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Difference of px, dp, dip and sp in Android?
So I know I should use sp only for text font sizes. Now, what I don’t understand is what they do exactly. Let’s say I have the following attribute for a TextView in a layout for a normal screen size:
android:textSize="17dp"
If I replace it with this:
android:textSize="17sp"
What happens? In the visual editor, it doesn’t look any different?
I am guessing that if I have, say a 3.2″ screen which qualifies for the normal size layout, and a 4.0″ screen which also qualifies for my normal size layout, then if I use sp, the text’s size will be slightly scaled up? Is that right?
text rendered with sp is more compatible with accessibility options, for example if the users enables a high contrast mode or universally increases the size of text. Since sp is also density independent, that is the only difference between sp and dp.