iOS UIActivityIndicatorView用法（小菊花旋轉(zhuǎn)）

UIActivityIndicatorView初始化方式

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

其中的第一個初始化方法參數(shù)style是個枚舉類型。
typedef NS_ENUM(NSInteger, UIActivityIndicatorViewStyle) {
UIActivityIndicatorViewStyleWhiteLarge,
UIActivityIndicatorViewStyleWhite,
UIActivityIndicatorViewStyleGray,
};

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代碼示例

這是我在Main.storyboard拖拽的兩個按鈕，是為了控制開始旋轉(zhuǎn)和停止旋轉(zhuǎn)，也可以自己手寫代碼呦

59C9330B-B51C-408D-BB1F-F8DA448C6595.png

#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];
     //屬性值是一個枚舉變量，只有三個值：
    //UIActivityIndicatorViewStyleWhite; 白色圓圈
    //UIActivityIndicatorViewStyleWhiteLarge; 白色圓圈 但是要大些
    //UIActivityIndicatorViewStyleGray; 灰色圓圈
    //    self.activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhiteLarge;
    self.activityIndicator.frame= CGRectMake(100, 100, 100, 100);
    //設(shè)置小菊花顏色
    self.activityIndicator.color = [UIColor redColor];
    //設(shè)置背景顏色
    self.activityIndicator.backgroundColor = [UIColor cyanColor];
    //剛進(jìn)入這個界面會顯示控件。并且停止旋轉(zhuǎn)也會顯示，只是沒有在轉(zhuǎn)動而已。
    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

這是效果圖

• 控件中菊花大小是不變的。只是設(shè)置控件的大小。

  
  
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