阅读 58

iOS学习笔记07 运动事件和远程控制

之前我们已经学习了触摸处理和手势识别,其实这两个同属于iOS事件的触摸事件,今天我们来学习下iOS事件的另外两个事件: ###一、运动事件 运动事件,是通过加速器进行触发,和触摸事件一样,继承UIResponder类的对象才能处理运动事件 ######UIResponder处理运动事件的方法:

#pragma mark 运动开始时执行
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event;
#pragma mark 运动结束后执行
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event;
#pragma mark 运动被意外取消时执行
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event;
复制代码

你没有看错,这里说的运动事件,只是摇晃一下手机而已,所以只有运动开始、运动结束、运动取消,无法取得运动过程中的运动速度、运动方向等数据,这些需要另外的框架去实现,我们可以理解这里的运动时间为 “摆动事件” 。 ######监听运动事件前提:

  1. 监听对象必须成为第一响应者,控件需要- (BOOL)canBecomeFirstResponder方法返回YES
  1. 在视图控制器的- (void)viewWillAppear:(BOOL)animated方法中调用运动控件的becomeFirstResponder方法,使控件显示时成为第一响应者
  2. 在视图控制器的- (void)viewDidDisappear:(BOOL)animated方法中调用运动控件的resignFirstResponder方法,使控件不显示时注销控件的第一响应者身份

####实例: ######KCImageView.m

#import "KCImageView.h"
#define kImageCount 3
@implementation KCImageView
- (instancetype)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (self) {
        self.image = [self getImage];
    }
    return self;
}
#pragma mark 设置控件可以成为第一响应者
- (BOOL)canBecomeFirstResponder{
    return YES;
}
#pragma mark 运动开始
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event{
    //这里只处理摇晃事件
    if (motion == UIEventSubtypeMotionShake) {
        self.image = [self getImage];
    }
}
#pragma mark 运动结束
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event{
}
#pragma mark 随机取得图片
- (UIImage *)getImage{
    int index = arc4random() % kImageCount;
    NSString *imageName = [NSString stringWithFormat:@"avatar%i.png",index];
    UIImage *image = [UIImage imageNamed:imageName];
    return image;
}
@end
复制代码

######KCShakeViewController.m

#import "KCShakeViewController.h"
#import "KCImageView.h"
@interface KCShakeViewController (){
    KCImageView *_imageView;
}
@end
@implementation KCShakeViewController
- (void)viewDidLoad {
    [super viewDidLoad];
}
#pragma mark 视图显示时让控件变成第一响应者
- (void)viewDidAppear:(BOOL)animated{
    _imageView = [[KCImageView alloc] initWithFrame:[UIScreen mainScreen].applicationFrame];
    _imageView.userInteractionEnabled = true;
    [self.view addSubview:_imageView];
    [_imageView becomeFirstResponder];
}
#pragma mark 视图不显示时注销控件第一响应者的身份
- (void)viewDidDisappear:(BOOL)animated{
    [_imageView resignFirstResponder];
}
@end
复制代码

运动事件实例效果

###二、远程控制事件 iOS远程控制事件,是通过其他远程设备触发的(比如耳机控制按钮),iOS远程控制事件相关的只有-(void)remoteControlReceivedWithEvent:(UIEvent *)event #####监听远程控制事件的前提:

  1. 启动远程事件接收,调用 [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
  1. UI控件同样要求必须成为第一响应者【使用参考运动事件】 但如果是视图控制器或UIApplication,就没有要求成为第一响应者
  2. 应用程序必须是 当前音频额控制者

######目前iOS7给我们的远程控制权限仅限于音频控制

typedef NS_ENUM(NSInteger, UIEventSubtype) {
    // 不包含任何子事件类型
    UIEventSubtypeNone                              = 0,
    // 摇晃事件(从iOS3.0开始支持此事件)
    UIEventSubtypeMotionShake                       = 1,
    //远程控制子事件类型(从iOS4.0开始支持远程控制事件)
    //播放事件【操作:停止状态下,按耳机线控中间按钮一下】
    UIEventSubtypeRemoteControlPlay                 = 100,
    //暂停事件
    UIEventSubtypeRemoteControlPause                = 101,
    //停止事件
    UIEventSubtypeRemoteControlStop                 = 102,
    //播放或暂停切换【操作:播放或暂停状态下,按耳机线控中间按钮一下】
    UIEventSubtypeRemoteControlTogglePlayPause      = 103,
    //下一曲【操作:按耳机线控中间按钮两下】
    UIEventSubtypeRemoteControlNextTrack            = 104,
    //上一曲【操作:按耳机线控中间按钮三下】
    UIEventSubtypeRemoteControlPreviousTrack        = 105,
    //快退开始【操作:按耳机线控中间按钮三下不要松开】
    UIEventSubtypeRemoteControlBeginSeekingBackward = 106,
    //快退停止【操作:按耳机线控中间按钮三下到了快退的位置松开】
    UIEventSubtypeRemoteControlEndSeekingBackward   = 107,
    //快进开始【操作:按耳机线控中间按钮两下不要松开】
    UIEventSubtypeRemoteControlBeginSeekingForward  = 108,
    //快进停止【操作:按耳机线控中间按钮两下到了快进的位置松开】
    UIEventSubtypeRemoteControlEndSeekingForward    = 109,
};
复制代码

#####实例:

#import "ViewController.h"
@interface ViewController (){
    UIButton *_playButton;
    BOOL _isPlaying;
}
@end
@implementation ViewController      
- (void)viewDidLoad {
    [super viewDidLoad];
    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
    [self initLayout];
}
- (BOOL)canBecomeFirstResponder{
    return NO;
}
- (void)viewDidAppear:(BOOL)animated{
    [super viewDidAppear:animated];
	NSURL *url = [NSURL URLWithString:@"http://stream.jewishmusicstream.com:8000"];
    _player = [[AVPlayer alloc] initWithURL:url];
}
#pragma mark 远程控制事件
- (void)remoteControlReceivedWithEvent:(UIEvent *)event{
    if(event.type == UIEventTypeRemoteControl){
        switch (event.subtype) {
            case UIEventSubtypeRemoteControlPlay:
                [_player play];
                _isPlaying = true;
                break;
            case UIEventSubtypeRemoteControlTogglePlayPause:
                [self btnClick:_playButton];
                break;
            case UIEventSubtypeRemoteControlNextTrack:
                NSLog(@"Next...");
                break;
            case UIEventSubtypeRemoteControlPreviousTrack:
                NSLog(@"Previous...");
                break;
            case UIEventSubtypeRemoteControlBeginSeekingForward:
                NSLog(@"Begin seek forward...");
                break;
            case UIEventSubtypeRemoteControlEndSeekingForward:
                NSLog(@"End seek forward...");
                break;
            case UIEventSubtypeRemoteControlBeginSeekingBackward:
                NSLog(@"Begin seek backward...");
                break;
            case UIEventSubtypeRemoteControlEndSeekingBackward:
                NSLog(@"End seek backward...");
                break;
            default:
                break;
        }
        [self changeUIState];
    }
}
#pragma mark 界面布局
- (void)initLayout{
    //专辑封面
    UIImage *image = [UIImage imageNamed:@"wxl.jpg"];
	CGRect *frame = [UIScreen mainScreen].applicationFrame;
    UIImageView *imageView = [[UIImageView alloc] initWithFrame:frame];
    imageView.image = image;
    imageView.contentMode = UIViewContentModeScaleAspectFill;
    [self.view addSubview:imageView];
    //播放控制面板
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 480, 320, 88)];
    view.backgroundColor = [UIColor lightGrayColor];
    view.alpha = 0.9;
    [self.view addSubview:view];
    //添加播放按钮
    _playButton = [UIButton buttonWithType:UIButtonTypeCustom];
    _playButton.bounds = CGRectMake(0, 0, 50, 50);
	CGFloat playBtnX = view.frame.size.width/2;
	CGFloat playBtnY = view.frame.size.height/2;
    _playButton.center = CGPointMake(playBtnX, playBtnY);
    [self changeUIState];
    [_playButton addTarget:self 
					action:@selector(btnClick:) 
		  forControlEvents:UIControlEventTouchUpInside];
    [view addSubview:_playButton];
}
#pragma mark 界面状态
- (void)changeUIState{
    if(_isPlaying){
		UIImage *pauseImage = [UIImage imageNamed:@"playing_btn_pause_n.png"];
		UIImage *pauseImageH = [UIImage imageNamed:@"playing_btn_pause_h.png"];
        [_playButton setImage:pauseImage forState:UIControlStateNormal];
        [_playButton setImage:pauseImageH forState:UIControlStateHighlighted];
    }else{
		UIImage *playImage = [UIImage imageNamed:@"playing_btn_play_n.png"];
		UIImage *playImageH = [UIImage imageNamed:@"playing_btn_play_h.png"];
        [_playButton setImage:playImage forState:UIControlStateNormal];
        [_playButton setImage:playImageH forState:UIControlStateHighlighted];
    }
}
- (void)btnClick:(UIButton *)btn{
    if (_isPlaying) {
        [_player pause];
    }else{
        [_player play];
    }
    _isPlaying =! _isPlaying;
    [self changeUIState];
}
@end
复制代码

远程控制实例效果

这次笔记贴了很多代码,是因为这两个事件使用简单,理论知识不多,光讲理论,也不好理解,贴代码非常直观。

文章分类
阅读
文章标签