How to create an IconList property in the Windows Property System?

Question

Currently, my property handler provides properties that can be displayed in Windows Explorer columns of type String. My goal is to extend the handler by a prope

Answer 1

There is WINDOWSPROPERTYDESCRIPTIONS resource inside propsys.dll. This resource describes all system props. Some of properties have drawcontrol equal to IconList. Example:

<propertyDescription name="System.StorageProviderUIStatus" formatID="{E77E90DF-6271-4F5B-834F-2DD1F245DDA4}" propID="2">
  <searchInfo reIndexPatterns="" processReIndexPatternsImmediately="true" inInvertedIndex="false" isColumn="false">
  </searchInfo>
  <typeInfo type="Blob" isInnate="true" isViewable="true">
  </typeInfo>
  <labelInfo label="@propsys.dll,-42289">
  </labelInfo>
  <displayInfo defaultColumnWidth="10">
    <drawControl control="IconList">
    </drawControl>
  </displayInfo>
</propertyDescription>

ALL of such props have type equal to "Blob". So Blob is answer.

Update

My little investigation.

The only known (by me) handler that shows icons is OneDrive. Screenshot:

I got value of System.StorageProviderUIStatus property of one of OneDrive files. Value dump:

As you see this is not image or icon. This is Property Store Binary File described in [MS-PROPSTORE]. Decoded form:

System.PropList.StatusIcons = prop:System.StorageProviderState;System.StorageProviderCustomStates
System.PropList.StatusIconsDisplayFlag = 3
StorageProviderState = 2
StorageProviderCustomStates = (binary data)

Binary data in embedded Property Store Binary File. Its decoded form:

StorageProviderFullyQualifiedId = OneDrive!S-1-5-21-782054983-1121033576-3753986437-1001!Personal|79D9464945C2A3B2!331 

Everything looks quite hard for simple icon description. And maybe I`am wrong and Blob type is not the only answer.

SOLUTION

Content of propdesc file:

<propertyDescription name="DummyUIState" formatID="{8A560909-320E-4E6A-A6C4-A95C50B77084}" propID="5001">
  <searchInfo columnIndexType="NotIndexed"/>
  <labelInfo label="DummyUIState"/>
  <typeInfo type="Blob" isInnate="true" isViewable="true"/>
  <displayInfo defaultColumnWidth="10">
    <drawControl control="IconList"/>
  </displayInfo>
</propertyDescription>

<propertyDescription name="DummyState" formatID="{8A560909-320E-4E6A-A6C4-A95C50B77084}" propID="5000">
  <searchInfo columnIndexType="NotIndexed"/>
  <labelInfo label="DummyState"/>
  <typeInfo type="UInt32" isInnate="true" isViewable="true"/>
  <displayInfo displayType="Enumerated">
    <enumeratedList>
      <enum name="None" value="0" text="@propsys.dll,-42290"/>
      <enum name="Sparse" value="1" text="@propsys.dll,-42291">
        <image res="%systemroot%\system32\imageres.dll,-1404"/>
      </enum>
      <enum name="InSync" value="2" text="@propsys.dll,-42292">
        <image res="%systemroot%\system32\imageres.dll,-1400"/>
      </enum>
      <enum name="Pinned" value="3" text="@propsys.dll,-42293">
        <image res="%systemroot%\system32\imageres.dll,-1405"/>
      </enum>
      <enum name="PendingUpload" value="4" text="@propsys.dll,-42294">
        <image res="%systemroot%\system32\imageres.dll,-1401"/>
      </enum>
      <enum name="PendingDownload" value="5" text="@propsys.dll,-42303">
        <image res="%systemroot%\system32\imageres.dll,-1401"/>
      </enum>
      <enum name="Transferring" value="6" text="@propsys.dll,-42296">
        <image res="%systemroot%\system32\imageres.dll,-1401"/>
      </enum>
      <enum name="Error" value="7" text="@propsys.dll,-42315">
        <image res="%systemroot%\system32\imageres.dll,-1402"/>
      </enum>
      <enum name="Warning" value="8" text="@propsys.dll,-42316">
        <image res="%systemroot%\system32\imageres.dll,-1403"/>
      </enum>
      <enum name="Excluded" value="9" text="@propsys.dll,-42319"/>
      <enum name="Pending" value="10" text="@propsys.dll,-42324">
        <image res="%systemroot%\system32\imageres.dll,-1401"/>
      </enum>
    </enumeratedList>
  </displayInfo>
</propertyDescription>

When shell request DummyUIState you must create blob with Property Store Binary File. Property Store Binary File must contain the following data:

1. Key System.PropList.StatusIcons, value with type VT_LPWSTR equal to prop:DummyState
2. Key System.PropList.StatusIconsDisplayFlag, value with type VT_UI4 equal to 2 (2 - icon only, 1 - icon + text)
3. Key DummyState, value type VT_UI4. This value defines the icon.

That's all. Tested on Windows 10. Screenshot: