iOS——UIActivityIndicatorView(小菊花)的使用

iOS UIActivityIndicatorView用法（小菊花旋转）

UIActivityIndicatorView初始化方式

• -(instancetype)initWithActivityIndicatorStyle:(UIActivityIndicatorViewStyle)style
• -(instancetype)initWithFrame:(CGRect)frame

其中的第一个初始化方法参数style是个枚举类型。
typedef NS_ENUM(NSInteger, UIActivityIndicatorViewStyle) {
UIActivityIndicatorViewStyleWhiteLarge,
UIActivityIndicatorViewStyleWhite,
UIActivityIndicatorViewStyleGray,
};

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代码示例

这是我在Main.storyboard拖拽的两个按钮，是为了控制开始旋转和停止旋转，也可以自己手写代码呦

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#import "ViewController.h"

@interface ViewController ()
- (IBAction)startAction:(UIButton *)sender;
- (IBAction)stopAction:(UIButton *)sender;
@property (strong, nonatomic) UIActivityIndicatorView *activityIndicator ;
@end

@implementation ViewController

- (void)viewDidLoad {
     [super viewDidLoad];

//    self.activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(100, 100, 60, 60)];
    self.activityIndicator = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:(UIActivityIndicatorViewStyleGray)];
    [self.view addSubview:self.activityIndicator];
     //属性值是一个枚举变量，只有三个值：
    //UIActivityIndicatorViewStyleWhite; 白色圆圈
    //UIActivityIndicatorViewStyleWhiteLarge; 白色圆圈 但是要大些
    //UIActivityIndicatorViewStyleGray; 灰色圆圈
    //    self.activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhiteLarge;
    self.activityIndicator.frame= CGRectMake(100, 100, 100, 100);
    //设置小菊花颜色
    self.activityIndicator.color = [UIColor redColor];
    //设置背景颜色
    self.activityIndicator.backgroundColor = [UIColor cyanColor];
    //刚进入这个界面会显示控件。并且停止旋转也会显示，只是没有在转动而已。
    self.activityIndicator.hidesWhenStopped = NO;
}
- (IBAction)startAction:(UIButton *)sender {
    [self.activityIndicator startAnimating];
}

- (IBAction)stopAction:(UIButton *)sender {
    [self.activityIndicator stopAnimating];
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

这是效果图

• 控件中菊花大小是不变的。只是设置控件的大小。

  
  
  

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