How to add custom dropdown attribute for category in Magento 2

Question

Now, I've got empty dropdown.

Here is my code (InstallData.php):

public function install(ModuleDataSetupInterface $setup, ModuleContextInterface $context)
{
    $setup->startSetup();

    $eavSetup = $this->eavSetupFactory->create(['setup' => $setup]);

    $eavSetup->addAttribute(
        \Magento\Catalog\Model\Category::ENTITY,
        'width',
        [
            'type' => 'int',
            'label' => 'Width',
            'input' => 'select',
            'source' => 'Magento\Catalog\Model\Category\Attribute\Source\Page',
            'required' => false,
            'sort_order' => 4,
            'global' => \Magento\Eav\Model\Entity\Attribute\ScopedAttributeInterface::SCOPE_STORE,
            'is_html_allowed_on_front' => true,
            'group' => 'General Information',
        ]
    );

    $setup->endSetup();
}

And category_form.xml:

<?xml version="1.0"?>
<form xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
    <fieldset name="display_settings">
        <field name="width">
            <argument name="data" xsi:type="array">
                <item name="config" xsi:type="array">
                    <item name="formElement" xsi:type="string">select</item>
                    <item name="label" xsi:type="string" translate="true">Width</item>
                    <item name="options" xsi:type="array">
                        <item name="33" xsi:type="string">33</item>
                        <item name="50" xsi:type="string">50</item>
                    </item>
                    <item name="default" xsi:type="number">50</item>
                </item>
            </argument>
        </field>
    </fieldset>
</form>

Answer 1

Add following line

<item name="options" xsi:type="object">Magento\Catalog\Model\Category\Attribute\Source\Page</item>

So your xml looks like

<?xml version="1.0"?>
<form xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
    <fieldset name="display_settings">
        <field name="width">
            <argument name="data" xsi:type="array">
                <item name="options" xsi:type="object">Magento\Catalog\Model\Category\Attribute\Source\Page</item>
                <item name="config" xsi:type="array">
                    <item name="formElement" xsi:type="string">select</item>
                    <item name="label" xsi:type="string" translate="true">Width</item>
                    <item name="options" xsi:type="array">
                        <item name="33" xsi:type="string">33</item>
                        <item name="50" xsi:type="string">50</item>
                    </item>
                    <item name="default" xsi:type="number">50</item>
                </item>
            </argument>
        </field>
    </fieldset>
</form>

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