UIImagePickerController的用法

在实际的APP开发中,我们经常会见到应用的这样的功能 :需要选取手机相册的照片,还有选取视频,拍视频和照相的操作.
在iOS开发中,实现以上的功能就需要用到 UIImagePickerController.
现将 UIImagePickerController的基本用法总结如下 :
  1 #import "ViewController.h"
  2 
  3 @interface ViewController ()<UIImagePickerControllerDelegate,UINavigationControllerDelegate>
  4 
  5 //拍照
  6 - (IBAction)takePhoto:(id)sender;
  7 
  8 //拍电影
  9 - (IBAction)takeMovie:(id)sender;
 10 
 11 @property (weak, nonatomic) IBOutlet UIImageView *imgView;
 12 
 13 //选择照片
 14 - (IBAction)selectPhoto:(id)sender;
 15 
 16 //选择视频
 17 - (IBAction)selectVideo:(id)sender;
 18 
 19 
 20 @end
 21 
 22 @implementation ViewController
 23 
 24 - (void)viewDidLoad {
 25     [super viewDidLoad];
 26     
 27     //UIImagePickerController.访问用户相册 2.拍照,拍视频
 28     
 29 }
 30 
 31 //1.选取照片
 32 - (IBAction)selectPhoto:(id)sender {
 33     
 34     UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
 35     
 36     /*
 37     UIImagePickerControllerSourceTypePhotoLibrary,获取相册中所有的文件
 38     UIImagePickerControllerSourceTypeCamera,摄像头
 39     UIImagePickerControllerSourceTypeSavedPhotosAlbum,系统内置相册
 40      */
 41 
 42     //资源类型(资源来自哪里,可以来相册,摄像头)
 43     imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
 44     
 45     //设置代理
 46     imagePickerCtrl.delegate = self;
 47     
 48     //弹出控制器
 49     [self presentViewController:imagePickerCtrl animated:YES completion:^{
 50        
 51         //弹出控制器完成调用的方法
 52     }];
 53     
 54 }
 55 /**
 56  *
 57  * 2.选取视频
 58  */
 59 - (IBAction)selectVideo:(id)sender {
 60     
 61      UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
 62     
 63     imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
 64     imagePickerCtrl.delegate = self;
 65     
 66     //指定媒体类型,图片(@"public.image"),视频(@"public.movie")
 67     imagePickerCtrl.mediaTypes = @[/*@"public.image",*/@"public.movie"];
 68     
 69     [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
 70     
 71     
 72 }
 73 
 74 //3.拍照
 75 - (IBAction)takePhoto:(id)sender {
 76 
 77     UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
 78     
 79     imagePickerCtrl.delegate = self;
 80     
 81     //判断手机是否支持(前)摄像头
 82     if (![UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront]) {
 83         
 84         UIAlertView *alerView = [[UIAlertView alloc] initWithTitle:@"提示" message:@"手机太渣,没有摄像头" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
 85         [alerView show];
 86         
 87         return;
 88     }
 89     
 90     //指定资源来自摄像头
 91     imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeCamera;
 92     
 93     [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
 94     
 95 
 96 }
 97 
 98 //4.拍视频
 99 - (IBAction)takeMovie:(id)sender {
100     
101     UIImagePickerController *imagePickerCtrl = [[UIImagePickerController alloc] init];
102     
103     imagePickerCtrl.delegate = self;
104 
105     //指定资源来自摄像头
106     imagePickerCtrl.sourceType = UIImagePickerControllerSourceTypeCamera;
107     
108     //设置资源类型
109     imagePickerCtrl.mediaTypes = @[@"public.movie"];
110     
111     [self presentViewController:imagePickerCtrl animated:YES completion:NULL];
112 }
113 
114 #pragma mark UIImagePickerControllerDelegate
115 //选取完视频,或者照片调用的协议方法(不管是拍照,选相册,拍视频,选视频,最终都会调用此方法)
116 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
117 
118     NSLog(@"%@",info);
119     
120     //取出选择的照片
121     UIImage *img = info[UIImagePickerControllerOriginalImage];
122     
123     //将选取的照片交给_imgView显示
124     _imgView.image = img;
125     
126     
127     //如果资源来自摄像头
128     if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
129         
130         //将图片存到相册中调用的方法  (苹果建议的写法:好像必须要这样写)
131         //- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
132         
133         UIImageWriteToSavedPhotosAlbum(img, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
134     }
135     
136     //如果选中的是视频则可以通过UIImagePickerControllerMediaURL在字典中获取到选中的视频的URL
137    
138     //选取照片或视频后,关闭控制器
139     [picker dismissViewControllerAnimated:YES completion:NULL];
140     
141 }
142 
143 //"取消"按钮被点击
144 - (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {
145 
146     NSLog(@"被关闭了");
147     [picker dismissViewControllerAnimated:YES completion:NULL];
148 
149 }
150 
151 - (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{
152     
153     NSLog(@"照片保存到相册成功");
154 }
155 
156 @end
这种写法的缺点就是,选取图片的时候只能选取一张照片,如果要选取多张照片的话,就需要用到另外一种方法 AssetsLibrary
AssetsLibrary的基本用法随后更新!!! 记得关注我哟!!!!