How to get the internal and external sdcard path in android

Question

Most of the new android devices have an internal sdcard and an external sdcard. I want to make a file explorer app but I can\'t find out how to get the path to use in my app

Answer 1

I'm not sure how general an answer this but I tested it on a motorola XT830C with Android 4.4 and on a Nexus 7 android 6.0.1. and on a Samsung SM-T530NU Android 5.0.2. I used System.getenv("SECONDARY_STORAGE") and Environment.getExternalStorageDirectory().getAbsolutePath().
The Nexus which has no second SD card, System.getenv returns null and Envirnoment.getExterna... gives /storage/emulated/0.
The motorola device which has an external SD card gives /storage/sdcard1 for System.getenv("SECONDARY_STORAGE") and Envirnoment.getExterna... gives /storage/emulated/0.
The samsumg returns /storage/extSdCard for the external SD.
In my case I am making a subdirectory on the external location and am using

 appDirectory = (System.getenv("SECONDARY_STORAGE") == null)
       ? Environment.getExternalStorageDirectory().getAbsolutePath()
       : System.getenv("SECONDARY_STORAGE");

to find the sdcard. Making a subdirectory in this directory is working.
Of course I had to set permission in the manifest file to access the external memory.
I also have a Nook 8" color tablet. When I get a chance to test on them, I'll post if I have any problems with this approach.