Animates an Integer in a Textview incrementally or decreamentaly using ObjectAnimator class.

IntegerTextviewAnimator.java

import android.animation.ObjectAnimator;
import android.animation.TypeEvaluator;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.util.Property;
import android.widget.TextView;

/**
 * Created by Hossein Moradgholi (h.moradgholi[-AT-]icloud.com) on 1/14/15 AD.
 */
public class IntegerTextviewAnimator extends TextView {

    private int DEFAULT_TIME_COHESION = 100;
    public IntegerTextviewAnimator(Context context) {
        super(context);
    }

    public IntegerTextviewAnimator(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public IntegerTextviewAnimator(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public void animateValueTo(int value){
        int currentValue = Integer.parseInt(getText().toString());
        if (currentValue == value) return;
        
        // Type evaluator for linear interpolation
        TypeEvaluator<CharSequence> charSequenceTypeEvaluator = new TypeEvaluator<CharSequence>() {
            @Override
            public CharSequence evaluate(float fraction, CharSequence start, CharSequence end) {
                int startValue = Integer.parseInt(start.toString());
                int endValue = Integer.parseInt(end.toString());
                int value = (int)((endValue - startValue) * fraction) + startValue;
                return Integer.toString(value);
            }
        };
        
        // we need to animate 'text' attribute
        Property<TextviewAnimator, CharSequence> textViewStringProperty = Property.of(TextviewAnimator.class, CharSequence.class, "text");
    
        CharSequence charSequence = Integer.toString(value);
        final ObjectAnimator objectAnimator = ObjectAnimator.ofObject(this, textViewStringProperty, charSequenceTypeEvaluator, charSequence);
        
        // animation duration
        int animationDuration = Math.abs(currentValue - value) * DEFAULT_TIME_COHESION;
        objectAnimator.setDuration(animationDuration);
        
        objectAnimator.start();
    }
}