Android : How can i adding ClipBoard in Android

i have 2 EditText and 4 button.and i need when, user clicked on first button, (from edittext1), output string sended in edit text2 and then, i can copyed output string in clipboard on android. this is my try in MainActivity :

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.Dialog;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

/** Called when the activity is first created. */

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);


    public class MainActivity extends Activity {
Button copy,paste;
EditText copyTxt;
TextView pasteTxt;
int sdk = android.os.Build.VERSION.SDK_INT;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    copy = (Button)findViewById(R.id.copy);
    copyTxt = (EditText)findViewById(R.id.copytxt);



    copy.setOnClickListener(new View.OnClickListener() {


      String CopyText;
      @SuppressWarnings("deprecation")
      @Override
      public void onClick(View arg0) {
        // TODO Auto-generated method stub
        CopyText = copyTxt.getText().toString();

        if(CopyText.length() != 0){
        if(sdk < android.os.Build.VERSION_CODES.HONEYCOMB) {

          android.text.ClipboardManager clipboard = (android.text.ClipboardManager) getSystemService(Context.CLIPBOARD_SERVICE);
            clipboard.setText(CopyText);
            Toast.makeText(getApplicationContext(), "Text Copied to Clipboard", Toast.LENGTH_SHORT).show();
        } else {
            android.content.ClipboardManager clipboard = (android.content.ClipboardManager) getSystemService(Context.CLIPBOARD_SERVICE);
            android.content.ClipData clip = android.content.ClipData.newPlainText("Clip",CopyText);
            Toast.makeText(getApplicationContext(), "Text Copied to Clipboard", Toast.LENGTH_SHORT).show();
            clipboard.setPrimaryClip(clip);
        }}else{
            Toast.makeText(getApplicationContext(), "Nothing to Copy", Toast.LENGTH_SHORT).show();
        }














    Button b = (Button) findViewById(R.id.button2);
    b.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
                startActivity(new Intent(MainActivity.this, BruteForceActivity.class));
        }
    });

    Button b1 = (Button) findViewById(R.id.aboutbtn);
    b1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                    Dialog d = new Dialog(MainActivity.this);
                    d.setContentView(R.layout.dialog);
                    String title = getResources().getString(R.string.dialog_title);
                    d.setTitle(title);
                    d.show();
            }
    });

                                                                        //for Showing Dialog.


                final Button bb = (Button) findViewById(R.id.button1);
                bb.setOnClickListener(new OnClickListener() {

                        @SuppressLint("ShowToast")
                        @Override
                            public void onClick(View v) {

                            EditText et = (EditText) findViewById(R.id.editText1);
                            String editText_input = et.getText().toString();

                                                            //Save to String-Name = editText_input
                        String rawString = et.getText().toString();

                      try { 
                        Toast.makeText(MainActivity.this, "It's Done !", 2000).show();
                        EditText editText2 = (EditText) findViewById(R.id.editText2);
                        editText2.setText(AeSimpleMD5.MD5(rawString));
                    } catch (NoSuchAlgorithmException e) { 
                        // TODO Auto-generated catch block 
                        e.printStackTrace();
                    } catch (UnsupportedEncodingException e) { 
                        // TODO Auto-generated catch block 
                        e.printStackTrace();
                    }  

                                                                //need to showing that in editText2.
        }           

                });
 }
 }
 class AeSimpleMD5 {

    private static String convertToHex(byte[] data) {
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < data.length; i++) {
            int halfbyte = (data[i] >>> 4) & 0x0F;
            int two_halfs = 0;
            do {
                if ((0 <= halfbyte) && (halfbyte <= 9))
                    buf.append((char) ('0' + halfbyte));
                else
                    buf.append((char) ('a' + (halfbyte - 10)));
                halfbyte = data[i] & 0x0F;
            } while (two_halfs++ < 1);
        }
        return buf.toString();
    }

    public static String MD5(String text) throws NoSuchAlgorithmException,
            UnsupportedEncodingException {
        MessageDigest md;
        md = MessageDigest.getInstance("MD5");
        byte[] md5hash = new byte[32];
        md.update(text.getBytes("iso-8859-1"), 0, text.length());
        md5hash = md.digest();
        return convertToHex(md5hash);
    }
}
  }
    }}

i used this tutorial for adding clipboard :

http://www.learn2crack.com/2014/01/android-using-clipboard-copy-paste-data.html

i need just, when user clicked on first button, output (md5 hash) sended in textedit2,

and user can copyed in clipboard with Copy(Button). also, i used class AeSimpleMD5 for md5 hash

http://www.anyexample.com/programming/java/java_simple_class_to_compute_md5_hash.xml

.i cant fixed the clipboard. please help.