urho3d/bin/Data/UI/EditorInspectorWindow.xml

<element type="Window">
    <attribute name="Name" value="AttributeInspectorWindow" />
    <attribute name="Is Movable" value="true" />
    <attribute name="Is Resizable" value="true" />
    <attribute name="Resize Border" value="6 6 6 6" />
    <attribute name="Layout Mode" value="Vertical" />
    <attribute name="Layout Spacing" value="4" />
    <attribute name="Layout Border" value="6 6 6 6" />
    <element>
        <attribute name="Min Size" value="0 16" />
        <attribute name="Max Size" value="2147483647 16" />
        <attribute name="Layout Mode" value="Horizontal" />
        <attribute name="Layout Spacing" value="4" />
        <element type="Text">
            <attribute name="Text" value="Attribute inspector" />
        </element>
        <element type="Button" style="Button">
                <attribute name="Name" value="LockButton" />
                <attribute name="Min Size" value="16 16" />
                <attribute name="Max Size" value="16 16" />
                <attribute name="Layout Mode" value="Horizontal" />
                <element type="BorderImage">
                        <attribute name="Texture" value="Texture2D;Textures/Editor/EditorIcons.png" />
                        <attribute name="Image Rect" value="224 80 238 94" />
                </element>
        </element>
        <element type="Button" style="CloseButton">
            <attribute name="Name" value="CloseButton" />
        </element>
    </element>
    <element style="Panel">
        <attribute name="Name" value="ParentContainer" />
    </element>
</element>