diff --git a/day11/switchab/awidget.cpp b/day11/switchab/awidget.cpp
new file mode 100755
index 0000000..03697d7
--- /dev/null
+++ b/day11/switchab/awidget.cpp
@@ -0,0 +1,42 @@
+#include "awidget.h"
+
+aWidget::aWidget(QWidget *parent)
+    : QWidget(parent)
+{
+    // 设置A窗口实例的属性
+    setFixedSize(400,200);
+    setWindowTitle("A界面");
+    move(200,100);
+
+    // 新建B窗口对象
+    b = new bWidget();
+    b->setFixedSize(400,200);
+    b->setWindowTitle("B界面");
+    b->move(800,100);
+
+    // 新建“进入B”按钮，并设置其属性
+    btnToB = new QPushButton("进入B",this);
+    btnToB->resize(60,40);
+
+    // 绑定“进入B”按钮点击信号与“进入B界面并隐藏A界面”的槽函数
+    connect(btnToB,&QPushButton::clicked,this,&aWidget::toBHandle);
+    // 绑定“B界面返回A界面信号”与当前界面的“A界面显示并隐藏B界面”的槽函数
+    connect(b,&bWidget::returnASignal,this,&aWidget::returnAHandle);
+}
+
+void aWidget::toBHandle()
+{
+    this->hide(); // 隐藏A界面
+    b->show(); // 显示B界面
+}
+
+void aWidget::returnAHandle()
+{
+    b->hide(); // 隐藏B界面
+    this->show(); // 显示A界面
+}
+
+aWidget::~aWidget()
+{
+}
+
diff --git a/day11/switchab/awidget.h b/day11/switchab/awidget.h
new file mode 100755
index 0000000..1f84c7b
--- /dev/null
+++ b/day11/switchab/awidget.h
@@ -0,0 +1,32 @@
+#ifndef AWIDGET_H
+#define AWIDGET_H
+
+#include <QWidget>
+#include <QPushButton>
+#include <QDebug>
+#include "bwidget.h"
+
+class aWidget : public QWidget
+{
+    Q_OBJECT
+
+private:
+    bWidget *b;
+
+public slots:
+    void toBHandle();
+    void returnAHandle();
+
+signals:
+    void toBSignal();
+
+private:
+    QPushButton *btnToB;
+
+
+
+public:
+    aWidget(QWidget *parent = nullptr);
+    ~aWidget();
+};
+#endif // AWIDGET_H
diff --git a/day11/switchab/bwidget.cpp b/day11/switchab/bwidget.cpp
new file mode 100755
index 0000000..dbbd881
--- /dev/null
+++ b/day11/switchab/bwidget.cpp
@@ -0,0 +1,16 @@
+#include "bwidget.h"
+
+bWidget::bWidget(QWidget *parent) : QWidget(parent)
+{
+    // 新建“返回A”按钮，并设置其属性
+    btnReturnA = new QPushButton("返回A",this);
+    btnReturnA->resize(60,40);
+
+    // 绑定“返回A”按钮点击事件与“发送返回A界面的信号”的槽函数
+    connect(btnReturnA,&QPushButton::clicked,this,&bWidget::sendReturnASignal);
+}
+
+void bWidget::sendReturnASignal()
+{
+    emit returnASignal(); // 触发“返回A界面”信号
+}
diff --git a/day11/switchab/bwidget.h b/day11/switchab/bwidget.h
new file mode 100755
index 0000000..b1bb71a
--- /dev/null
+++ b/day11/switchab/bwidget.h
@@ -0,0 +1,28 @@
+#ifndef BWIDGET_H
+#define BWIDGET_H
+
+#include <QWidget>
+#include <QPushButton>
+#include <QDebug>
+
+class bWidget : public QWidget
+{
+    Q_OBJECT
+
+private:
+    QPushButton *btnReturnA;
+
+public slots:
+    void sendReturnASignal();
+
+signals:
+    void returnASignal();
+
+public:
+    explicit bWidget(QWidget *parent = nullptr);
+
+signals:
+
+};
+
+#endif // BWIDGET_H
diff --git a/day11/switchab/main.cpp b/day11/switchab/main.cpp
new file mode 100755
index 0000000..320b357
--- /dev/null
+++ b/day11/switchab/main.cpp
@@ -0,0 +1,12 @@
+#include "awidget.h"
+#include "bwidget.h"
+
+#include <QApplication>
+
+int main(int argc, char *argv[])
+{
+    QApplication qa(argc, argv);
+    aWidget a; // 新建一个界面A对象a
+    a.show(); // 程序初始化运行时显示A对象a界面
+    return qa.exec();
+}
diff --git a/day11/switchab/switchab.pro b/day11/switchab/switchab.pro
new file mode 100755
index 0000000..49f3963
--- /dev/null
+++ b/day11/switchab/switchab.pro
@@ -0,0 +1,30 @@
+QT       += core gui
+
+greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
+
+CONFIG += c++11
+
+# The following define makes your compiler emit warnings if you use
+# any Qt feature that has been marked deprecated (the exact warnings
+# depend on your compiler). Please consult the documentation of the
+# deprecated API in order to know how to port your code away from it.
+DEFINES += QT_DEPRECATED_WARNINGS
+
+# You can also make your code fail to compile if it uses deprecated APIs.
+# In order to do so, uncomment the following line.
+# You can also select to disable deprecated APIs only up to a certain version of Qt.
+#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
+
+SOURCES += \
+    bwidget.cpp \
+    main.cpp \
+    awidget.cpp
+
+HEADERS += \
+    awidget.h \
+    bwidget.h
+
+# Default rules for deployment.
+qnx: target.path = /tmp/$${TARGET}/bin
+else: unix:!android: target.path = /opt/$${TARGET}/bin
+!isEmpty(target.path): INSTALLS += target