Set a default config value on a ui-component form field

Question

The ui-components format for forms and grids is changing in version 2.2 (dev). (maybe it already did). How can I set a default value for a field.
Before 2.2-dev you could add a field like this in the form.

    <field name="title">
        <argument name="data" xsi:type="array">
            <item name="config" xsi:type="array">
                <item name="dataType" xsi:type="string">text</item>
                <item name="default" xsi:type="string">Some default value.</item>
                <item name="label" xsi:type="string" translate="true">Page Title</item>
                <item name="formElement" xsi:type="string">input</item>
                <item name="source" xsi:type="string">source_here</item>
                <item name="sortOrder" xsi:type="number">20</item>
                <item name="dataScope" xsi:type="string">title</item>
                <item name="validation" xsi:type="array">
                    <item name="required-entry" xsi:type="boolean">true</item>
                </item>
            </item>
        </argument>
    </field>

in 2.2-dev the column looks like this:

    <field name="title" sortOrder="20" formElement="input">
        <argument name="data" xsi:type="array">
            <item name="config" xsi:type="array">
                <item name="source" xsi:type="string">source_here</item>
            </item>
        </argument>
        <settings>
            <validation>
                <rule name="required-entry" xsi:type="boolean">true</rule>
            </validation>
            <dataType>text</dataType>
            <label translate="true">Page Title</label>
            <dataScope>title</dataScope>
        </settings>
    </field>

Notice the default is missing from my second example.
I tried <default>Some default value</default> and the same syntax as for the previous version but the xml does not validate.

Is there a way to do it in the new version or someone overlooked it?

Answer 1

I dig some core files and I see that they have set the default value like this

Source vendor/magento/module-catalog/view/adminhtml/ui_component/category_form.xml

You can try below way May be it will help you:

<field name="title" sortOrder="20" formElement="input">
    <argument name="data" xsi:type="array">
        <item name="config" xsi:type="array">
            <item name="source" xsi:type="string">source_here</item>
            <item name="default" xsi:type="string">Some default value.</item> <!--Default Value-->
        </item>
    </argument>
    <settings>
        <validation>
            <rule name="required-entry" xsi:type="boolean">true</rule>
        </validation>
        <dataType>text</dataType>
        <label translate="true">Page Title</label>
        <dataScope>title</dataScope>
    </settings>
</field>