检查iPhone是否可以通过MFMessageComposeViewController发送文本

苹果建议使用 NSClassFromString

MessageComposer示例中的示例:

-(IBAction)showSMSPicker:(id)sender {
//  The MFMessageComposeViewController class is only available in iPhone OS 4.0 or later. 
//  So, we must verify the existence of the above class and log an error message for devices
//      running earlier versions of the iPhone OS. Set feedbackMsg if device doesn't support 
//      MFMessageComposeViewController API.
Class messageClass = (NSClassFromString(@"MFMessageComposeViewController"));

if (messageClass != nil) {          
    // Check whether the current device is configured for sending SMS messages
    if ([messageClass canSendText]) {
        [self displaySMSComposerSheet];
    }
    else {  
        feedbackMsg.hidden = NO;
        feedbackMsg.text = @"Device not configured to send SMS.";

    }
}
else {
    feedbackMsg.hidden = NO;
    feedbackMsg.text = @"Device not configured to send SMS.";
}
}

链接: MessageComposer sample

更新: 我发布的示例代码检查SMS composer的可用性,检查mail composer类似。

试试这个:

#import <MessageUI/MessageUI.h>
#include <dlfcn.h>

if ( dlsym(RTLD_DEFAULT, "MFMailComposeErrorDomain") != NULL ) {
        // MFMessageComposeViewController framework is available
} else {
        // do alternative for no MFMessageComposeViewController
}

您可以使用 UIDevice 班级。

http://developer.apple.com/iphone/library/documentation/uikit/reference/UIDevice_Class/Reference/UIDevice.html

这个 systemName 和 systemVersion