引导页

public class MainActivity extends AppCompatActivity {

    MyView my_View;
    private ValueAnimator animator;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    my_View=findViewById(R.id.my_View);
    indata();
    animator.addListener(new Animator.AnimatorListener() {
        @Override
        public void onAnimationStart(Animator animation) {

        }

        @Override
        public void onAnimationEnd(Animator animation) {
            Intent intent = new Intent(MainActivity.this,ShowActivity.class);
            startActivity(intent);
            finish();
        }

        @Override
        public void onAnimationCancel(Animator animation) {

        }

        @Override
        public void onAnimationRepeat(Animator animation) {

        }
    });
}

private void indata() {

    animator = new ValueAnimator();
    animator.setDuration(5000);
    animator.setObjectValues(new PointF(1,1));
    animator.setInterpolator(new LinearInterpolator());
    animator.setEvaluator(new TypeEvaluator() {
        @Override
        public Object evaluate(float v, Object startValue, Object endValue) {
            PointF pointF = new PointF();
            pointF.x=v*200*3;
            pointF.y=0.56f*200*(3*v)*(3*v);
            return pointF;
        }
    });
    animator.start();
    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            PointF pointF = (PointF) animation.getAnimatedValue();
            my_View.setX(pointF.x);
            my_View.setY(pointF.y);
        }
    });
}

public class MyView extends View {
int w=20;
public MyView(Context context) {
super(context);
}

public MyView(Context context, @Nullable AttributeSet attrs) {
    super(context, attrs);
}

public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
}

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    Paint paint = new Paint();
    paint.setColor(Color.BLUE);
    paint.setAntiAlias(true);
    paint.setStyle(Paint.Style.FILL);
    paint.setStrokeWidth(w);
    RectF rectF = new RectF(5,5,100,100);
    canvas.drawArc(rectF,360,360,false,paint);
}