为iPhone的文本或电子邮件添加进度条（UIProgressView）

Question

Does anyone have tutorials or code snippets to add a Progress Bar for the MFMessageComposeViewController and MFMailComposeViewController? I'm assuming you could add a progress bar as a subview, but not really sure. Thanks.

Answer 1

I would be hesitant about trying to modify those view controllers. The documentation specifically says that you shouldn't try to mess with them in that way, as they are meant to be displayed "as is". In any case, why don't you try adding a UIProgressView to the view controller's view? If not, you could add it directly to the window—generally ill-advised—at the appropriate time and remove it when you're done.

By the way, why are you trying to add a progress view to those view controllers? Those controllers don't provide any sort of state about whether a message was sent successfully or not, only whether or not the user canceled the operation.