Show a save dialog when the save button is clicked in Printer

Printer.qml

@@ -1,9 +1,29 @@
 import QtQuick 2.1
 import QtQuick.Controls 1.1
 import QtQuick.Layouts 1.1
+import QtQuick.Dialogs 1.1
 
 import UM 1.0 as UM
 
 UM.DefaultWindow {
     title: "Cura"
+
+    function saveClicked() {
+        saveDialog.open();
+    }
+
+    FileDialog {
+        id: saveDialog
+
+        title: "Choose Filename"
+
+        modality: Qt.NonModal;
+
+        selectExisting: false;
+
+        onAccepted:
+        {
+            Printer.saveGCode(fileUrl)
+        }
+    }
 }