Android加载动画系列——PlayBallLoadingAnim

Android加载动画系列——PlayBallLoadingAnim

PlayBallLoadingAnim是一款小球弹跳动画，很像小时玩过得弹簧床。

       让我们先来看看效果图：

1、PlayBallLoadingAnim.java源码如下：

public class PlayBallLoadingAnim extends View {    private Paint mPaint, mPaintCircle, mPaintBall;    private float mPaintStrokeWidth;    private float mHeight = 0f;    private float mWidth = 0f;    private float quadToStart = 0f;    private float mRadius = 0f;    private float mRadiusBall = 0f;    private float ballY = 0f;    Path path = new Path();    public PlayBallLoadingAnim(Context context) {        this(context, null);    }    public PlayBallLoadingAnim(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public PlayBallLoadingAnim(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        initPaint();    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        super.onMeasure(widthMeasureSpec, heightMeasureSpec);        mHeight = getMeasuredHeight();        mWidth = getMeasuredWidth();        quadToStart = mHeight / 2;        mRadius = dip2px(3);        mPaintStrokeWidth = 2;        ballY = mHeight / 2;        mRadiusBall = dip2px(4);    }    public int dip2px(float dpValue) {        final float scale = getContext().getResources().getDisplayMetrics().density;        return (int) (dpValue * scale + 0.5f);    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        path = new Path();        path.moveTo(0 + mRadius * 2 + mPaintStrokeWidth, getMeasuredHeight() / 2);        path.quadTo(mWidth / 2, quadToStart, mWidth - mRadius * 2 - mPaintStrokeWidth, mHeight / 2);        mPaint.setStrokeWidth(2);        canvas.drawPath(path, mPaint);        mPaintCircle.setStrokeWidth(mPaintStrokeWidth);        canvas.drawCircle(mRadius + mPaintStrokeWidth, mHeight / 2, mRadius, mPaintCircle);        canvas.drawCircle(mWidth - mRadius - mPaintStrokeWidth, mHeight / 2, mRadius, mPaintCircle);        if (ballY - mRadiusBall > mRadiusBall) {            canvas.drawCircle(mWidth / 2, ballY - mRadiusBall, mRadiusBall, mPaintBall);        } else {            canvas.drawCircle(mWidth / 2, mRadiusBall, mRadiusBall, mPaintBall);        }    }    private void initPaint() {        mPaint = new Paint();        mPaint.setAntiAlias(true);        mPaint.setStyle(Paint.Style.STROKE);        mPaint.setColor(Color.WHITE);        mPaintCircle = new Paint();        mPaintCircle.setAntiAlias(true);        mPaintCircle.setStyle(Paint.Style.STROKE);        mPaintCircle.setColor(Color.WHITE);        mPaintBall = new Paint();        mPaintBall.setAntiAlias(true);        mPaintBall.setStyle(Paint.Style.FILL);        mPaintBall.setColor(Color.WHITE);    }    ValueAnimator valueAnimator = null;    public void stopAnim() {        if (valueAnimator != null) {            clearAnimation();            quadToStart = mHeight / 2;            ballY = mHeight / 2;            valueAnimator.setRepeatCount(0);            valueAnimator.cancel();            valueAnimator.end();        }    }    private ValueAnimator startViewAnim(float startF, final float endF, long time) {        valueAnimator = ValueAnimator.ofFloat(startF, endF);        valueAnimator.setDuration(time);        valueAnimator.setInterpolator(new LinearInterpolator());        valueAnimator.setRepeatCount(ValueAnimator.INFINITE);        valueAnimator.setRepeatMode(ValueAnimator.REVERSE);        valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {            @Override            public void onAnimationUpdate(ValueAnimator animation) {                float value = (float) valueAnimator.getAnimatedValue();                if (value > 0.75) {                    quadToStart = mHeight / 2 - (1f - (float) valueAnimator.getAnimatedValue()) * mHeight / 3f;                } else {                    quadToStart = mHeight / 2 + (1f - (float) valueAnimator.getAnimatedValue()) * mHeight / 3f;                }                if (value > 0.35f) {                    ballY = mHeight / 2 - (mHeight / 2 * value);                } else {                    ballY = mHeight / 2 + (mHeight / 6 * value);                }                invalidate();            }        });        valueAnimator.addListener(new AnimatorListenerAdapter() {            @Override            public void onAnimationEnd(Animator animation) {                super.onAnimationEnd(animation);            }        });        if (!valueAnimator.isRunning()) {            valueAnimator.start();        }        return valueAnimator;    }    public void startAnim() {        stopAnim();        startViewAnim(0f, 1f, 800);    }}

 

2、接下来我们在layout中引用自定义的动画控件，如下所示：

<com.cyril.loadinganim.PlayBallLoadingAnim    android:id="@+id/playball"    android:layout_width="50dp"    android:layout_height="50dp"     />

 

3、然后在Activity中实现动画的播放和停止，使用事例如下：

playBallLoadingAnim = (PlayBallLoadingAnim) findViewById(R.id.playball);playBallLoadingAnim.startAnim();

4、  戳这里，小编带你去源码的下载地址：http://download.csdn.net/detail/zhimingshangyan/9582830