How to create a project folder under an external SD card by Android5.1

now the demand is to read and write to the external SD card, but after Android4.4, the external SD card does not have read and write permission, and the only one with read and write permission is the storage/sdcard2/Android/data/PACKAGE_NAME/ folder, but after the APP is installed, the PACKAGE_NAME folder does not have
automatic generation. It is possible to build a directory manually in file management. Is there any way to make it generate automatically? Or there are other ways to read and write external SD cards

Java android

Sep.29,2021

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