How to format numbers on Android
<p>i am learning to program mobile aplications on Android. My first app is a unit converter. Everithing is working for now, but i have a question about formating numbers. I hava this code to get text from buttons and to convert the appropriet output: </p>

<pre><code>if (bPrevodZ.getText() == "milimeter"){
    if (bPrevodDo.getText()=="kilometer"){
        String PomocnaPremenna = jednotkaZ.getText().toString();
        double cisloNaPrevod = Double.parseDouble(PomocnaPremenna);
        cisloNaPrevod = cisloNaPrevod*0.0000001;
        vysledok.setText(Double.toString(cisloNaPrevod));
    }
</code></pre>

<p>The final result is "cisloNaPrevod", but i have problems to show a good format of that number. For example: 
12345 mm = 0,0012345 km this is good right ? :)</p>

<p>but if i convert:
563287 mm = 0.05632869999999995  this is bad :) i need it to show 0.0563287</p>

<p>Thx for any help</p>
