iOS 调用相册

选中某个图片后，显示出来。
- (void)showPicker
{
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
    picker.delegate = self;
    [self presentModalViewController:picker animated:YES];
    [picker release];

}

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];


    UIButton *button = [UIButton buttonWithType: UIButtonTypeRoundedRect];
    button.frame = CGRectMake(10.0f, 60.0f, 120.0f, 30.0f);
    [button setTitle:  @"Picker" forState: UIControlStateNormal];
    [button addTarget: self action: @selector(showPicker) forControlEvents: UIControlEventTouchUpInside];
    [self.view addSubview: button];


    m_imageView = [[UIImageView alloc] initWithImage: nil];
    m_imageView.frame = CGRectMake(120.0f, 120.0f, 60.0f, 60.0f);
    [self.view addSubview: m_imageView];


}


#pragma mark delegate
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)aImage editingInfo:(NSDictionary *)editingInfo
{

    m_imageView.image = aImage;

    [picker dismissModalViewControllerAnimated:YES];

}