Simple calculator , Dialog Activity , Android

plus_minus_first_app

package com.example.first;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EdgeEffect;
import android.widget.EditText;
import android.widget.Toast;


public class MainActivity extends Activity {
	
	int one,two,flag,result;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        
    Button plus=(Button)findViewById(R.id.plus_but);
    Button minus=(Button)findViewById(R.id.min_but);
    Button darb=(Button)findViewById(R.id.darb_but);
    Button qisma=(Button)findViewById(R.id.qisma_but);
    Button equal=(Button)findViewById(R.id.equal_but);
    final EditText text=(EditText)findViewById(R.id.text1);
    
    
   
   
   
    plus.setOnClickListener(new View.OnClickListener() {
		
		@Override
		public void onClick(View arg0) {
			one = Integer.parseInt(text.getText().toString());
			flag=1;
			text.setText("");
			
		}
	} );
    
    minus.setOnClickListener(new View.OnClickListener() {
    	@Override
    	public void onClick(View arg0) {
    		one = Integer.parseInt(text.getText().toString());
			flag=2;
			text.setText("");
    	}
    });
    
    
    darb.setOnClickListener(new View.OnClickListener() {
    	@Override
    	public void onClick(View arg0) {
    		one = Integer.parseInt(text.getText().toString());
			flag=3;
			text.setText("");
    	}
    });
    
    qisma.setOnClickListener(new View.OnClickListener() {
    	@Override
    	public void onClick(View arg0) {
    		one = Integer.parseInt(text.getText().toString());
			flag=4;
			text.setText("");
    	}
    });
    equal.setOnClickListener(new View.OnClickListener() {
    	
    	@Override
    	public void onClick(View arg0) {
            two = Integer.parseInt(text.getText().toString());
			
    		if (flag==1){
    			
    			result=one+two;
    			Toast.makeText(MainActivity.this, "The result is : "+result, Toast.LENGTH_LONG).show();
                text.setText(""); 
                one=0;
                two=0;
    		}else if(flag==2){
    			
    			result=one-two;
    			Toast.makeText(MainActivity.this, "The result is : "+result, Toast.LENGTH_LONG).show();
    			text.setText("");
    			one=0;
    			two=0;
    		}else if(flag==3){
    			result=one*two;
    			Toast.makeText(MainActivity.this, "The result is : "+result, Toast.LENGTH_LONG).show();
                text.setText(""); 
                one=0;
                two=0;
    		}else if(flag==4){
    			if(two==0){
    				Toast.makeText(MainActivity.this, "Can't Combine", Toast.LENGTH_LONG).show();
                    text.setText(""); 
                    one=0;
                    two=0;
    			}else {
    			result=one/two;
    			Toast.makeText(MainActivity.this, "The result is : "+result, Toast.LENGTH_LONG).show();
                text.setText(""); 
                one=0;
                two=0;}
    		}
    		
    	}
    });
    
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    
}