Ripple effect on circle stroke

Question

Good Day!

I have circle shape with counter and icon inside.

What is the best practice to add ripple effect on shape border when the stopwatch is running ? Whether ripple is suitable in this case or I must use another approach for example animation? Because one what I found is ripple inside clicked button/view

How to achieve this effect?

Answer 1

RippleBackground is view class in which we are handling ripple effect. Put view into your xml and call start animation from java class.

xml

  <packag.name.RippleBackground
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/content"
        android:visibility="visible"
        app:rb_color="#0099CC"
        app:rb_radius="32dp"
        app:rb_rippleAmount="6"
        app:rb_duration="3000"
        app:rb_scale="6">
    <ImageView
        android:layout_width="64dp"
        android:layout_height="64dp"
        android:layout_centerInParent="true"
        android:id="@+id/centerImage"
        android:src="@drawable/phone1"/>

</packag.name.RippleBackground>

class for animation start

RippleBackground rippleBackground=(RippleBackground)getViewById(R.id.rippleBG);
rippleBackground.startRippleAnimation();

style.xml

<declare-styleable name="RippleBackground">
    <attr name="rb_color" format="color" />
    <attr name="rb_strokeWidth" format="dimension"/>
    <attr name="rb_radius" format="dimension"/>
    <attr name="rb_duration" format="integer"/>
    <attr name="rb_rippleAmount" format="integer"/>
    <attr name="rb_scale" format="float"/>
    <attr name="rb_type" format="enum">
        <enum name="fillRipple" value="0"/>
        <enum name="strokeRipple" value="1"/>
    </attr>
</declare-styleable>

RippleBackground.java

public class RippleBackground extends RelativeLayout{

    private static final int DEFAULT_RIPPLE_COUNT=6;
    private static final int DEFAULT_DURATION_TIME=3000;
    private static final float DEFAULT_SCALE=6.0f;
    private static final int DEFAULT_FILL_TYPE=0;

    private int rippleColor;
    private float rippleStrokeWidth;
    private float rippleRadius;
    private int rippleDurationTime;
    private int rippleAmount;
    private int rippleDelay;
    private float rippleScale;
    private int rippleType;
    private Paint paint;
    private boolean animationRunning=false;
    private AnimatorSet animatorSet;
    private ArrayList<Animator> animatorList;
    private LayoutParams rippleParams;
    private ArrayList<RippleView> rippleViewList=new ArrayList<RippleView>();

    public RippleBackground(Context context) {
        super(context);
    }

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

    public RippleBackground(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs);
    }

    private void init(final Context context, final AttributeSet attrs) {
        if (isInEditMode())
            return;

        if (null == attrs) {
            throw new IllegalArgumentException("Attributes should be provided to this view,");
        }

        final TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RippleBackground);
        rippleColor=typedArray.getColor(R.styleable.RippleBackground_rb_color, getContext().getResources().getColor(R.color.colorAccent));
        rippleStrokeWidth=typedArray.getDimension(R.styleable.RippleBackground_rb_strokeWidth, getResources().getDimension(R.dimen.rippleStrokeWidth));
        rippleRadius=typedArray.getDimension(R.styleable.RippleBackground_rb_radius,getResources().getDimension(R.dimen.rippleRadius));
        rippleDurationTime=typedArray.getInt(R.styleable.RippleBackground_rb_duration,DEFAULT_DURATION_TIME);
        rippleAmount=typedArray.getInt(R.styleable.RippleBackground_rb_rippleAmount,DEFAULT_RIPPLE_COUNT);
        rippleScale=typedArray.getFloat(R.styleable.RippleBackground_rb_scale,DEFAULT_SCALE);
        rippleType=typedArray.getInt(R.styleable.RippleBackground_rb_type,DEFAULT_FILL_TYPE);
        typedArray.recycle();

        rippleDelay=rippleDurationTime/rippleAmount;

        paint = new Paint();
        paint.setAntiAlias(true);
        if(rippleType==DEFAULT_FILL_TYPE){
            rippleStrokeWidth=0;
            paint.setStyle(Paint.Style.FILL);
        }else
            paint.setStyle(Paint.Style.STROKE);
        paint.setColor(rippleColor);

        rippleParams=new LayoutParams((int)(2*(rippleRadius+rippleStrokeWidth)),(int)(2*(rippleRadius+rippleStrokeWidth)));
        rippleParams.addRule(CENTER_IN_PARENT, TRUE);

        animatorSet = new AnimatorSet();
        animatorSet.setInterpolator(new AccelerateDecelerateInterpolator());
        animatorList=new ArrayList<Animator>();

        for(int i=0;i<rippleAmount;i++){
            RippleView rippleView=new RippleView(getContext());
            addView(rippleView,rippleParams);
            rippleViewList.add(rippleView);
             final ObjectAnimator scaleXAnimator = ObjectAnimator.ofFloat(rippleView, "ScaleX", 1.0f, rippleScale);
            scaleXAnimator.setRepeatCount(ObjectAnimator.INFINITE);
            scaleXAnimator.setRepeatMode(ObjectAnimator.RESTART);
            scaleXAnimator.setStartDelay(i * rippleDelay);
            scaleXAnimator.setDuration(rippleDurationTime);
            animatorList.add(scaleXAnimator);
            final ObjectAnimator scaleYAnimator = ObjectAnimator.ofFloat(rippleView, "ScaleY", 1.0f, rippleScale);
            scaleYAnimator.setRepeatCount(ObjectAnimator.INFINITE);
            scaleYAnimator.setRepeatMode(ObjectAnimator.RESTART);
            scaleYAnimator.setStartDelay(i * rippleDelay);
            scaleYAnimator.setDuration(rippleDurationTime);
            animatorList.add(scaleYAnimator);
            final ObjectAnimator alphaAnimator = ObjectAnimator.ofFloat(rippleView, "Alpha", 1.0f, 0f);
            alphaAnimator.setRepeatCount(ObjectAnimator.INFINITE);
            alphaAnimator.setRepeatMode(ObjectAnimator.RESTART);
            alphaAnimator.setStartDelay(i * rippleDelay);
            alphaAnimator.setDuration(rippleDurationTime);
            animatorList.add(alphaAnimator);
        }

        animatorSet.playTogether(animatorList);
    }

    private class RippleView extends View{

        public RippleView(Context context) {
            super(context);
            this.setVisibility(View.INVISIBLE);
        }

        @Override
        protected void onDraw(Canvas canvas) {
            int radius=(Math.min(getWidth(),getHeight()))/2;
            canvas.drawCircle(radius,radius,radius-rippleStrokeWidth,paint);
        }
    }

    public void startRippleAnimation(){
        if(!isRippleAnimationRunning()){
            for(RippleView rippleView:rippleViewList){
                rippleView.setVisibility(VISIBLE);
            }
            animatorSet.start();
            animationRunning=true;
        }
    }

    public void stopRippleAnimation(){
        if(isRippleAnimationRunning()){
            animatorSet.end();
            animationRunning=false;
        }
    }

    public boolean isRippleAnimationRunning(){
        return animationRunning;
    }
}

Note:- You can change RippleBG class according to you requirement and I do not have any reference bcz I wrote this code few year back from some where which I do not remember.