这可能对您有所帮助.在 sdcard 上写入文件时，我遇到了同样的问题.我已经设置了写入文件所需的所有权限，但我使用了如下所示的文件对象:

This may help you. I face the same issue when writing the file on sdcard. I have set all required permission to write the file but I used the file object like below:

错误:

File myFile = new File(Environment.getExternalStorageDirectory().getAbsoluteFile()+fileName);

正确:

File myFile = new File(Environment.getExternalStorageDirectory().getAbsoluteFile(), fileName);

那说明路径不对.