iOS开发 调用系统相机和相册

 调用系统相机和相册 （iPad，iPhone）
打开相机：（iPad，iPhone）
//先设定sourceType为相机，然后判断相机是否可用（ipod）没相机，不可用将sourceType设定为相片库  
    UIImagePickerControllerSourceType sourceType = UIImagePickerControllerSourceTypeCamera;  
//    if (![UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypeCamera]) {  
//        sourceType = UIImagePickerControllerSourceTypePhotoLibrary;  
//    }  
    //sourceType = UIImagePickerControllerSourceTypeCamera; //照相机  
    //sourceType = UIImagePickerControllerSourceTypePhotoLibrary; //图片库  
    //sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum; //保存的相片  
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];//初始化  
    picker.delegate = self;  
    picker.allowsEditing = YES;//设置可编辑  
    picker.sourceType = sourceType;  
    [self presentModalViewController:picker animated:YES];//进入照相界面  
    [picker release];  

打开相册：（区分pad和iphone）for iphone：
UIImagePickerController *pickerImage = [[UIImagePickerController alloc] init];  
    if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {  
        pickerImage.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;  
        //pickerImage.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;  
        pickerImage.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:pickerImage.sourceType];  
          
    }  
    pickerImage.delegate = self;  
    pickerImage.allowsEditing = NO;  
    [self presentModalViewController:pickerImage animated:YES];  
    [pickerImage release];  

打开相册for ipad:
UIImagePickerControllerSourceType sourceType = UIImagePickerControllerSourceTypePhotoLibrary;  
    //sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum; //保存的相片  
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];  
    picker.delegate = self;  
    picker.allowsEditing = NO;//是否允许编辑  
    picker.sourceType = sourceType;  
    /* 
     如果从一个导航按钮处呈现，使用： 
     presentPopoverFromBarButtonItem:permittedArrowDirections:animated:； 
     如果要从一个视图出呈现，使用： 
     presentPopoverFromRect:inView:permittedArrowDirections:animated: 
      
     如果设备旋转以后，位置定位错误需要在父视图控制器的下面方法里面重新定位： 
     didRotateFromInterfaceOrientation:（在这个方法体里面重新设置rect） 
     然后再次调用： 
     - (void)presentPopoverFromRect:(CGRect)rect inView:(UIView *)view permittedArrowDirections:(UIPopoverArrowDirection)arrowDirections animated:(BOOL)animated              
     */  
    //UIPopoverController只能在ipad设备上面使用；作用是用于显示临时内容，特点是总是显示在当前视图最前端，当单击界面的其他地方时自动消失。  
    UIPopoverController *popover = [[UIPopoverController alloc]initWithContentViewController:picker];  
    self.imagePicker = popover;  
    //permittedArrowDirections 设置箭头方向  
    [self.imagePicker presentPopoverFromRect:CGRectMake(0, 0, 300, 300) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];  
    [picker release];  
    [popover release];  

点击相册中的图片 货照相机照完后点击use
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

点击cancel 调用的方法
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker

注意：需要添加@property (nonatomic, retain) UIPopoverController *imagePicker;