title: onMeasure custom view explanation
body: <p>I tried to do custom component. I extended <code>View</code> class and do some drawing in <code>onDraw</code> overrided method. Why I need to override <code>onMeasure</code>? If I didn't, everything seen to be right. May someone explain it? How should I write my <code>onMeasure</code> method? I've seen couple tutorials, but each one is a little bit different than the other. Sometimes they call <code>super.onMeasure</code> at the end, sometimes they use <code>setMeasuredDimension</code> and didn't call it. Where is a difference?</p>
  
  <p>After all I want to use several exactly the same components. I added those components to my <code>XML</code> file, but I don't know how big they should be. I want to set its position and size later (why I need to set size in <code>onMeasure</code> if in <code>onDraw</code> when I draw it, is working as well) in custom component class. When exactly I need to do that?</p>