public class FragmentOne extends Fragment {

    private ViewPager view_pager;
    private ImageView img;
    private WeatherView weather_view;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_fragment_one, container, false);
        view_pager=(ViewPager)view.findViewById(R.id.view_pager);
        weather_view=(WeatherView)view.findViewById(R.id.weather_view);
        img=(ImageView)view.findViewById(R.id.img);

        return view;
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        final RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) img.getLayoutParams();
        weather_view.animal(new WeatherView.AnimalLister() {
            @Override
            public void animal(float f) {
                params.setMargins(0,0,0, (int) f);
                img.setLayoutParams(params);
            }
        });
    }
}

 

public class WeatherView extends View {
    private Path path1,path2;
    private Paint paint1,paint2;
    private float Φ;
    public WeatherView(Context context) {
        super(context);
        init(context);
    }

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

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

    private void init(Context context) {
        paint1 = new Paint();
        paint2 = new Paint();

        paint1.setColor(Color.WHITE);
        paint2.setColor(Color.WHITE);
        paint1.setAntiAlias(true);
        paint2.setAntiAlias(true);
        //paint2.setAlpha(90);

        path1 = new Path();
        path2 = new Path();

    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        path1.reset();
        path2.reset();
        //路徑的起始位置
        path1.moveTo(getLeft(),getBottom());
        path2.moveTo(getLeft(),getBottom());

        double my=Math.PI*2/getWidth();

        Φ-=0.1f;

        //路徑的移動位置
        for(int i=0;i<=getWidth();i+=20){
            path1.lineTo(i, (float) (10*(Math.cos(my*i+Φ))+10));
            path2.lineTo(i, (float) (10*Math.sin(my*i+Φ)));
        }

        //路徑的結束位置
        path1.lineTo(getRight(),getBottom());
        path2.lineTo(getRight(),getBottom());

        canvas.drawPath(path1,paint1);
        canvas.drawPath(path2,paint2);

        postInvalidateDelayed(20);
    }
    private AnimalLister lister;
    public void animal(AnimalLister lister){
        this.lister=lister;
    };
    public interface AnimalLister{
        void animal(float f);
    }
}