UI篇 -- 自定义view

ui最基础的东西, 自定义视图
1.创建


2. 在自定义视图的.h文件中定义属性
@property (nonatomic, retain) UILabel *label;
@property (nonatomic, retain) UITextField *textField;

1. .m文件中.初始化定义的属性, 如果学的好, 可以把视图frame的赋值放到layoutsubviews中

   • (instancetype)initWithFrame:(CGRect)frame
     {
     self = [super initWithFrame:frame];
     if (self) {
     //再view的初始化方法中, 对所有的子视图进行初始化创建
     self.label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, frame.size.width / 3, frame.size.height)];
     self.label.backgroundColor = [UIColor yellowColor];
     [self addSubview:self.label];
     [self.label release];
     self.textField = [[UITextField alloc] initWithFrame:CGRectMake(frame.size.width / 3, 0, frame.size.width * 2 / 3, frame.size.height)];
     self.textField.backgroundColor = [UIColor blueColor];
     [self addSubview:self.textField];
     [self.textField release];

   }
   return self;
   }

   • (void)dealloc
     {
     [_label release];
     [_textField release];
     [super dealloc];
     }
     在mrc下要加上dealloc, arc下就不用了
2. 接下来就可以使用了 , 在主函数中引用头文件, 就可以使用了
   LTView *view = [[LTView alloc] initWithFrame:CGRectMake(20, 20, 280, 50)];
   view.textField.placeholder = @”asdf”;
   [self.window addSubview:view];
   [view release];