Develop Reference

How to open a directory which contains subdirectory in android?

can I open android directory mounted on sdcard should contain sub directories.
for example in ashish directory i had talasu and ash subdirectories.
The code which I had return :-
String root = Environment.getExternalStorageDirectory().toString();
File file = new File(root + "/ashish");

yes you can access those directories, heres a little code to help you out
File[] c = f.listFiles();//where f is your root directory(ashish)
if (c != null) {
for (int i = 0; i < c.length; i++) {
if (c[i].isDirectory()) {
//do whatever you want to do with subdirectories
}

Android: How to list all the files in a directory in to an array?

I have a variable "directorypath". It has the path to a directory in sd card.
Ex: "sdcard/images/scenes"
Now, I want to list all the files in the "directorypath" and want an Array to store all the file names in it.
Ex: Array[0]= Filename1, Array[1]= Filename2 Etc...
I tried something like Array[] myArray = directorypath.listfile(); but didn't work..!
Can anyone give me the code or at least help me? Much appreciated.

I think the problem you are facing is related to the external storage directory file path. Don't use whole path as variable if you can access with environment.
String path = Environment.getExternalStorageDirectory().toString()+"/images/scenes";
Also, you can use the API listfiles() with file object and it will work. For eg ::
File f = new File(path);
File file[] = f.listFiles();

Try the following code which may help you
List<File> getListFiles(File parentDir) {
ArrayList<File> inFiles = new ArrayList<File>();
File[] files = parentDir.listFiles();
for (File file : files) {
if (file.isDirectory()) {
inFiles.addAll(getListFiles(file));
} else {
inFiles.add(file);
}
}
return inFiles;
}
This will return you list of files under the directory you specified.
From the File object in list.. you will get all information about files you required.

Try the following code:
File externalStorageDirectory = Environment.getExternalStorageDirectory();
File folder = new File(externalStorageDirectory.getAbsolutePath() + "/FilePath");
File file[] = folder.listFiles();
if (file.length != 0) {
for (int i = 0; i < file.length; i++) {
//here populate your list
}
} else {
//no file available
}

According to your error message "Cannot resolve listFiles()", you are trying to call a method on a String object, when you actually want to be calling that on a File object.
Create a new File object,
String parentDirectory = "path/to/files";
File dirFileObj = new File(parentDirectory);
File[] files = dirFileObj.listFiles();

I was indeed calling a function for improper data type. i.e., listfiles() won't work on String type variable..!!
SO, I created a File type variable and a File[] array to pass the list of files..!
This solved the issue.

its very simple Just two lines of code
File mListofFiles = new File(Environment.getExternalStorageDirectory.getAbsolutePath()+"/",childpath:Foldername);
File f = new File(mListofFiles.toString());
File file[] = f.listFiles();

File not deleting successfully in android

I have several image files in my sdcard inside the folder req_images. I want to delete all the image files in this folder. So I wrote the following code. The arraylist f stores the list of all image files in it in the form /mnt/sdcard/req_images/Image-1.jpg. When I try to delete all the files one by one using the for loop, the files are not deleting from my sd card. The boolean result which I get as output was false while I try to delete all the files. The file is still there in the sd card and I have checked it. What is the possible error in it.
ArrayList<String> f = new ArrayList<String>(); // list of available files in path
File[] listFile;
public void getSdcardImages()
{
File file= new File(android.os.Environment.getExternalStorageDirectory(),"req_images");
if (file.isDirectory())
{
listFile = file.listFiles();
for (int i = 0; i < listFile.length; i++)
{
f.add(listFile[i].getAbsolutePath());
}
}
}
for(int h=0;h<f.size();h++)
{
File fil=new File(f.get(h));
Boolean bool= fil.delete();
Log.d("File deletion status"+h,bool.toString());
}

Instead of doing it this way try a different approach
File dir = new File(Environment.getExternalStorageDirectory() + "/req_images");
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i = 0; i < children.length; i++) {
new File(dir, children[i]).delete();
}
}

How to get count of images stored in SD card

I need to calculate the number of images stored in SD card and so i would like to name the images unique like Sample0,Sample1,Sample2,Sample3,etc.
Is it Possible?

It gives the number of images present in the images folder of your SD card:
File dir = new File(Environment.getExternalStorageDirectory()
+ "/images");
File[] files = dir.listFiles();
int numberOfImages=files.length;

I now it's been a long time, but, the method above would give you the number of any kind of files and directories within images folder, not only the images number, and doesn't look for images in subfolders inside the images directory.
Let's say we have this structure:
Images/
- img1.jpg
- img2.jpg
- data.dat
- whatever.pdf
- Folder/
- img3.png
The method above will give you 5 and you should obtain 3 isn't it?
I've been working on something similar and I'm pretty sure there is a more efficient way, but with this method I get the number of all images within the SDCard, or any given directory and its subfolders...
Here we go:
public int countImgs(File file, int number) {
File[] dirs = file.listFiles();
String name = "";
if (dirs != null) { // Sanity check
for (File dir : dirs) {
if (dir.isFile()) { // Check file or directory
name = dir.getName().toLowerCase();
// Add or delete extensions as needed
if (name.endsWith(".png") || name.endsWith(".jpg")
|| name.endsWith(".jpeg")) {
number++;
}
} else number = countImgs(dir, number);
}
}
return number;
}
Where the param file is the root directory and the number would be 0 at start. So to use it:
int imgNumber = countImgs(Environment.getExternalStorageDirectory(), 0);

it will be an error when files = null when get the count of images stored in SD card
File dir = new File(Environment.getExternalStorageDirectory() + "/images");
File[] files = dir.listFiles();
String strnumberOfImages=files.length;
int intnumberOfImages= 0;
try{
intnumberOfImages = Integer.parseInt( strnumberOfImages);
}catch ( Exception e ){
intnumberOfImages = 0;
}
if just check empty or not
File dir = new File(Environment.getExternalStorageDirectory()+ "/images");
File[] files = dir.listFiles();
if(files != null){
// there are picz
}else{
// sd card empty
}

Showing a list of files in a ListView

I'm wondering how to show files from a directory in a ListView`. The files can be listed with:
File dir = new File(dirPath);
File[] filelist = dir.listFiles();
and added to the ListView via ArrayAdapter but I don't get the usage of the ArrayAdapter.

I guess you want to show the names of the files from that directory so you could try this:
File dir = new File(dirPath);
File[] filelist = dir.listFiles();
String[] theNamesOfFiles = new String[filelist.length];
for (int i = 0; i < theNamesOfFiles.length; i++) {
theNamesOfFiles[i] = filelist[i].getName();
}
The adapter to use with the list :
new ArrayAdapter<String>(this, android.R.layout.simple_list_item, theNamesOfFiles);
For anything more complicated than showing the names of the files you have to implement a custom adapter.

Or you can use something like this for a sorted String of filenames:
File dataDirectory = Environment.getDataDirectory();
File fileDir = new File(dataDirectory, "data/com.yourapp.app/files");
String[] listItems = fileDir.list();
Arrays.sort(listItems);