Class

MFMessageComposeViewController

A standard view controller whose interface lets the user compose and send SMS or MMS messages.

Declaration

@interface MFMessageComposeViewController : UINavigationController

Overview

Use an MFMessageComposeViewController object to display the standard message composition interface inside your app. Before presenting the interface, populate the fields with the set of initial recipients and the message you want to send. After presenting the interface, the user can edit your initial values before sending the message.

The composition interface does not guarantee the delivery of your message; it only lets you construct the initial message and present it for user approval. The user may opt to cancel the composition interface, in which case the message and its contents are discarded. If the user opts to send the message, the Messages app takes on the responsibility of sending the message.

Figure 1

The message composition interface

Screenshot of the New Message screen, with a phone number in the To field and a short sentence in the composition text field.

An alternate way to compose SMS messages is to create and open a URL that uses the sms scheme. URLs of that type are directed to the Messages app, which uses your URL to configure the message. For information about the structure of sms URLs, see Apple URL Scheme Reference.

Checking the Availability of the Composition Interface

Before presenting the message compose view controller, always call the the canSendText method to see if the current device is configured to send messages. If the user’s device is not set up to send or receive messages, you can notify the user or simply disable the messaging features in your application. You should not attempt to use this interface if the canSendText method returns NO. If messaging is available, you can also use the canSendAttachments and canSendSubject methods to determine if those specific messaging features are available.

Listing 1

Checking the availability of message services

if (![MFMessageComposeViewController canSendText]) {
   NSLog(@"Message services are not available.");
}

Configuring and Displaying the Composition Interface

After verifying that message services are available, you can create and configure the message composition view controller and then present it like you would any other view controller. Use the methods of this class to specify the message’s recipients and the contents of the message. If attachments or a subject line are supported, you can set values for them as well. Listing 2 shows how to configure the composition interface and present it modally. Always assign a delegate to the messageComposeDelegate property, because the delegate is responsible for dismissing the composition interface later. The delegate object must conform to the MFMessageComposeViewControllerDelegate protocol.

Listing 2

Configuring and presenting the composition interface

MFMessageComposeViewController* composeVC = [[MFMessageComposeViewController alloc] init];
composeVC.messageComposeDelegate = self;
 
// Configure the fields of the interface.
composeVC.recipients = @[@"14085551212"];
composeVC.body = @"Hello from California!";
 
// Present the view controller modally.
[self presentViewController:composeVC animated:YES completion:nil];

The message compose view controller is not dismissed automatically. When the user taps the buttons to send the message or cancel the interface, the message compose view controller calls the messageComposeViewController:didFinishWithResult: method of its delegate. Your implementation of that method must dismiss the view controller explicitly, as shown in Listing 3. You can also use this method to check the result of the operation.

Listing 3

Dismissing the message compose view controller

- (void)messageComposeViewController:(MFMessageComposeViewController *)controller
                 didFinishWithResult:(MessageComposeResult)result {
   // Check the result or perform other tasks.    // Dismiss the message compose view controller.
   [self dismissViewControllerAnimated:YES completion:nil];}

For more information on how to present and dismiss view controllers, see View Controller Programming Guide for iOS.

Detecting Changes to the Availability of Messaging

To be notified of changes to the messaging capabilities of the current device, add an observer to the MFMessageComposeViewControllerTextMessageAvailabilityDidChangeNotification notification. The system delivers that notification to your observer when the status of messaging changes.

Topics

Responding to the View Controller Dismissal

messageComposeDelegate

The delegate to which message-related notifications should be sent.

MFMessageComposeViewControllerDelegate

An interface for responding to user interactions with a message compose view controller.

Determining If Message Composition Is Available

+ canSendText

Returns a Boolean value that indicates whether the current device is capable of sending text messages.

+ canSendAttachments

Indicates whether or not messages can include attachments.

+ canSendSubject

Indicates whether or not messages can include subject lines, according to the user’s configuration in Settings.

+ isSupportedAttachmentUTI:

Indicates whether or not the message can accept a file, with the specified UTI, as an attachment.

Setting the Initial Message Information

recipients

An array of strings that contains the initial recipients of the message.

subject

The initial subject of the message.

body

The initial content of the message.

message

A message object from your iMessage app extension.

Managing Attachments

- disableUserAttachments

Disables the camera/attachment button in the message composition view.

attachments

Returns an array of dictionaries that describe the properties of an attachment.

- addAttachmentURL:withAlternateFilename:

Attaches a specified file to the message.

- addAttachmentData:typeIdentifier:filename:

Attaches arbitrary content to the message.

MFMessageComposeViewControllerAttachmentURL

The URL for the item that is attached to the message.

MFMessageComposeViewControllerAttachmentAlternateFilename

The key for the alternate filename for the file-based item attached to the message.

Handling Notifications

MFMessageComposeViewControllerTextMessageAvailabilityDidChangeNotification

Posted when the value returned by the canSendText class method has changed.

MFMessageComposeViewControllerTextMessageAvailabilityKey

The value of this key is a number object that contains a Boolean value.

Relationships