Check out example codes for "set layout margin programmatically android". It will help you in understanding the concepts better.

Code Example 1

int sizeInDP = 16;

int marginInDp = (int) TypedValue.applyDimension(
            TypedValue.COMPLEX_UNIT_DIP, sizeInDP, getResources()
                    .getDisplayMetrics());
setMargins(view, sizeInDP, sizeInDP, sizeInDP, sizeInDP);


void setMargins (View view, int left, int top, int right, int bottom) {
  if (view.getLayoutParams() instanceof ViewGroup.MarginLayoutParams) {
    ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) view.getLayoutParams();
    p.setMargins(left, top, right, bottom);
    view.requestLayout();
  }
}

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