title: Android calculator: Backspace button
body: <p>I have recently designing for an android calculator, and the display is named fakedisplay.
  i am now adding a backspace button for the calculator, and the code is as follows:</p>
  
  <pre><code>    backspace.setOnClickListener(new View.OnClickListener() {        
          @Override 
          public void onClick(View v) { 
  
              clearCalcDisplay = DONT_CLEAR; 
              String str=Fakedisplay.getText().toString();
              if (str.length() &gt;=1 ) { 
                  str = str.substring(0, str.length() - 1);
                  Fakedisplay.setText(str);
                  };
              if (str.length() &lt;1 ) {
                  Fakedisplay.setText("0");
              }
      });   
  </code></pre>
  
  <p>My questions are that </p>
  
  <ol>
  <li><p>I have tried the above and it works for inputs longer than 1 characters, eg 145 it will give out 14, when it is 14 it gives out 1, but when further pressed, the program will be forced-close. Why?</p></li>
  <li><p>And how to consider for decimal input?</p></li>
  </ol>
  
  <p>Would there be any better codes for this function?</p>