I'm getting following issue when I'm click associated products.
main.INFO: Cache file with merged layout: LAYOUT_adminhtml_STORE1_321f776dd692abd332ec2bb61e502b692 and handles default, attachments_attachments_attachment_products: Please correct the XML data and try again. complex type 'handleType', attribute 'base': The QName value 'layoutType' does not resolve to a(n) simple type definition.
Line: 47
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[2016-07-15 13:35:01] main.INFO: Cache file with merged layout: LAYOUT_adminhtml_STORE1_3cf9ab1b1723bedc1dcd665a812b00335 and handles admin-1column: Please correct the XML data and try again. complex type 'handleType', attribute 'base': The QName value 'layoutType' does not resolve to a(n) simple type definition.
Line: 47
[] []
<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<body>
<block class="Magento\Framework\View\Element\Text\ListText" name="root">
<block class="Web4pro\Attachments\Block\Adminhtml\Attachment\Edit\Tab\Product" name="attachment.edit.tab.product"/>
<block class="Magento\Backend\Block\Widget\Grid\Serializer" name="product_grid_serializer">
<reference name="product_grid_serializer">
<action method="initSerializerBlock">
<arguments>
<argument xsi:type="string" name="grid_block_name">attachment.edit.tab.product</argument>
<argument xsi:type="string" name="data_callback">getSelectedProducts</argument>
<argument xsi:type="string" name="hidden_input_name">products</argument>
<argument xsi:type="string" name="reload_param_name">attachment_products</argument>
</arguments>
</action>
<action method="addColumnInputName">
<arguments>
<argument xsi:type="string" name="input_name">position</argument>
</arguments>
</action>
</reference>
</block>
</block>
</body>
</page>
Please find code below url. https://github.com/sivajik34/Magento2-Product-Attachments