else
    {
        w = new MainWindow();
    }

    w->show();

    return a.exec();
}

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow (parent),
    ui(new Ui::MainWindow),
    todoWidget(nullptr)
{
    ui->setupUi(this);
    todoWidget = new TodoWidget(nullptr, this);
    todoWidget->setEnabled(true);
}

MainWindow::MainWindow(const char *saveFilePath, QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow),
    todoWidget(new TodoWidget(saveFilePath, this))
{
    ui->setupUi(this);
}

MainWindow::~MainWindow()
{
    delete ui;
    delete todoWidget;
}

TodoWidget::TodoWidget(const char *path, QWidget *parent) :
    QWidget (parent),
    t (nullptr),
    ui(new Ui::TodoWidget)
{
    ui->setupUi(this);
    if(!path)
    {
        path = "./tasks/taks";
    }
    open(path);
    makeConnections();
    todoModel = new TaskListModel(t->tasksWithStatus(Task::Status::TODO), this);
    inProgressModel = new TaskListModel(t->tasksWithStatus(Task::Status::IN_PROGRESS), this);
    finishedModel = new TaskListModel(t->tasksWithStatus(Task::Status::FINISHED), this);
//  ui->todoView->setModel(todoModel);
//  ui->inProgressView->setModel(inProgressModel);
//  ui->finishedView->setModel(finishedModel);
}

TodoWidget::~TodoWidget()
{
    delete t;
    delete ui;
}

void TodoWidget::open(const char *path)
{
    if(validateSaveFile(path))
    {
        delete t;
        t = new todo(path, this);
        this->path = path;
    }
}

void TodoWidget::progressTask(unsigned int index)
{
    t->progressTask(index);
}

void TodoWidget::displaySuccess(const QString &msg)
{
    QMessageBox::information(this, "Success", msg);
}

void TodoWidget::displayError(const QString &errMsg)
{
    QMessageBox::critical(this, "Error", errMsg);
}

void TodoWidget::changeProject(const char *path)
{
    open(path);
}

void TodoWidget::addButtonClicked()
{
    AddWindow *addWindow = new AddWindow(this);
    connect(addWindow, &AddWindow::addTask, [this](const QString &args)->void{addTask(args);});
    addWindow->show();
}

bool TodoWidget::validateSaveFile(const QString &path)
{
    /*
     * C:/ and (wordchar 0 or more times/) 0 or more times
     * ./ and (wordchar 0 or more times/) 0 or more times
     * / and (wordchar 0 or more times/) 0 or more times
     * (wordchar 0 or more times/) 0 or more times
     *
     * Note: the parentheses are not present in the regexp
     * Note: wordchar is any character which might be part of a word (alfanum and _ I think)
     */
    QRegularExpression regexp("([a-zA-Z]:/|[.]{0,2}/)?((.*)/)*");
    QRegularExpressionMatch match = regexp.match(path);

    if(!match.hasMatch())
    {
        emit someError("Not a valid file");
        return false;
    }
    else
    {
        QDir sp(match.captured(0));
        if(!sp.exists())
        {
            sp.mkpath(".");
        }
    }
    QFile file(path);
    if(!file.open(QIODevice::Append | QIODevice::Text))
    {
        emit someError(QString("Can't open file") + file.errorString());
        return false;
    }
    return true;
}

void TodoWidget::makeConnections()
{
    connect(t, &todo::taskAdded, this, &TodoWidget::displaySuccess);
    connect(t, &todo::taskNotAdded, this, &TodoWidget::displayError);
    connect(t, &todo::taskMadeProgress, this, &TodoWidget::displaySuccess);
    connect(t, &todo::noProgress, this, &TodoWidget::displayError);
    connect(t, &todo::saved, this, &TodoWidget::displaySuccess);
    connect(t, &todo::notSaved, this, &TodoWidget::displayError);
    connect(this, &TodoWidget::addTask, t, &todo::addTask);
    connect(this, &TodoWidget::someError, this, &TodoWidget::displayError);
    connect(this->ui->addButton, &QPushButton::clicked, this, &TodoWidget::addButtonClicked);
}

void TodoWidget::modelStuff()
{

}