I’m facing the following error:
res/drawable-hdpi/Twitter.png: Invalid file name: must contain only [a-z0-9_.]
Twitter.png looks like a valid filename to me. None of the other images having names like Facebook.png, RSS.png work.
uppercase is not allowed for resource names..
only lowercase(a-z), 0-9, .(dot) and _ are valid.
Your image names should be