Here’s a little snippet I wrote up the other day to support a Go Home feature for the app I’ve been helping with.  It sets the FLAG_ACTIVITY_CLEAR_TOP flag on the Intent along with the HomeActivity.  This flag, according to the Android docs, launches a new instance of the activity if it isn’t currently running, and closes all the activities on top of it.  So if there are any activities on top of HomeActivity they are cleared and HomeActivity is displayed to the user.  I also added a check to determine if the supplied Context is already the HomeActivity, and if so, ignore the call.

public static void goHome( Context ctx )
{
    if ( ! ( ctx instanceof HomeActivity ) )
    {
        Intent intent = new Intent( ctx, HomeActivity.class );
        intent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP );
        ctx.startActivity( intent );
    }
}

I’ve been prototyping some code using the location api and not only have I learned some new things about this but also worked in the layout ‘include’ tag to minimize the amount of redundency in the layout file, and the Android Java code.  Include allows you to include one layout file in another, there’s an article about it on the Android dev site.  One minor speed bump I ran into was that I didn’t see an immediate way to access the resuseable portion of the layout file via a findById call.  After a little hacking around, the answer was pretty easy.

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