IOS获取摄像和本地中的资源

上传文件时，我们都的从本地中选择或用相机来拍摄得到文件。

一个上传按钮，单击事件

 1 -(IBAction)btnClick{
 2    UIActionSheet* actionSheet = [[UIActionSheet alloc]
 3                                                initWithTitle:@"请选择文件来源"
 4                                                     delegate:self
 5                                        cancelButtonTitle:@"取消"
 6                                 destructiveButtonTitle:nil
 7                                        otherButtonTitles:@"照相机",@"摄像机",@"本地相簿",@"本地视频",nil];
 8             [actionSheet showInView:self.view];
 9             [actionSheet release];
10 }

点击按钮触发的btnClick事件后将会弹出一个如下的选择筐：

接下来将要为UIActionSheet实现其中的委托了。

 1 #pragma mark -
 2 #pragma UIActionSheet Delegate
 3 - (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
 4 {   
 5     NSLog(@"buttonIndex = [%d]",buttonIndex);
 6     switch (buttonIndex) {
 7         case 0://照相机
 8             {10                 UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
11                 imagePicker.delegate = self;
12                 imagePicker.allowsEditing = YES;
13                 imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
14                 imagePicker.mediaTypes =  [[NSArray alloc] initWithObjects: (NSString *) kUTTypeImage, nil];
15                 [self presentModalViewController:imagePicker animated:YES];
16                 [imagePicker release];
17             }
18             break;
19         case 1://摄像机
20             {22                 UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
23                 imagePicker.delegate = self;
24                 imagePicker.allowsEditing = YES;
25                 imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
26                 imagePicker.mediaTypes = [[NSArray alloc] initWithObjects: (NSString *) kUTTypeMovie, nil];
27                 imagePicker.videoQuality = UIImagePickerControllerQualityTypeLow;
28                 [self presentModalViewController:imagePicker animated:YES];
29                 [imagePicker release];
30             }
31             break;
32         case 2://本地相簿
33             {35                 UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
36                 imagePicker.delegate = self;
37                 imagePicker.allowsEditing = YES;
38                 imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
39                 imagePicker.mediaTypes =  [[NSArray alloc] initWithObjects: (NSString *) kUTTypeImage, nil];
40                 [self presentModalViewController:imagePicker animated:YES];
41                 [imagePicker release];
42             }
43             break;
44         case 3://本地视频
45             {47                 UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
48                 imagePicker.delegate = self;
49                 imagePicker.allowsEditing = YES;
50                 imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
51                 imagePicker.mediaTypes =  [[NSArray alloc] initWithObjects: (NSString *) kUTTypeMovie, nil];
52                 [self presentModalViewController:imagePicker animated:YES];
53                 [imagePicker release];
54             }
55             break;
56         default:
57             break;
58     }
59 }

实现了UIActionSheet的委托后，要发现，我们使用了UIImagePickerController，这个类将帮我们实现选取文件，打开对应的选取方式。比如当ButtonIndex为0的时候，它将帮我们打开照相机，我们可以使用相机拍摄照片作为上传的选取文件。因此，在这里我们还要实现UIImagePickerController的委托：

 1 #pragma mark - 
 2 #pragma UIImagePickerController Delegate
 3 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
 4 {
 5     if ([[info objectForKey:UIImagePickerControllerMediaType] isEqualToString:(NSString*)kUTTypeImage]) {
 6         UIImage  *img = [info objectForKey:UIImagePickerControllerEditedImage];
 7         self.fileData = UIImageJPEGRepresentation(img, 1.0);
 8     } else if ([[info objectForKey:UIImagePickerControllerMediaType] isEqualToString:(NSString*)kUTTypeMovie]) {
 9         NSString *videoPath = [[info objectForKey:UIImagePickerControllerMediaURL] path];
10         self.fileData = [NSData dataWithContentsOfFile:videoPath]; 
11     }
12     [picker dismissModalViewControllerAnimated:YES];
13 }
14 
15 - (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker 
16 {
17     [picker dismissModalViewControllerAnimated:YES];
18 }

之后，你选取的文件便保存在了filedata中。就可以随时过来调用了。