# \[CANCELED\] G4P GUI Builder - cannot reopen a previous generated gui

**URL:** <https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159>\
**Category:** Libraries\
**Created:** [October 29, 2021, 11:53am UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159 "2021-10-29T11:53:15Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![Brun0oO](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@Brun0oO](https://discourse.processing.org/u/Brun0oO)\
**Post date:** [October 29, 2021, 11:53am UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/1 "2021-10-29T11:53:15Z")

</div>

Hi,

I’m having an issue with the G4P GUI Builder tool. I got this error when I try to reopen a previous session with this tool :

```auto
java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: com.apple.laf.AquaTreeUI
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1686)
	at java.base/java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2464)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2358)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:493)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:451)
	at java.desktop/javax.swing.ActionMap.readObject(ActionMap.java:235)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1175)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2325)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream$GetFieldImpl.readFields(ObjectInputStream.java:2643)
	at java.base/java.io.ObjectInputStream.readFields(ObjectInputStream.java:673)
	at java.desktop/javax.swing.JComponent.readObject(JComponent.java:5513)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1175)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2325)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2464)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2358)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:493)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:451)
	at java.desktop/javax.swing.event.EventListenerList.readObject(EventListenerList.java:291)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1175)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2325)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream$GetFieldImpl.readFields(ObjectInputStream.java:2643)
	at java.base/java.io.ObjectInputStream.readFields(ObjectInputStream.java:673)
	at java.desktop/javax.swing.tree.DefaultTreeModel.readObject(DefaultTreeModel.java:693)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1175)
	at java.base/java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2325)
	at java.base/java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2196)
	at java.base/java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1679)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:493)
	at java.base/java.io.ObjectInputStream.readObject(ObjectInputStream.java:451)
	at g4p.tool.gui.treeview.CtrlSketchView.loadModel(Unknown Source)
	at g4p.tool.gui.GuiControl.loadGuiLayout(Unknown Source)
	at g4p.tool.gui.GuiDesigner.<init>(Unknown Source)
	at g4p.tool.G4PTool.run(Unknown Source)
	at processing.app.contrib.ToolContribution.run(ToolContribution.java:124)
	at processing.app.Base.lambda$createToolItem$6(Base.java:861)
	at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1967)
	at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2308)
	at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
	at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
	at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:369)
	at java.desktop/com.apple.laf.ScreenMenuItem.actionPerformed(ScreenMenuItem.java:129)
	at java.desktop/java.awt.MenuItem.processActionEvent(MenuItem.java:690)
	at java.desktop/java.awt.MenuItem.processEvent(MenuItem.java:649)
	at java.desktop/java.awt.MenuComponent.dispatchEventImpl(MenuComponent.java:375)
	at java.desktop/java.awt.MenuComponent.dispatchEvent(MenuComponent.java:363)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.io.NotSerializableException: com.apple.laf.AquaTreeUI
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1185)
	at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1553)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1510)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:349)
	at java.desktop/javax.swing.ArrayTable.writeArrayTable(ArrayTable.java:94)
	at java.desktop/javax.swing.ActionMap.writeObject(ActionMap.java:228)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1145)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1497)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1553)
	at java.base/java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:442)
	at java.desktop/javax.swing.JComponent.writeObject(JComponent.java:5578)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1145)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1497)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1553)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1510)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:349)
	at java.desktop/javax.swing.event.EventListenerList.writeObject(EventListenerList.java:276)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1145)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1497)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1553)
	at java.base/java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:442)
	at java.desktop/javax.swing.tree.DefaultTreeModel.writeObject(DefaultTreeModel.java:682)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at java.base/java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1145)
	at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1497)
	at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1433)
	at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
	at java.base/java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:349)
	at g4p.tool.gui.treeview.CtrlSketchView.saveModel(Unknown Source)
	at g4p.tool.gui.GuiControl.saveGuiLayout(Unknown Source)
	at g4p.tool.gui.GuiDesigner$2.windowDeactivated(Unknown Source)
	at java.desktop/java.awt.AWTEventMulticaster.windowDeactivated(AWTEventMulticaster.java:407)
	at java.desktop/java.awt.AWTEventMulticaster.windowDeactivated(AWTEventMulticaster.java:407)
	at java.desktop/java.awt.Window.processWindowEvent(Window.java:2093)
	at java.desktop/javax.swing.JFrame.processWindowEvent(JFrame.java:298)
	at java.desktop/java.awt.Window.processEvent(Window.java:2037)
	at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5011)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2321)
	at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2772)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4843)
	at java.desktop/java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1950)
	at java.desktop/java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:1059)
	at java.desktop/java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:749)
	at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4892)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2321)
	at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2772)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4843)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
	at java.desktop/java.awt.SentEvent.dispatch(SentEvent.java:70)
	at java.desktop/java.awt.DefaultKeyboardFocusManager$DefaultKeyboardFocusManagerSentEvent.dispatch(DefaultKeyboardFocusManager.java:248)
	at java.desktop/java.awt.DefaultKeyboardFocusManager.sendMessage(DefaultKeyboardFocusManager.java:275)
	at java.desktop/java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:819)
	at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4892)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2321)
	at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2772)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4843)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772)
	... 16 more
java.lang.NullPointerException
	at g4p.tool.gui.GuiControl.makeGUIfromTreeModel(Unknown Source)
	at g4p.tool.gui.GuiControl.loadGuiLayout(Unknown Source)
	at g4p.tool.gui.GuiDesigner.<init>(Unknown Source)
	at g4p.tool.G4PTool.run(Unknown Source)
	at processing.app.contrib.ToolContribution.run(ToolContribution.java:124)
	at processing.app.Base.lambda$createToolItem$6(Base.java:861)
	at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1967)
	at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2308)
	at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
	at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
	at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:369)
	at java.desktop/com.apple.laf.ScreenMenuItem.actionPerformed(ScreenMenuItem.java:129)
	at java.desktop/java.awt.MenuItem.processActionEvent(MenuItem.java:690)
	at java.desktop/java.awt.MenuItem.processEvent(MenuItem.java:649)
	at java.desktop/java.awt.MenuComponent.dispatchEventImpl(MenuComponent.java:375)
	at java.desktop/java.awt.MenuComponent.dispatchEvent(MenuComponent.java:363)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

```

Please note :

- Between the two session (first creation and second opening), it’s the same Processing IDE (v4.0.b2) with the same version of the G4P GUI Builder (v4.4.1) and the same version of the G4P library (v4.3.7) under macOS (Big Sur)…

- The error occurs with a simple gui, for example, just one with a single label…

Apart from this problem the examples in the G4P library work perfectly. I just need this tool to quickly build/iterate my user interface.

Does anyone have an idea to help me out?

Thanks for your help

---

<div class="post-metadata">

**Author:** ![quark](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/quark/32/26_2.png) [@quark](https://discourse.processing.org/u/quark)\
**Post date:** [October 29, 2021, 1:08pm UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/2 "2021-10-29T13:08:34Z")

</div>

Extract from my [website](http://www.lagers.org.uk/g4ptool/index.html)  
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

## Important Notice about GUI Builder versions

When upgrading your version of GUI Builder it is important that you check for backward compatabilty with existing GUI designs.

Consider GUI Builder version 4.2.1 the first digit (4) is the _major version number_ , the second (2) the _minor version number_ and the third and final digit (1) is the _increment_ . GUI Builder cannot edit designs created with earlier versions if either the major or minor version numbers differ. In that situation you would have to manually reinstall the earlier version.  
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

If you look in the sketch folder you will find a folder called `data` inside that you will find a file called `gui.ser.???` where `???` indicates the version of GUI Builder used to create the GUI.

---

<div class="post-metadata">

**Author:** ![Brun0oO](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@Brun0oO](https://discourse.processing.org/u/Brun0oO)\
**Post date:** [October 29, 2021, 2:00pm UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/3 "2021-10-29T14:00:51Z")

</div>

In my case, it’s a “fresh” install without any old version history…  
I just install and use the tool a first time and then reopen it a second time (the Processing IDE has been closed in the meantime).

The generated file `gui.ser.???` in my sketch folder is `gui.ser.4.4`…

---

<div class="post-metadata">

**Author:** ![quark](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/quark/32/26_2.png) [@quark](https://discourse.processing.org/u/quark)\
**Post date:** [October 29, 2021, 2:27pm UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/4 "2021-10-29T14:27:46Z")

</div>

My misunderstanding.  
So I tried it out with

- macOS Mojave 10.14.6
- GUI Builder 4.4.1
- G4P 4.3.7

I followed the following steps

1. Open Processing
2. Opened GUI Builder and added a simple textfield control
3. Saved the sketch
4. Closed Processing
5. Re-opened Processing
6. loaded sketch
7. opened GUI Builder
8. Ran the sketch

and it all worked for me. I also tried it with a label.

Since I can’t reproduce the problem it is difficult to know the cause.

I do suggest that when using GUI Builder you only have the one sketch open.

---

<div class="post-metadata">

**Author:** ![Brun0oO](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@Brun0oO](https://discourse.processing.org/u/Brun0oO)\
**Post date:** [October 29, 2021, 7:25pm UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/5 "2021-10-29T19:25:46Z")

</div>

Ok! it worked for me with Processing 3.5.4 like you (but on macOS Big Sur 11.6).  
If I run the same sequence with Processing 4.0b2, I got the error (at the same time, it’s a beta version).

Thanks for your help, I will continue my tests now with Processing 3.5.4.

---

<div class="post-metadata">

**Author:** ![Brun0oO](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@Brun0oO](https://discourse.processing.org/u/Brun0oO)\
**Post date:** [October 30, 2021, 8:47am UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/6 "2021-10-30T08:47:36Z")

</div>

Vain joy :o(  
I have again the problem which prevents me from reopening the tool even with P3. I don’t know what can corrupt my serialized file, maybe a problem with my computer (I checked my version of Java, nothing to report).  
The trouble is having to work in one shot and that, with a lot of widgets to (re) create. I’m going to have to change my approach and switch to another rapid prototyping tool.  
It’s a pity…

---

<div class="post-metadata">

**Author:** ![quark](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/quark/32/26_2.png) [@quark](https://discourse.processing.org/u/quark)\
**Post date:** [October 30, 2021, 5:37pm UTC](https://discourse.processing.org/t/canceled-g4p-gui-builder-cannot-reopen-a-previous-generated-gui/33159/7 "2021-10-30T17:37:28Z")

</div>

GUI Builder has been available for 10 years and the only time people have reported similar problems is when they tried to edit old sketches that used an earlier version.

Sorry I cannot think what the problem is.

If you want I can have a look at your sketch for you. Send a PM with your email address and I will contact you.