关于在IOS开发中数据懒加载相关

- (NSMutableArray *)messageArray{
if (_messageArray == nil) {

NSString *path = [[NSBundle mainBundle] pathForResource:@"messages.plist" ofType:nil];
NSArray *dictArr = [NSArray arrayWithContentsOfFile:path];
NSMutableArray *messageFrameArr = [NSMutableArray array];

for (NSDictionary *dict in dictArr) {

WFMessages *message = [WFMessages messagesWithDict:dict];

[messageFrameArr addObject:message];

}

_messageArray = messageFrameArr;

}

return _messageArray;
}