1、环境设置，头文件

该示例使用C++14实现，因此在QT项目pro文件中修改配置

使用智能指针实现，需要的头文件为：

#include <memory>

2、.h文件

2.1、主界面.h文件

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QStackedLayout>
#include "dialogq.h"
#include "dialogw.h"
#include <memory>
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();

    void on_pushButton_2_clicked();

private:
    Ui::MainWindow *ui;
    QStackedLayout * layout;
    std::unique_ptr<Dialogq> dialog11;
    std::unique_ptr<Dialogw> dialog22;
};

#endif // MAINWINDOW_H

2.2、对话界面1.h文件

#ifndef DIALOGQ_H
#define DIALOGQ_H

#include <QWidget>

namespace Ui {
class Dialogq;
}

class Dialogq : public QWidget
{
    Q_OBJECT

public:
    explicit Dialogq(QWidget *parent = nullptr);
    ~Dialogq();

private:
    Ui::Dialogq *ui;
};

#endif // DIALOGQ_H

2.3、对话界面2.h文件

#ifndef DIALOGW_H
#define DIALOGW_H

#include <QWidget>

namespace Ui {
class Dialogw;
}

class Dialogw : public QWidget
{
    Q_OBJECT

public:
    explicit Dialogw(QWidget *parent = nullptr);
    ~Dialogw();

private:
    Ui::Dialogw *ui;
};

#endif // DIALOGW_H

3、.cpp文件

3.1、对话界面1.cpp

#include "dialogq.h"
#include "ui_dialogq.h"

Dialogq::Dialogq(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Dialogq)
{
    ui->setupUi(this);
}

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

3.2、对话界面2.cpp

#include "dialogw.h"
#include "ui_dialogw.h"

Dialogw::Dialogw(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Dialogw)
{
    ui->setupUi(this);
}

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

3.3、主界面.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QStackedLayout>
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    this->dialog11 =std::make_unique<Dialogq>();
    this->dialog22 =std::make_unique<Dialogw>();

    this->layout =new QStackedLayout(ui->frame);

    this->layout->addWidget(dialog11.get());
    this->layout->addWidget(dialog22.get());
}

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

void MainWindow::on_pushButton_clicked()
{
    this->layout->setCurrentWidget(dialog11.get());
}

void MainWindow::on_pushButton_2_clicked()
{
    this->layout->setCurrentWidget(dialog22.get());
}

3.4、main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}