Implement a simple File Explorer in Android

It's a simple File Explorer in Android.



The files information can be read using java.io.File, using the code:
File f = new File(dirPath);
File[] files = f.listFiles();

The name of the files/folders will be added in a ArrayList. If it's not the root, two more elements (the root and the parent) will be added in the front of the ArrayList.

Then, the ArrayList will be adapted to a ArrayAdapter, and also set to be displayed on screen.

In case any item is clicked; if it's a file, the name will be display in a dialog; if it's a directory (isDirectory) and can be read (canRead), will open the selected directory; if it's a directory and CANNOT be read, a message will be prompt.




Create a layout file /res/layout/row.xml, which is the layout of each row the the list.

<?xml version="1.0" encoding="utf-8"?>
<TextView 
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/rowtext"
  android:layout_width="fill_parent"
     android:layout_height="25px"
     android:textSize="23sp" />

Modify /res/layout/main.xml to have a List:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
 android:id="@+id/path"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    />
<ListView
 android:id="@android:id/list"
 android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
 />
<TextView
 android:id="@android:id/empty"
 android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="No Data"
 />
</LinearLayout>

remark: TextView with id empty will be display IF the list is empty.

Modify the code, AndroidExplorer.java

package com.AndroidExplorer;

import java.io.File;
import java.util.ArrayList;
import java.util.List;
import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class AndroidExplorer extends ListActivity {
 
 private List<String> item = null;
 private List<String> path = null;
 private String root="/";
 private TextView myPath;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        myPath = (TextView)findViewById(R.id.path);
        getDir(root);
    }
    
    private void getDir(String dirPath)
    {
     myPath.setText("Location: " + dirPath);
     
     item = new ArrayList<String>();
     path = new ArrayList<String>();
     
     File f = new File(dirPath);
     File[] files = f.listFiles();
     
     if(!dirPath.equals(root))
     {

      item.add(root);
      path.add(root);
      
      item.add("../");
      path.add(f.getParent());
            
     }
     
     for(int i=0; i < files.length; i++)
     {
       File file = files[i];
       path.add(file.getPath());
       if(file.isDirectory())
        item.add(file.getName() + "/");
       else
        item.add(file.getName());
     }

     ArrayAdapter<String> fileList =
      new ArrayAdapter<String>(this, R.layout.row, item);
     setListAdapter(fileList);
    }

 @Override
 protected void onListItemClick(ListView l, View v, int position, long id) {
  
  File file = new File(path.get(position));
  
  if (file.isDirectory())
  {
   if(file.canRead())
    getDir(path.get(position));
   else
   {
    new AlertDialog.Builder(this)
    .setIcon(R.drawable.icon)
    .setTitle("[" + file.getName() + "] folder can't be read!")
    .setPositiveButton("OK", 
      new DialogInterface.OnClickListener() {
       
       @Override
       public void onClick(DialogInterface dialog, int which) {
        // TODO Auto-generated method stub
       }
      }).show();
   }
  }
  else
  {
   new AlertDialog.Builder(this)
    .setIcon(R.drawable.icon)
    .setTitle("[" + file.getName() + "]")
    .setPositiveButton("OK", 
      new DialogInterface.OnClickListener() {
       
       @Override
       public void onClick(DialogInterface dialog, int which) {
        // TODO Auto-generated method stub
       }
      }).show();
  }
 }
}

Download the files.