How to make double seekbar in android?

I am building an android application where the user select the a maximum value by seekbar.

I need another button on the same seekbar so that user can select maximum and minimum value from a particular unique seekbar.

Here is my code of single seek bar -

package com.ui.yogeshblogspot;

public class CustomSeekBarExActivity extends Activity implements OnSeekBarChangeListener{
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
 SeekBar bar=(SeekBar)findViewById(R.id.seekBar1);
 bar.setOnSeekBarChangeListener(this);
}

@Override
public void onProgressChanged(SeekBar seekBar, int progress,
        boolean fromUser) {
    // TODO Auto-generated method stub
    TextView tv=(TextView)findViewById(R.id.textView2);
    tv.setText(Integer.toString(progress)+"%");

}

@Override
public void onStartTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub

}

@Override
public void onStopTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub

}
}

Here is my xml code of seek bar -

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" 
android:background="#FFFFFF">

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Choose Your Progress"
    android:textColor="#000000"
    android:textAppearance="?android:attr/textAppearanceMedium" />

<SeekBar
    android:id="@+id/seekBar1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" 
    android:layout_gravity="center"
    android:progressDrawable="@xml/progress"
    android:max="100"
    android:thumb="@xml/thumb"/>

<TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textColor="#000000"
    android:gravity="center"
    android:layout_gravity="center"
    android:paddingTop="10dp"
    android:textAppearance="?android:attr/textAppearanceMedium" />

</LinearLayout>

The Android widget class library has only one slider control, seekbar with only one thumb control. Did some research online and found this cool custom widget, range-seek-bar.

you can followed any one of below

https://github.com/edmodo/range-bar

https://code.google.com/p/range-seek-bar/

https://github.com/Larpon/RangeSeekBar