اجرای برنامه

package com.cocoder.bang;

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


public class BangActivity extends Activity {

    public int a;


    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final TextView txtcaption = (TextView) findViewById(R.id.txtcaption);
        Button btn = (Button) findViewById(R.id.btn);
        Button btn1 = (Button) findViewById(R.id.btn1);
        Button btn2 = (Button) findViewById(R.id.btn2);
        Button clear = (Button) findViewById(R.id.clear);
        Button btn3 = (Button) findViewById(R.id.btn3);
        final EditText edt = (EditText) findViewById(R.id.edt);
        final EditText edt1 = (EditText) findViewById(R.id.edt1);
        Button btnplus = (Button) findViewById(R.id.btnplus);
        Button btnmanfi = (Button) findViewById(R.id.btnmanfi);
        final DigitalClock ccc = (DigitalClock) findViewById(R.id.ccc);
        Button btntime = (Button) findViewById(R.id.btntime);

        btn.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                String text = edt.getText().toString();
                int intvalue = Integer.parseInt(text);
                String text1 = edt1.getText().toString();
                int intvalue1 = Integer.parseInt(text1);
                txtcaption.setText("" + intvalue * intvalue1);

            }
        });
        btn1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                String text = edt.getText().toString();
                int intvalue = Integer.parseInt(text);
                String text1 = edt1.getText().toString();
                int intvalue1 = Integer.parseInt(text1);
                txtcaption.setText("" + (intvalue + intvalue1));

            }
        });
        btn2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                String text = edt.getText().toString();
                int intvalue = Integer.parseInt(text);
                String text1 = edt1.getText().toString();
                int intvalue1 = Integer.parseInt(text1);
                txtcaption.setText("" + (intvalue - intvalue1));

            }
        });
        btn3.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                String text = edt.getText().toString();
                int intvalue = Integer.parseInt(text);
                String text1 = edt1.getText().toString();
                int intvalue1 = Integer.parseInt(text1);
                txtcaption.setText("" + (intvalue / intvalue1));

            }
        });
        clear.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                txtcaption.setText("");

            }
        });

        btnplus.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                a++;

                txtcaption.setText("" + a);

            }
        });
        btnmanfi.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                a--;

                txtcaption.setText("" + a);

            }
        });
        ccc.setVisibility(View.GONE);
        btntime.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                int visibility = ccc.getVisibility();
                boolean check = (visibility == View.INVISIBLE);
                if (check)
                {
                    ccc.setVisibility(View.GONE);
                }

                else {
                    ccc.setVisibility(View.VISIBLE);

                }

            }
        });
    }
}