Add cut function

mainwindow.cpp

@@ -199,6 +199,16 @@ void MainWindow::on_actionEditPaste_triggered()
 
 void MainWindow::on_actionEditCut_triggered()
 {
+    QWidget *focused = QApplication::focusWidget();
+    QLineEdit* lineEdit = qobject_cast<QLineEdit*>(focused);
 
+    if(lineEdit) {
+        QString text = lineEdit->text();
+        QString selectedText = lineEdit->selectedText();
+        int pos = lineEdit->selectionStart();
+        text.remove(pos, selectedText.length());
+        Clipboard->setText(selectedText);
+        lineEdit->setText(text);
+    }
 }