In a Windows 8 Metro style app, what is the best practice for asking the user for a name and password, and then allowing the user to change these credientials at a later point in the app lifecycle?
1. Should I create a Settings Popup with username and password as input fields, then on app launch, check if the app don't have a valid username/password, and slide out the settings panel and wait for the user to enter a username and
password?
--or--
2. Create an single page within my app, with the username and password input fields, and a login button?
--or --
3. Rather than a full page within my app, just pop a dialog with username and password input fields and a login button?
Seems like with choice #1, the setting popup is more natural (in case the user needs to change his/her credientials), but Setting properties are to be set automatically (no need to click a button), what should trigger when should when
the app attempts to actually login the user? Assuming login should be attempted when the user clicks away from the setting popup -- what happens if the user logins in with the wrong password, or the server is down, where
should the error message be displayed, -- maybe as a dialog message
#2 or #3, should like a better option if one considered the error cases (wrong credientials, or server is down), but then where do we store the username and password so that the user can login with a different credientials at a later date?
Maybe a hybrid solution, #2, and then on the Settings Popup, display the username as and add a "SignOut" button like SkyDrive does? But should buttons be used on the Settings Popup?
Any advice, good examples, etc. is appreciated.
Tom
