If you're trying to access images on the device, the best method is to use the MediaStore content provider. Accessing it as a content provider will allow you to query the images that are present, and map content://
URLs to filepaths on the device where appropriate.
If you still need to access the SD card, the Camera application includes an ImageUtils class that checks if the SD card is mounted as follows:
static public boolean hasStorage(boolean requireWriteAccess) {
//TODO: After fix the bug, add "if (VERBOSE)" before logging errors.
String state = Environment.getExternalStorageState();
Log.v(TAG, "storage state is " + state);
if (Environment.MEDIA_MOUNTED.equals(state)) {
if (requireWriteAccess) {
boolean writable = checkFsWritable();
Log.v(TAG, "storage writable is " + writable);
return writable;
} else {
return true;
}
} else if (!requireWriteAccess && Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
return true;
}
return false;
}
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