iOS基础之懒加载

#import "RootViewController.h"

@interface RootViewController ()
@property(nonatomic,retain)UILabel *label;
@property (nonatomic,retain)UITextField *textField;
@end

@implementation RootViewController
//懒加载
- (UILabel *)label{
    if (_label == nil) {
        _label = [[UILabel alloc]initWithFrame:CGRectMake(200, 100, 100, 20)];
        
    }return _label;
}
- (UITextField *)textField{
    _textField = [[UITextField alloc]initWithFrame:CGRectMake(100, 200, 200, 40)];
    _textField.borderStyle = UITextBorderStyleRoundedRect;
    return _textField;
}
- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.