How exactly do you overlay an icon? Like a shortcut icon on Windows?
For example, Dropbox overlayed the icons on the files and folders with a tick sign, indicating that they are in sync with the Dropbox servers.
Windows – How to overlay an icon like the tick sync in Dropbox
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Related Solutions
To exclude FILES, not folders, from Dropbox, there is a trick you can do:
Move the file somewhere else
Create a folder with the same name in place of the file
Go to Dropbox selective sync options and ignore the folder, this will also delete it
Move the file back in place
Example
Enjoy your ignored file!
I went through and enabled/disabled each Dropbox Shell Icon Overlays and found the following results below on Windows 7 x64 and Dropbox 2.10.30.
The 8 icon overlays are as follows:
| Icon Overlay | Color (Icon) | Status | | ------------ | ------------ | ----------------------------------------- | | DropboxExt1 | Green | Synced! | | DropboxExt2 | Blue | Sync in progress | | DropboxExt3 | Green (lock) | Synced! (locked file) | | DropboxExt4 | Blue (lock) | Sync in progress (locked file) | | DropboxExt5 | Red | Sync not happening | | DropboxExt6 | Red (lock) | Sync not happening (locked file) | | DropboxExt7 | Gray | A file/folder isn't syncing | | DropboxExt8 | Gray (lock) | A file/folder isn't syncing (locked file) |
There are not separate overlays for files and folders. Disabling one of the overlays above will affect both. The 4 primary status icons described in this Dropbox help doc are 1, 2, 5, and 7. Overlays 3, 4, 6 and 8 are duplicates of the primary 4, but for locked files. (Thanks BeingInquisitive)
NirSoft's ShellExView is a handy tool to enable/disable Shell Icon Overlays without needing to mess around in the registry. Windows will apply the first 15 Enabled overlays.
If you prefer the manual approach, you can still rename or delete the entries under
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\ShellIconOverlayIdentifiers
Note: For either approach you have to kill/restart the explorer.exe process(es) for the changes to take effect.
Best Answer
For Microsoft Windows, MSDN describes the process of doing this here.
I found that part of the implementation is in the registry, but it takes much more than just creating registry keys and values to have your own similar overlay implementation. Dropbox may be actively determining what overlay icons to display while it is continually running in the background, using techniques similar to the Code Project linked by Paul (at least in Windows version of Dropbox).
If you're interested in removing the green check-marks (you only want other status icons like blue sync), you can find solutions for doing it in Windows, Mac and Linux here. It is from here that I partly found out how Dropbox is implementing the overlays.