Question

I’m trying to use the MFMailComposeViewController in an iPhone app I’m building, but I can’t get it to work correctly. I was following the Apple’s sample code MailComposer. As you can see in the sample, the MFMailComposeViewController lets you type in whatever message you want, and in the case of recipients you can either type the email addresses or pick them from your contacts. My implementation is exactly as in the sample, and the MFMailComposeViewController appears and disappears as expected. However, the controller seems to be in read-only mode; i.e., the user can’t change any of the fields. I can change the values of the different fields programmatically before showing the controller, but once it’s visible no modifications can be done to any of the fields. I have checked everything a bunch of times, but I can’t find anything different between my implementation and Apple’s. I’m stumped! Has anyone encountered this issue before? Any suggestions?

Thanks a lot for any help you all can provide!

Answer 1

Found the problem! A parent view controller in my application listens to shake gestures, which requires that view controller listening for shakes becomes the first responder. The parent view controller needs to call

[self resignFirstResponder];

before showing the MFMailComposeViewController. After adding that line, the MFMailComposeViewController worked like a charm.

In general, any view controllers listening for shake gestures should resign first responder before showing any other view controllers. Otherwise, the app will continue to respond to shake gestures even when the corresponding view controller is not visible, which can definitely lead to even worse problems than the MFMailComposeViewController showing up in weird read-only mode.