resultless android app..calculator always gives 0
<p>I develop an application where spinner contains add, sub, mul &amp; div... but the result always gives zero. How I develop the app when button clicked the calculation solved depends upon the selected value of the spinner. The code is below::</p>

<pre><code>public void Select(View view)
    {
        TextView txt1=(TextView)findViewById(R.id.editText1);
        TextView txt2=(TextView)findViewById(R.id.editText2);

        int x=Integer.parseInt(txt1.getText().toString());
        int y=Integer.parseInt(txt2.getText().toString());

        Spinner spin1=(Spinner)findViewById(R.id.spinner1);
        String spin_value= spin1.getItemAtPosition(spin1.getSelectedItemPosition()).toString();

        if(spin_value=="Add")
        {
            int z=x+y;
            String addvalue=String.valueOf(z);
            Toast.makeText(this, addvalue, Toast.LENGTH_LONG).show();
        }
        else if (spin_value=="Sub") 
        {
            int p=x-y;
            String subvalue=String.valueOf(p);
            Toast.makeText(this, subvalue, Toast.LENGTH_LONG).show();
        }
        else if (spin_value=="Mul") 
        {
            int k=x*y;
            String mulvalue=String.valueOf(k);
            Toast.makeText(this, mulvalue, Toast.LENGTH_LONG).show();
        }
        else
        {
            int g=x/y;
            String divvalue=String.valueOf(g);
            Toast.makeText(this, divvalue, Toast.LENGTH_LONG).show();
        }
    }
}   
</code></pre>
