MainActivity.java

package ir.apdroid.calc; 
 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.EditText; 
import android.widget.TextView; 
import android.widget.Toast; 
 
public class MainActivity extends AppCompatActivity { 
 
    EditText n1,n2; 
    TextView result; 
 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState); 
        setContentView(R.layout.activity_main); 
 
        init(); 
    } 
 
    public void init(){ 
        n1=(EditText)findViewById(R.id.editText1); 
        n2=(EditText)findViewById(R.id.editText2); 
        result=(TextView)findViewById(R.id.textView3); 
    } 
 
 
    public void add(View v){ 
        try { 
            int x = Integer.parseInt(n1.getText().toString()); 
            int y = Integer.parseInt(n2.getText().toString()); 
            int z = x + y; 
            result.setText(String.valueOf(z)); 
        } 
        catch(Exception e){ 
            Toast.makeText(this, "خطا در اعداد ورودی "+"\n"+e , Toast.LENGTH_LONG).show(); 
        } 
    } 
 
}