How to assign text size in sp value using java code

Question

If I assign an integer value to change a certain text size of a TextView using java code, the value is interpreted as pixel (px).

Now does

Answer 1

Based on the the source code of setTextSize:

public void setTextSize(int unit, float size) {
    Context c = getContext();
    Resources r;

    if (c == null)
        r = Resources.getSystem();
    else
        r = c.getResources();

    setRawTextSize(TypedValue.applyDimension(
        unit, size, r.getDisplayMetrics()));
}

I build this function for calulating any demension to pixels:

int getPixels(int unit, float size) {
    DisplayMetrics metrics = Resources.getSystem().getDisplayMetrics();
    return (int)TypedValue.applyDimension(unit, size, metrics);
}

Where unit is something like TypedValue.COMPLEX_UNIT_SP.

Answer 2

Thanks @John Leehey and @PeterH:

desiredSp = getResources().getDimension(R.dimen.desired_sp);
density = getResources().getDisplayMetrics().density;
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, desiredSp / density);

The thing is if you define R.dimen.desired_sp to 25 in your dimen.xml

1. On non-HD Device: desiredSp is still 25, density = 1
2. On HD Device(like Nexus 7 2nd Generation): desiredSp becomes 50 ish, density = 2

Answer 3

semeTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, 
                       context.getResources().getDimension(R.dimen.text_size_in_dp))

Answer 4

From Api level 1, you can use the public void setTextSize (float size) method.

From the documentation:

Set the default text size to the given value, interpreted as "scaled pixel" units. This size is adjusted based on the current density and user font size preference.

Parameters: size -> float: The scaled pixel size.

So you can simple do:

textView.setTextSize(12); // your size in sp

Answer 5

When the accepted answer doesn't work (for example when dealing with Paint) you can use:

float spTextSize = 12;
float textSize = spTextSize * getResources().getDisplayMetrics().scaledDensity;
textPaint.setTextSize(textSize);

Answer 6

After trying all the solutions and none giving acceptable results (maybe because I was working on a device with default very large fonts), the following worked for me (COMPLEX_UNIT_DIP = Device Independent Pixels):

textView.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 14);