提示iOS用户选择要由应用处理的JPEG答案

【问题标题】：Prompt iOS user to select JPEG to be processed by app提示iOS用户选择要由应用处理的JPEG
【发布时间】：2019-07-22 20:35:57
【问题描述】：

我已经在 Android 中完成了此操作，但似乎无法找到有关在 iOS 中执行此操作的任何信息。基本上：

Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/JPEG");
Intent i = Intent.createChooser(intent, "File");
startActivityForResult(i, CHOOSE_FILE_REQUESTCODE);

然后

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // Check which request we're responding to
    if (requestCode == CHOOSE_FILE_REQUESTCODE) {
        // Make sure the request was successful
        if (resultCode == RESULT_OK) {
            // The user picked a contact.
            // The Intent's data Uri identifies which contact was selected.

            // Do something with the contact here (bigger example below)
        }
    }
}

对应的术语和示例代码是什么/在哪里？

（感谢 Objective-C 示例）

【问题讨论】：

标签： ios objective-c xcode

【解决方案1】：

iOS 中的 UIImagePickerController 视图控制器是允许用户从媒体库中选择图片的标准方式。有关这方面的 Apple 文档可在 UIImagePickerController. 获得。还有一个很好的教程，显示如何在 Picking images with UIImagePickerController in Swift 5 使用 UIImagePickerController。

【讨论】：

感谢参考+1

【解决方案2】：

这正是您要查找的内容：https://stackoverflow.com/a/41717882/2968456

基本上你需要使用苹果内置的 UIImagePicker 框架。

【讨论】：

感谢参考+1

【解决方案3】：

Credit 主要参考其他答案，但这里是 Objective-C 示例代码：

UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
presentViewController:picker animated:YES completion:nil];

图像数据回调：

/*============================================================================*/

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

/*============================================================================*/
{
    [picker dismissViewControllerAnimated:YES completion:nil];
    [picker release];

    UIImage* image = [info objectForKey:UIImagePickerControllerEditedImage];
    if (!image)
        image = [info objectForKey:UIImagePickerControllerOriginalImage];

    NSData* imgData = UIImageJPEGRepresentation(image, 1.0);
    NSLog(@"Size of Image(bytes):%lu",(unsigned long)[imgData length]);
}

代表/self 必须是：

UIViewController <UINavigationControllerDelegate, UIImagePickerControllerDelegate>

【讨论】：