Question

Is there any way to figure out how many pixels wide a certain String in a certain Font is?

In my Activity, there are dynamic Strings put on a Button. Sometimes, the String is too long and it’s divided on two lines, what makes the Button look ugly. However, as I don’t use a sort of a console Font, the single char-widths may vary. So it’s not a help writing something like

String test = "someString";
if(someString.length()>/*someValue*/){
    // decrement Font size
}

because an “mmmmmmmm” is wider than “iiiiiiii”.

Alternatively, is there a way in Android to fit a certain String on a single line, so the system “scales” the Font size automatically?

EDIT:

since the answer from wsanville was really nice, here’s my code setting the font size dynamically:

private void setupButton(){
    Button button = new Button();
    button.setText(getButtonText()); // getButtonText() is a custom method which returns me a certain String
    Paint paint = button.getPaint();
    float t = 0;
    if(paint.measureText(button.getText().toString())>323.0){ //323.0 is the max width fitting in the button
    t = getAppropriateTextSize(button);
    button.setTextSize(t);
    }
}

private float getAppropriateTextSize(Button button){
    float textSize = 0;
    Paint paint = button.getPaint();
    textSize = paint.getTextSize();
    while(paint.measureText(button.getText().toString())>323.0){
        textSize -= 0.25;
        button.setTextSize(textSize);
    }
    return textSize;
}

Answer 1

You should be able to use Paint.setTypeface() and then Paint.measureText(). You’ll find other methods on the Paint class like setTextSize() to help too.

Your followup question about scaling text was addressed in this question.