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android - Check if the SDCard is present, boolean is always true

In my splash screen, I want to check if the phone has a SDCard. The Boolean statement is beneath:

    Boolean isSDPresent = android.os.Environment.getExternalStorageState()
            .equals(android.os.Environment.MEDIA_MOUNTED );

So, if I have the SDCard in the slot on my phone, this boolean will return true, so far so good. When I go to the "Unmount SDCard" from the settings menu, and removes the SDCard, then kill the app and launching it again, the boolean will also be true..

And if I launches the Astro File Manager after unmounting and removing the sdcard, I can still access the /mnt/sdcard path, why?

How can I manage to accomplish this?

Thanks in advance!

EDIT

Testing with the following code:

File path = Environment.getExternalStorageDirectory(); 
String pathS = path.getPath();

When the SDCard is in the slot, the pathS contains mnt/sdcard, but when I removes the SDCard the pathS is still /mnt/sdcard ...

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I've found that phones, like the Galaxy phones from Samsung, have /mnt/sdcard point to internal memory and not the external SD card as expected.

You can know if the path returned by Environment.getExternalStorageDirectory() is actually the external SD card with a call to Environment.isExternalStorageRemovable()

Just wanted to add from the docs for getExternalStorageDirectory() this important note:

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.


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