引言:
一个类似抽奖效果的实现.
效果图
代码:
@interface ViewController ()
@property (weak, nonatomic) IBOutlet UILabel *nameL;
@property (weak, nonatomic) IBOutlet UIButton *button;
@property (nonatomic, strong) NSMutableArray *names;
@property (nonatomic, strong) NSTimer *timer;
@property (nonatomic, assign) BOOL isStart;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.names = [NSMutableArray arrayWithObjects:@"刘一", @"陈二", @"张三", @"李四", @"王五", @"赵六", @"孙七", @"周八", @"吴九", @"郑十", @"刘一1", @"陈二1", @"张三1", @"李四1", @"王五1", @"赵六1", @"孙七1", @"周八1", @"吴九1", @"郑十1", nil];
}
#pragma mark - 抽签按钮
- (IBAction)changeNameClick:(id)sender {
if (self.names.count != 0) {
_isStart = !_isStart;
if (_isStart) {
[self.button setTitle:@"停止抽签" forState:(UIControlStateNormal)];
self.timer = [NSTimer timerWithTimeInterval:0.1 target:self selector:@selector(changeName) userInfo:nil repeats:YES];
[[NSRunLoop currentRunLoop] addTimer:_timer forMode:NSDefaultRunLoopMode];
}else{
[self.button setTitle:@"开始抽签" forState:(UIControlStateNormal)];
[_timer invalidate];
// 如果要 限制每人只能抽取一次 要使用下面的代码
// [self.names removeObjectAtIndex:self.index];
//
// for (NSString *name in self.names) {
// NSLog(@"%@", name);
// }
// NSLog(@"%ld", self.nowNames.count);
}
}else{
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"所有人都已抽到" preferredStyle:(UIAlertControllerStyleAlert)];
UIAlertAction *action = [UIAlertAction actionWithTitle:@"取消" style:(UIAlertActionStyleCancel) handler:nil];
[alert addAction:action];
[self.navigationController pushViewController:alert animated:YES];
}
}
#pragma mark - 随机抽取名字
- (void)changeName {
if (self.names.count != 0) {
NSInteger index = arc4random() % self.names.count;
NSString *name = [self.names objectAtIndex:index];
_nameL.text = name;
}
}
demo下载: RandomDrawDemo
GitHub: https://github.com/LiCheng244/LCUtils
个人博客: http://www.licheng244.com/
