<?xml version="1.0" encoding="UTF-8"?>
<fields>
<fieldset name="grid_editor" label="Grid Settings">
<field name="auto_generate_thumb"
type="boolean"
default="true"
label="Auto Generate Thumbnail"
description="Choose if auto generate thumb on save">
</field>
<field name="custom_preview_image"
type="image"
default=""
label="Choose Thumbnail"
description="Choose the thumbnail for the layout">
</field>
<field type="control" parent="auto_generate_thumb" child="custom_preview_image" ctype="show" value="false" />
</fieldset>
</fields>