UIButton---按住录音，松开停止_uibutton按住说话

这几天做到录音，要求是 按住录音，松开停止录音完成， 手拖到按钮外时取消录音

先看看UIControlEvent的解释

UIControlEventTouchDown
单点触摸按下事件：用户点触屏幕，或者又有新手指落下的时候。
UIControlEventTouchDownRepeat
多点触摸按下事件，点触计数大于1：用户按下第二、三、或第四根手指的时候。
UIControlEventTouchDragInside
当一次触摸在控件窗口内拖动时。
UIControlEventTouchDragOutside
当一次触摸在控件窗口之外拖动时。
UIControlEventTouchDragEnter
当一次触摸从控件窗口之外拖动到内部时。
UIControlEventTouchDragExit
当一次触摸从控件窗口内部拖动到外部时。
 
UIControlEventTouchUpInside
所有在控件之内触摸抬起事件。
UIControlEventTouchUpOutside
所有在控件之外触摸抬起事件(点触必须开始与控件内部才会发送通知)。
UIControlEventTouchCancel
所有触摸取消事件，即一次触摸因为放上了太多手指而被取消，或者被上锁或者电话呼叫打断。
UIControlEventTouchChanged
当控件的值发生改变时，发送通知。用于滑块、分段控件、以及其他取值的控件。你可以配置滑块控件何时发送通知，在滑块被放下时发送，或者在被拖动时发送。
UIControlEventEditingDidBegin
当文本控件中开始编辑时发送通知。
UIControlEventEditingChanged
当文本控件中的文本被改变时发送通知。
UIControlEventEditingDidEnd
当文本控件中编辑结束时发送通知。
UIControlEventEditingDidOnExit
当文本控件内通过按下回车键（或等价行为）结束编辑时，发送通知。
UIControlEventAlltouchEvents
通知所有触摸事件。
UIControlEventAllEditingEvents
通知所有关于文本编辑的事件。
UIControlEventAllEvents
通知所有事件。

刚开始的时候 我是这么设置的

#import "ViewController.h"
 
@interface ViewController ()
@property (nonatomic, strong) UIButton *recordButton;
@property (nonatomic, strong) UIActivityIndicatorView *indicator;
@end
 
@implementation ViewController
 
- (UIActivityIndicatorView *)indicator
{
    if (!_indicator) {
        _indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
        _indicator.center = _recordButton.center;
        [self.view addSubview:_indicator];
    }
    return _indicator;
}
 
- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
 
    _recordButton = [[UIButton alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
    _recordButton.backgroundColor = [UIColor redColor];
    // 开始
    [_recordButton addTarget:self action:@selector(recordStart:) forControlEvents:UIControlEventTouchDown];
    // 取消
    [_recordButton addTarget:self action:@selector(recordCancel:) forControlEvents: UIControlEventTouchDragExit | UIControlEventTouchUpOutside];
    //完成
    [_recordButton addTarget:self action:@selector(recordFinish:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:_recordButton];
    _recordButton.layer.cornerRadius = 50;
}
 
- (void)recordStart:(UIButton *)button
{
    [self.indicator startAnimating];
    [button setTitle:@"录制中" forState:UIControlStateNormal];
    NSLog(@"UIControlEventTouchDown---recordStart");
}
 
- (void)recordCancel:(UIButton *)button
{
    if (self.indicator.isAnimating) {
        [self.indicator stopAnimating];
    }
    [self.recordButton setTitle:@"重新录制" forState:UIControlStateNormal];
     NSLog(@"UIControlEventTouchDragExit 和 UIControlEventTouchUpOutside---recordCancel");
}
 
- (void)recordFinish:(UIButton *)button
{
    NSLog(@"UIControlEventTouchUpInside---recordFinish");
    [button setTitle:@"完成" forState:UIControlStateNormal];
    [self.indicator stopAnimating];
}

这样会有个问题就是手已经滑到按钮边界外了 还没触发取消的 感觉有点奇怪

后来看了一下相关资料找到解决方法

- (BOOL)continueTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event
{
    // 设置新的边界
    CGFloat boundsExtension = 25.0f;
    CGRect outerBounds = CGRectInset(self.bounds, -1 * boundsExtension, -1 * boundsExtension);
    // 判断触摸位置
    BOOL touchOutside = !CGRectContainsPoint(outerBounds, [touch locationInView:self]);
    if(touchOutside)
    {
        // 判断是UIControlEventTouchDragExit/UIControlEventTouchDragOutside
        BOOL previousTouchInside = CGRectContainsPoint(outerBounds, [touch previousLocationInView:self]);
        if(previousTouchInside)
        {
            [self sendActionsForControlEvents:UIControlEventTouchDragExit];
        }
        else
        {
            [self sendActionsForControlEvents:UIControlEventTouchDragOutside];
        }
    }
    // 如果不是想要修改的control event，返回原操作
    return [super continueTrackingWithTouch:touch withEvent:event];
}

把触发区域缩小了 但是还是有个问题就是touchupinside的识别区域 也是超出按钮的 也就是说调完touupoutside以后（如果你距离按钮区域不远的话）还会再调用touchupinside的方法

增加一个标志来代表已经取消了

- (void)recordStart:(UIButton *)button
{
    _isCancel = NO;
    [self.indicator startAnimating];
    [self.recordButton setTitle:@"录制中" forState:UIControlStateNormal];
}
 
- (void)recordCancel:(UIButton *)button
{
    _isCancel = YES;
    if (self.indicator.isAnimating) {
        [self.indicator stopAnimating];
    }
    [self.recordButton setTitle:@"重新录制" forState:UIControlStateNormal];
}
 
- (void)recordFinish:(UIButton *)button
{
    if (!_isCancel) {
        [self.recordButton setTitle:@"完成" forState:UIControlStateNormal];
        [self.indicator stopAnimating];
    }
}