Issue reading String
<p>I have an issue with my basic addition program everything works such as typing the value and testing if its not wrong but an issue occurs when i open my program and leave the TextView blank and press button check , the program terminates.<br>
Ive tried convert String =""; to an integer but then my program does not start.<br>
I belive it only compares integers and not String but im unsure how to overcome it<br>
Any help would be appreciated.</p>

<pre><code>int one=1, two=2;
ans = one + two;
TextView = Value;
TextView = i;

Button one,check;

i = (TextView) findViewById(R.id.display);
Value = (TextView) findViewById(R.id.answer);

one= (Button) findViewById(R.id.one);
one.setOnClickListener(this);

check= (Button) findViewById(R.id.check);
check.setOnClickListener(this);


        public void onClick(View v) {

        switch(v.getId()){  


        case R.id.one:
            ans.append("1");
            break;

        case R.id.check:

        if (answer ==(Integer.parseInt(Value.getText().toString())))
            {

             display.setText(one+"+"+two);
             ans.setText("");

            }

           else
               {
           i.setText("Invalid");
               }

            break;
}
}
</code></pre>
