Develop Reference

The directory construction of Android

I list a directory construction of Android.
I find the directory are same when list directory with these path /sdcard, /storage/sdcard0, /storage/emulated/legacy/and storage/emulated/0/, why?
The function Environment.getExternalStorageDirectory() can return /storage/emulated/0, I hope to return /storage/extSdCard/, which funation should I use?
In my android mobile phone, the /storage/extSdCard/ point to a removable SD card, does the SD card belong to External Storage ? You know storage/emulated/0/ point to my phone memory Card! What are different between extSdCard and External Storage ?
Root
sdcard
storage
storage/sdcard0/
storage/emulated/0/
storage/extSdCard/

How to get path of Android shared Directories in internal/primary storage not SD card?

I want to show android file system just like file browser and want to show shared folder path so that if someone download some stuff in that folder then that data persist even after uninstall of my app.
Here is what I am using:
file = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
This try to return path from SD card, and don't work if there is no sdcard mounted.
So I want to know that how can I show the downloads directory or other shared directory path that is on my device or on emulator without an sd card.
I saw this function:
public static File getDownloadCacheDirectory ();
But i think this is just a cache directory and not actual download directory.
I am using astro file manager on my device which don't have SD card. In astro file manager when I click on Downloads directory, it first show mnt/sdcard/Downloads for a moment in address bar and then go to internal path similar to [Flash/sd card storage icon]/Primary/Downloads. So I want to know that how I can get that primary path in case external storage is not available?
Please let me know how I can do that or else point me towards some good resource where I can find about it.

Where in Android file system are directories created?

I am working on Android app that has to save data to files. To make the files accessible for all apps and also transfer to computer through USB, the files should be saved in a folder called "ABC". I manually created the folder "ABC" on both external storage card and internal storage. I was able to get full path of that folder on external storage card through code and was able to write and read from it.
String path = Environment.getExternalStorageDirectory().toString() + "/ABC";
But the internal storage turns out to be more elusive because I could not get the full path of "ABC" folder on the internal storage. Is there a way to programmatically determine where folders are created on internal storage? Generally, under what partion are folders created on internal storage in Android?
Edit:
Internal storage - I mean non-removable storage
External Storage - I mean Removable storage

I manually created the folder "ABC" on both external storage card and internal storage.
You might have created this directory on external storage. Unless you are testing on a device or emulator, you did not create this directory on internal storage, as you do not have access to it. A "card" would imply removable storage, which is something else entirely, for the vast majority of Android devices.
I was able to get full path of that folder on external storage card through code and was able to write and read from it.
Your code is for external storage. On very few devices is that a "card".
But the internal storage turns out to be more elusive because I could not get the full path of "ABC" folder on the internal storage.
There is no "ABC" folder on internal storage, insofar as you cannot create a /ABC directory off of the device root, or even off of /data. You can only work for your app's portion of internal storage, using methods like getFilesDir(). And, again, unless you are testing on an emulator or a rooted device, you have no means of creating such an "ABC" directory by hand.
Is there a way to programmatically determine where folders are created on internal storage?
Um, well, you are certainly welcome to examine the path in the File object that you created to point to some location (e.g., new File(getFilesDir(), "ABC")).
Generally, under what partion are folders created on internal storage in Android?
/data.

Get external sdcard in android phone

I got the both the external and internal(phone memory ) SD card in listing in my application
but along with that i got some more folder and i don't want them so how can i limit to external and internal SD card only in listing...
i provided the root directory which is /storage and it displays whole the folder...
or can some one tell me how to get external sd card programmaticaly
i have tried the usual way File file = Environment.getExternalStorageDirectory();
given by android but it returned only internal path .

Environment.getExternalStorageDirectory() it returns sd card path but depends on the device
for better under standing check Find an external SD card location

how to accees Environment.getExternalStorageDirectory() when user connected to system

I am working on email application. My application will create some files in the Sd card.
I am using
Environment.getExternalStorageDirectory()
to store the files in SD card. But I have observed that some times when my device connected to my computer I am unable to access my files.
Please suggest what's the path I need to use so that my files must always accessible.
I want to store my files only in Sd card.

I think when the SD card is mounted you cannot access it.