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David Iman
David Iman
1,154 Points

Activity_main.xml error

A few days ago I was working on the Crystal Ball Project and everything was going well..... until today. I tried loading up the project like normal, however, I am now receiving a large error code for my Activity_main window.

It says Cannot create extension will hundreds of error code lines. Here is a small portion of this string of errors.

org.eclipse.core.runtime.CoreException: Cannot create extension
    at org.eclipse.ui.internal.WorkbenchPlugin.createExtension(WorkbenchPlugin.java:296)
    at org.eclipse.ui.internal.registry.EditorDescriptor.createEditor(EditorDescriptor.java:235)
    at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:318)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.createPart(CompatibilityPart.java:266)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityEditor.createPart(CompatibilityEditor.java:61)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.create(CompatibilityPart.java:304)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)

If you need any more information please ask. Help so I can continue.

1 Answer

Ben Jakuben
Ben Jakuben
Treehouse Teacher

This may be a problem with Eclipse itself where you need to update Eclipse and the Android tools. Check the 2:54 mark of this video for a walkthrough of how to update everything. If you get it all up to date and still have this problem, please paste more error messages in here and we'll go from there.

David Iman
David Iman
1,154 Points

Thank you Ben for the reply... However, I have stopped that project and started fresh and so far I am doing just fine. I believe the project had become corrupted some how. I still have the project and will tamper with it some more just to see if I can figure it out.