Question

Is it possible to reduce the AlertDialog.Builder title font size and positive button size? If yes, Just let me how to do?

Answer 1

About font size you can use this:

SpannableStringBuilder ssBuilser = new SpannableStringBuilder("Sample");
StyleSpan span = new StyleSpan(Typeface.ITALIC);
ScaleXSpan span1 = new ScaleXSpan(1);
ssBuilser.setSpan(span, 0, 5, Spanned.SPAN_INCLUSIVE_INCLUSIVE);
ssBuilser.setSpan(span1, 0, 5, Spanned.SPAN_INCLUSIVE_INCLUSIVE);

AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);

builder.setTitle(ssBuilser);

builder.show();

Also You can set custom title:

float size = 25;    

AlertDialog.Builder builder = new AlertDialog.Builder(this);    
final TextView myView = new TextView(getApplicationContext());
myView.setText("A Sample Title to Change Dialog Title");
myView.setTextSize(size);
builder.setCustomTitle(myView);