iOS開發圖片的基本選取

- (IBAction)selectPhoto:(id)sender
{

    UIActionSheet *_sheet = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:@"取消" destructiveButtonTitle:nil otherButtonTitles:@"打開照相機", @"從相冊中獲取", nil];
    [_sheet showInView:self.view];

}
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex{

    switch (buttonIndex) {
        case 0:
            //選擇照相機
            [self takePhoto];
            break;
        case 1:
            //選擇相冊
            [self LocalPhoto];
            break;
        default:
            break;
    }
}

- (void)takePhoto
{
    UIImagePickerControllerSourceType sourcType = UIImagePickerControllerSourceTypeCamera;
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
        UIImagePickerController *picker = [[UIImagePickerController alloc]init];
        picker.delegate = self;
        picker.sourceType = sourcType;
        [self presentViewController:picker animated:YES completion:^{

        }];

    }else{
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"無法調取相機，請檢查" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"確定", nil];
        [alert show];
        return;
    }

}

- (void)LocalPhoto
{
    // 1. 實例化照片選擇控制器
    UIImagePickerController *imagePicker = [[UIImagePickerController alloc]init];
    // 2. 設置照片源
    [imagePicker setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];
    // 3. 設置是否允許編輯
    [imagePicker setAllowsEditing:YES];
    // 4. 設置代理
    [imagePicker setDelegate:self];
    // 5. 顯示照片選擇控制器
    [self presentViewController:imagePicker animated:YES completion:nil];

}

#pragma mark - 照片選擇代理方法
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    // 1. 獲取編輯後的照片
    UIImage *image;
    switch (picker.sourceType) {
        case UIImagePickerControllerSourceTypeCamera:
            image = info[@"UIImagePickerControllerOriginalImage"];
            //將圖片保存到相冊
            [self saveImageToPhotos:image];
            break;
        case UIImagePickerControllerSourceTypePhotoLibrary:
            image = info[@"UIImagePickerControllerEditedImage"];
            break;
        default:
            break;
    }
    // 2. 設置按鈕的圖像
    [_photoButton setImage:image forState:UIControlStateNormal];
    // 3. 關閉照片選擇控制器
    [self dismissViewControllerAnimated:YES completion:nil];
}

//將圖片保存到相冊
- (void)saveImageToPhotos:(UIImage*)savedImage
{
    UIImageWriteToSavedPhotosAlbum(savedImage, self, @selector(image:didFinishSavingWithError:contextInfo:), NULL);
}

// 指定回調方法
- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    NSString *msg = nil ;
    if(error != NULL){
        msg = @"保存圖片失敗" ;
    }else{
        msg = @"保存圖片成功" ;
    }
     UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"保存圖片結果提示" message:msg delegate:nil cancelButtonTitle:@"確定" otherButtonTitles:nil, nil];
    [alert show];
}