android – 如何将图像保存到外部存储器而不是保存在内部

我不明白为什么人们说这是保存在外部存储器,因为当我使用这个代码,我签入我的SD卡没有文件

代码这个

OutputStream imageFileOS;
        int imageNum = 0;
        Intent imageIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
        File imagesFolder = new File(Environment.getExternalStoragePublicDirectory( Environment.DIRECTORY_PICTURES),"Punch");
        if(!imagesFolder.exists()){
            imagesFolder.mkdirs(); // <----
        }
        String fileName = "image_" + String.valueOf(imageNum) + ".jpg";
        File output = new File(imagesFolder,fileName);
        while (output.exists()){
            imageNum++;
            fileName = "image_" + String.valueOf(imageNum) + ".jpg";
            output = new File(imagesFolder,fileName);
        }
        Uri uriSavedImage = Uri.fromFile(output);
        imageIntent.putExtra(MediaStore.EXTRA_OUTPUT,uriSavedImage);

当我运行代码并检查时,它有“内存/图片/打孔/图像_0.jpg”中的文件
但在SD卡中看不到(SD卡=外部存储卡16 GB)
请帮我 ..

解决方法

我认为你对getExternalStorageDirectory的作用感到困惑.

它获取由设备制造商指定的主存储目录.这通常是“sdcard”.注释中指定的“External_sd”实际上是辅助存储目录,不会在给定方法中返回.

这仍然不是受保护的内部存储,并且可以在连接时由Pcs安装和访问.

来自android文档：

Note: don’t be confused by the word “external” here. This directory can better be thought as media/shared storage. It is a filesystem that can hold a relatively large amount of data and that is shared across all applications (does not enforce permissions). Traditionally this is an SD card,but it may also be implemented as built-in storage in a device that is distinct from the protected internal storage and can be mounted as a filesystem on a computer.