VSIX/VSPackage: Solution Control Explorer context menu - visual-studio-2013

Question

I am having a lot of issues trying to understand how to get a submenu working in VisualStudio 2013's Solution Control Explorer, when creating a VSPackage project. I am able to add buttons, and that is great. However, I want to create the submenus such as the existing "Find" and "Advanced":
The code below is getting the two buttons in the menu list (as seen in the image/link above), but it does not show the submenu. I have tried to add buttons to the submenu, but it still does not show.
<Commands package="guidFirstPackagePkg">
<Menus>
<Menu guid="guidVSPackage3CmdSet" id="SubMenu" priority="0x0100" type="Menu">
<Parent guid="guidSourceControlExplorerMenuGroup" id="SourceControlExplorerMenuGroupId"/>
<Strings>
<ButtonText>Sub Menu</ButtonText>
<CommandName>Sub Menu</CommandName>
</Strings>
</Menu>
</Menus>
<!--Buttons section. -->
<Buttons>
<Button guid="guidVSPackage2CmdSet" id="cmdIdImport" priority="0x0100" type="Button">
<Parent guid="guidSourceControlExplorerMenuGroup" id="SourceControlExplorerMenuGroupId" />
<Strings>
<ButtonText>Import</ButtonText>
</Strings>
</Button>
<Button guid="guidVSPackage2CmdSet" id="cmdIdExport" priority="0x0100" type="Button">
<Parent guid="guidSourceControlExplorerMenuGroup" id="SourceControlExplorerMenuGroupId" />
<Strings>
<ButtonText>Export</ButtonText>
</Strings>
</Button>
</Buttons>
</Commands>
<Symbols>
<!-- This is the package guid. -->
<GuidSymbol name="guidFirstPackagePkg" value="{fd27b3da-39c0-486a-9900-652cb81b0744}" />
<GuidSymbol name="guidSourceControlExplorerMenuGroup" value="{ffe1131c-8ea1-4d05-9728-34ad4611bda9}">
<IDSymbol name="SourceControlExplorerMenuGroupId" value="0x1111" />
</GuidSymbol>
<GuidSymbol name="guidVSPackage2CmdSet" value="{1d975044-0a78-4e91-a6c2-2e841f4280e4}">
<IDSymbol name="cmdIdImport" value="0x0100" />
<IDSymbol name="cmdIdExport" value="0x0110" />
</GuidSymbol>
<GuidSymbol name="guidVSPackage3CmdSet" value="{C860DEF0-0A00-44BE-A8D9-393BACE1A44A}">
<IDSymbol name="SubMenu" value="0x1001"/>
</GuidSymbol>
</Symbols>
Any ideas of what I am doing wrong? Wrong linking, can I not use the same "SourceControlExplorerMenuGroupId" for menus, but only buttons?
I know a related post dealt with the addition of a button to the Solution Control Explorer, however, I was unable to replicated this for a Solution Control Explorer submenu:
Creating VSIX package for TFS Source control explorer context menu extension
Another reference I tried, but was not related to Solution Control Explorer:
Why isn't my vspackage's context menu showing

Answer 1

Your <Menus> code is fine.
Create a group with its parent guid and id matching your menu guid and id:
<Groups>
<Group guid="guidVSPackage3CmdSet" id="MyMenuGroup" priority="0x0600">
<Parent guid="guidVSPackage3CmdSet" id="SubMenu" />
</Group>
</Groups>
Then, just have your buttons be children of the group:
<Buttons>
<Button guid="guidVSPackage2CmdSet" id="cmdIdImport" priority="0x0100" type="Button">
<Parent guid="guidVSPackage3CmdSet" id="MyMenuGroup" />
<Strings>
<ButtonText>Import</ButtonText>
</Strings>
</Button>
<Button guid="guidVSPackage2CmdSet" id="cmdIdExport" priority="0x0100" type="Button">
<Parent guid="guidVSPackage3CmdSet" id="MyMenuGroup" />
<Strings>
<ButtonText>Export</ButtonText>
</Strings>
</Button>
</Buttons>