Undo and Redo command

Undo.h

@@ -0,0 +1,21 @@
+#ifndef UNDO_H
+#define UNDO_H
+
+#include <QUndoCommand>
+#include <QLineEdit>
+
+class LineEditCommand : public QUndoCommand {
+public:
+    LineEditCommand(QLineEdit* edit, const QString& oldText, const QString& newText)
+        : m_edit(edit), m_oldText(oldText), m_newText(newText) {}
+
+    void undo() override { m_edit->setText(m_oldText); }
+    void redo() override { m_edit->setText(m_newText); }
+
+private:
+    QLineEdit* m_edit;
+    QString m_oldText;
+    QString m_newText;
+};
+
+#endif // UNDO_H

mainwindow.cpp

@@ -1,15 +1,49 @@
 #include "mainwindow.h"
 #include "ui_mainwindow.h"
 #include "path.h"
-
+#include "Undo.h"
 #include <QFileDialog>
 #include <QMessageBox>
+#include <QLineEdit>
+#include <QTimer>
 
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent)
     , ui(new Ui::MainWindow)
+    , undoStack(new QUndoStack(this))
 {
     ui->setupUi(this);
+
+
+    connect(ui->titleEdit, &QLineEdit::editingFinished, this, [this]() {
+        static QString previousText;
+        QString currentText = ui->titleEdit->text();
+        if(previousText != currentText) {
+            undoStack->push(new LineEditCommand(ui->titleEdit, previousText, currentText));
+            previousText = currentText;
+        }
+    });
+
+    connect(ui->locEdit, &QLineEdit::editingFinished, this, [this]() {
+        static QString previousText;
+        QString currentText = ui->locEdit->text();
+        if(previousText != currentText) {
+            undoStack->push(new LineEditCommand(ui->locEdit, previousText, currentText));
+            previousText = currentText;
+        }
+    });
+
+    connect(ui->imagePath, &QLineEdit::editingFinished, this, [this]() {
+        static QString previousText;
+        QString currentText = ui->imagePath->text();
+        if(previousText != currentText) {
+            undoStack->push(new LineEditCommand(ui->imagePath, previousText, currentText));
+            previousText = currentText;
+        }
+    });
+
+    connect(ui->actionEditUndo, &QAction::triggered, undoStack, &QUndoStack::undo);
+    connect(ui->actionEditRedo, &QAction::triggered, undoStack, &QUndoStack::redo);
 }
 
 MainWindow::~MainWindow()
@@ -136,4 +170,3 @@ void MainWindow::on_actionopenFile_triggered()
 {
     this->loadPath();
 }
-

mainwindow.h

@@ -2,7 +2,7 @@
 #define MAINWINDOW_H
 
 #include <QMainWindow>
-
+#include <QUndoStack>
 #include "path.h"
 
 QT_BEGIN_NAMESPACE
@@ -35,6 +35,7 @@ private slots:
 
     void on_actionopenFile_triggered();
 
+
 private:
     Ui::MainWindow *ui;
     QString currentFile;
@@ -42,5 +43,6 @@ private:
     QList<Path*> path;
     Path* currentPath;
     void loadImage(QString fileName);
+    QUndoStack *undoStack;
 };
 #endif // MAINWINDOW_H

sae201.pro

@@ -15,6 +15,7 @@ SOURCES += \
     path.cpp \
 
 HEADERS += \
+    Undo.h \
     mainwindow.h \
     step.h \
     path.h \