Program Android Simulasi Lempar atau Tosh Koin

Source code Main.xml

Source code AcakKoinActivity.java

package com.AcakKoin;

import java.text.DecimalFormat;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class AcakKoinActivity extends Activity implements OnClickListener{
    EditText txtlempar;
    TextView angka, gambar, pangka, pgambar;
    int ang, gam=0;
   
	public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        View acak = findViewById(R.id.acak);
        acak.setOnClickListener((OnClickListener) this);
        View clear = findViewById(R.id.clear);
        clear.setOnClickListener((OnClickListener) this);
        txtlempar = (EditText) findViewById(R.id.txtlempar);
        angka = (TextView) findViewById(R.id.angka);
        gambar = (TextView) findViewById(R.id.gambar);
        pangka = (TextView) findViewById(R.id.pangka);
        pgambar = (TextView) findViewById(R.id.pgambar);
    }
    
    public void onClick(View v)
    {
        switch(v.getId())
        {
        case R.id.acak:
        	String lempar = txtlempar.getText().toString();
        	if (lempar.length() != 0) {
        	long n = Long.parseLong(lempar);
          	for (int x = 1; x <= n ; ++x){
        	      double koin = Math.random();
        	      if (koin<=0.5)
        	    	  ang=ang+1;
        	      else
        	    	  gam=gam+1;
            DecimalFormat twoDForm = new DecimalFormat("#.##");
            angka.setText(Long.toString(ang));
        	gambar.setText(Long.toString(gam));
        	double persen=(ang*100.0)/n;
        	double persenbulat = Double.valueOf(twoDForm.format(persen));
           	pangka.setText(Double.toString(persenbulat));
        	pgambar.setText(Double.toString(100-persenbulat));
        	}
        	}
        	else 
        		Toast.makeText(getBaseContext(), 
                "Isi banyaknya acak koin", 
                Toast.LENGTH_SHORT).show();
        	break;
        			
        case R.id.clear:
        	if (angka.length()>0)
        	{
	        	ang=0;
	        	gam=0;
	        	angka.setText("");
	        	gambar.setText("");
	        	pangka.setText("");
	        	pgambar.setText("");
	        	txtlempar.setText("");
	        }
        	break;
        }
    }
}