Android自定义动画系列十五，今天来分享第15个自定义动画，一个跳动的音符动画（MUSIC_PATH）。
原文链接：查看原文
介绍
废话不多说，先看看效果吧，如下：
系列十五
正文
今天又有一个新灵感，新增了一个小动画跳动的音符，希望大家可以喜欢。
希望大家可以多多留言，多多建议，多多评论。可以在任何地方。如果想让我能够看见，还是希望在 Github：zyao89/ZCustomView 项目里，或者 我的个人网站博客 里进行留言。
使用方式与以往一致，可参考Android自定义加载动画库zLoading
部分代码如下：
/**
* Created by zyao89 on 2018/3/11.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: https://zyao89.cn
*/
public class MusicPathBuilder extends BaseStateBuilder
{
private final int MUSIC_LINE_COUNT = 5;
private Paint mPaint;
private float mR;
private LinkedList<Path> mMusicPaths;
private LinkedList<Path> mMusicDrawPaths;
private PathMeasure mPathMeasure;
private LinkedList<MusicParam> mMusicParams;
private boolean mOpenJump = false;
private DecelerateInterpolator mDecelerateInterpolator;
private BounceInterpolator mBounceInterpolator;
@Override
protected int getStateCount()
{
return 3;
}
@Override
protected void initParams(Context context, Paint paint)
{
mPaint = paint;
mPaint.setStrokeWidth(2);
mR = getAllSize();
initPaths();
initPathMeasure();
initMusicParams();
initInterpolator();
}
private void initPaths()
{
mMusicPaths = new LinkedList<Path>();
// 线长
float lineW = mR * 2;
// 线间距
float space = mR * 2 / MUSIC_LINE_COUNT;
// 起点
float startXP = getViewCenterX() - mR;
float startYP = getViewCenterY() + mR;
// 五线谱
for (int i = 0; i < MUSIC_LINE_COUNT; I++)
{
Path path = new Path();
path.moveTo(startXP, startYP - (i * space));
path.lineTo(startXP + lineW, startYP - (i * space));
mMusicPaths.add(path);
}
}
private void initPathMeasure()
{
mMusicDrawPaths = new LinkedList<>();
// 五线谱
for (int i = 0; i < MUSIC_LINE_COUNT; I++)
{
Path drawPath = new Path();
mMusicDrawPaths.add(drawPath);
}
mPathMeasure = new PathMeasure();
}
private void initMusicParams()
{
float musicWidth = mR * 0.2f;
float musicHeight = mR;
mMusicParams = new LinkedList<>();
float musicPointHeight = mR * 2 / MUSIC_LINE_COUNT;
float left = getViewCenterX() - musicWidth / 2;
float right = getViewCenterX() + musicWidth / 2;
float top = getViewCenterY() + musicHeight - musicPointHeight * 1.5f;
float bottom = getViewCenterY() + musicHeight - musicPointHeight * 0.5f;
RectF rectF = new RectF(left - mR * 0.5f, top, right - mR * 0.5f, bottom);
float offsetX = (float) (musicWidth * 0.5 * Math.cos(75));
PointF sPointF = new PointF(rectF.right + offsetX, rectF.centerY());
PointF ePointF = new PointF(rectF.right + offsetX, rectF.centerY() - musicHeight);
MusicParam musicParam = new MusicParam(rectF, sPointF, ePointF);
mMusicParams.add(musicParam);
rectF = new RectF(left + mR * 0.5f, top - musicPointHeight, right + mR * 0.5f, bottom - musicPointHeight);
offsetX = (float) (musicWidth * 0.5 * Math.cos(75));
sPointF = new PointF(rectF.right + offsetX, rectF.centerY());
ePointF = new PointF(rectF.right + offsetX, rectF.centerY() - musicHeight);
musicParam = new MusicParam(rectF, sPointF, ePointF);
mMusicParams.add(musicParam);
}
private void initInterpolator()
{
mDecelerateInterpolator = new DecelerateInterpolator();
mBounceInterpolator = new BounceInterpolator();
}
@Override
protected void onComputeUpdateValue(ValueAnimator animation, float animatedValue, int state)
{
switch (state)
{
case 0:
animation.setInterpolator(mDecelerateInterpolator);
resetDrawPath();
for (int i = 0; i < MUSIC_LINE_COUNT; I++)
{
mPathMeasure.setPath(mMusicPaths.get(i), false);
if (i % 2 == 0)
{
float stop = mPathMeasure.getLength() * animatedValue;
float start = (float) (stop - ((0.5 - Math.abs(animatedValue - 0.5)) * 200f));
mPathMeasure.getSegment(start, stop, mMusicDrawPaths.get(i), true);
}
else
{
float stop = mPathMeasure.getLength() * (1 - animatedValue);
float start = (float) (stop - ((0.5 - Math.abs((1 - animatedValue) - 0.5)) * 200f));
mPathMeasure.getSegment(start, stop, mMusicDrawPaths.get(i), true);
}
}
break;
case 1:
resetDrawPath();
for (int i = 0; i < MUSIC_LINE_COUNT; I++)
{
mPathMeasure.setPath(mMusicPaths.get(i), false);
if (i % 2 == 0)
{
float stop = mPathMeasure.getLength() * animatedValue;
float start = 0;
mPathMeasure.getSegment(start, stop, mMusicDrawPaths.get(i), true);
}
else
{
float stop = mPathMeasure.getLength();
float start = mPathMeasure.getLength() * (1 - animatedValue);
mPathMeasure.getSegment(start, stop, mMusicDrawPaths.get(i), true);
}
}
break;
case 2:
animation.setInterpolator(mBounceInterpolator);
// jump
mOpenJump = true;
// 线间距
float space = mR * 2 / MUSIC_LINE_COUNT;
for (int i = 0; i < mMusicParams.size(); I++)
{
MusicParam musicParam = mMusicParams.get(i);
if (i % 2 == 0)
{
musicParam.setOffsetY(animatedValue * space);
}
else
{
musicParam.setOffsetY((1 - animatedValue) * space);
}
}
break;
case 3:
// jump
mOpenJump = true;
// 线间距
space = mR * 2 / MUSIC_LINE_COUNT;
for (int i = 0; i < mMusicParams.size(); I++)
{
MusicParam musicParam = mMusicParams.get(i);
if (i % 2 == 0)
{
musicParam.setOffsetY((1 - animatedValue) * space);
}
else
{
musicParam.setOffsetY(animatedValue * space);
}
}
break;
default:
break;
}
}
@Override
protected void onDraw(Canvas canvas)
{
for (Path drawPath : mMusicDrawPaths)
{
canvas.drawPath(drawPath, mPaint);
}
if (mOpenJump)
{
drawMusic(canvas);
}
}
private void drawMusic(Canvas canvas)
{
for (MusicParam musicParam : mMusicParams)
{
mPaint.setStrokeWidth(4);
canvas.save();
RectF oldCircleRectF = musicParam.getCircleRectF();
RectF circleRectF = new RectF(oldCircleRectF);
float offsetY = musicParam.getOffsetY();
circleRectF.set(oldCircleRectF.left, oldCircleRectF.top - offsetY, oldCircleRectF.right, oldCircleRectF.bottom - offsetY);
canvas.rotate(75, circleRectF.centerX(), circleRectF.centerY());
mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
canvas.drawOval(circleRectF, mPaint);
mPaint.setStyle(Paint.Style.STROKE);
canvas.restore();
PointF startPointF = musicParam.getLineStartPointF();
PointF endPointF = musicParam.getLineEndPointF();
canvas.drawLine(startPointF.x, startPointF.y - offsetY, endPointF.x, endPointF.y - offsetY, mPaint);
mPaint.setStrokeWidth(2);
}
}
private void resetDrawPath()
{
mOpenJump = false;
for (Path path : mMusicDrawPaths)
{
path.reset();
path.lineTo(0, 0);
}
for (MusicParam musicParam : mMusicParams)
{
musicParam.clear();
}
}
static class MusicParam
{
private final RectF mCircleRectF;
private final PointF mLineStartPointF;
private final PointF mLineEndPointF;
private float mOffsetY = 0;
MusicParam(RectF rectF, PointF sPointF, PointF ePointF)
{
mCircleRectF = rectF;
mLineStartPointF = sPointF;
mLineEndPointF = ePointF;
}
RectF getCircleRectF()
{
return mCircleRectF;
}
PointF getLineStartPointF()
{
return mLineStartPointF;
}
PointF getLineEndPointF()
{
return mLineEndPointF;
}
float getOffsetY()
{
return mOffsetY;
}
void setOffsetY(float v)
{
mOffsetY = v;
}
void clear()
{
mOffsetY = 0;
}
}
}
注释很少，请见谅我的懒。
总结
小伙伴们，要是想看更多细节，可以前往文章最下面的Github链接，如果大家觉得ok的话，希望能给个喜欢，最渴望的是在Github上给个star。谢谢了。
如果大家有什么更好的方案，或者想要实现的加载效果，可以给我留言或者私信我，我会想办法实现出来给大家。谢谢支持。
Github：zyao89/ZCustomView
作者：Zyao89；转载请保留此行，谢谢；
个人博客：https://zyao89.cn
