Android仿QQ聊天撒花特效 很真实

2019-12-10 18:03:24于丽

3.FllowerAnimation

动画类

package com.lgl.test;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import android.animation.ObjectAnimator;
import android.animation.ValueAnimator;
import android.animation.ValueAnimator.AnimatorUpdateListener;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PathMeasure;
import android.util.Log;
import android.util.TypedValue;
import android.view.View;
import android.view.WindowManager;
import android.view.animation.AccelerateInterpolator;

/**
 * 撒花 用到的知识点: 1、android属性动画 2、Path路径绘制 3、贝塞尔曲线
 */
public class FllowerAnimation extends View implements AnimatorUpdateListener {

 /**
 * 动画改变的属性值
 */
 private float phase1 = 0f;
 private float phase2 = 0f;
 private float phase3 = 0f;

 /**
 * 小球集合
 */
 private List<Fllower> fllowers1 = new ArrayList<Fllower>();
 private List<Fllower> fllowers2 = new ArrayList<Fllower>();
 private List<Fllower> fllowers3 = new ArrayList<Fllower>();

 /**
 * 动画播放的时间
 */
 private int time = 4000;
 /**
 * 动画间隔
 */
 private int delay = 400;

 int[] ylocations = { -100, -50, -25, 0 };

 /**
 * 资源ID
 */
 // private int resId = R.drawable.fllower_love;
 public FllowerAnimation(Context context) {
 super(context);
 init(context);
 // this.resId = resId;
 }

 @SuppressWarnings("deprecation")
 private void init(Context context) {
 WindowManager wm = (WindowManager) context
  .getSystemService(Context.WINDOW_SERVICE);
 width = wm.getDefaultDisplay().getWidth();
 height = (int) (wm.getDefaultDisplay().getHeight() * 3 / 2f);

 mPaint = new Paint();
 mPaint.setAntiAlias(true);
 // mPaint.setStrokeWidth(2);
 // mPaint.setColor(Color.BLUE);
 // mPaint.setStyle(Style.STROKE);

 pathMeasure = new PathMeasure();

 builderFollower(fllowerCount, fllowers1);
 builderFollower(fllowerCount, fllowers2);
 builderFollower(fllowerCount, fllowers3);

 }

 /**
 * 宽度
 */
 private int width = 0;
 /**
 * 高度
 */
 private int height = 0;

 /**
 * 曲线高度个数分割
 */
 private int quadCount = 10;
 /**
 * 曲度
 */
 private float intensity = 0.2f;

 /**
 * 第一批个数
 */
 private int fllowerCount = 4;

 /**
 * 创建花
 */
 private void builderFollower(int count, List<Fllower> fllowers) {

 int max = (int) (width * 3 / 4f);
 int min = (int) (width / 4f);
 Random random = new Random();
 for (int i = 0; i < count; i++) {
  int s = random.nextInt(max) % (max - min + 1) + min;
  Path path = new Path();
  CPoint CPoint = new CPoint(s, ylocations[random.nextInt(3)]);
  List<CPoint> points = builderPath(CPoint);
  drawFllowerPath(path, points);
  Fllower fllower = new Fllower();
  fllower.setPath(path);
  Bitmap bitmap = BitmapFactory.decodeResource(getResources(),
   R.drawable.lift_flower);
  fllower.setResId(bitmap);
  fllowers.add(fllower);
 }

 }

 /**
 * 画曲线
 *
 * @param path
 * @param points
 */
 private void drawFllowerPath(Path path, List<CPoint> points) {
 if (points.size() > 1) {
  for (int j = 0; j < points.size(); j++) {

  CPoint point = points.get(j);

  if (j == 0) {
   CPoint next = points.get(j + 1);
   point.dx = ((next.x - point.x) * intensity);
   point.dy = ((next.y - point.y) * intensity);
  } else if (j == points.size() - 1) {
   CPoint prev = points.get(j - 1);
   point.dx = ((point.x - prev.x) * intensity);
   point.dy = ((point.y - prev.y) * intensity);
  } else {
   CPoint next = points.get(j + 1);
   CPoint prev = points.get(j - 1);
   point.dx = ((next.x - prev.x) * intensity);
   point.dy = ((next.y - prev.y) * intensity);
  }

  // create the cubic-spline path
  if (j == 0) {
   path.moveTo(point.x, point.y);
  } else {
   CPoint prev = points.get(j - 1);
   path.cubicTo(prev.x + prev.dx, (prev.y + prev.dy), point.x
    - point.dx, (point.y - point.dy), point.x, point.y);
  }
  }
 }
 }

 /**
 * 曲线摇摆的幅度
 */
 private int range = (int) TypedValue
  .applyDimension(TypedValue.COMPLEX_UNIT_DIP, 70, getResources()
   .getDisplayMetrics());

 /**
 * 画路径
 *
 * @param point
 * @return
 */
 private List<CPoint> builderPath(CPoint point) {
 List<CPoint> points = new ArrayList<CPoint>();
 Random random = new Random();
 for (int i = 0; i < quadCount; i++) {
  if (i == 0) {
  points.add(point);
  } else {
  CPoint tmp = new CPoint(0, 0);
  if (random.nextInt(100) % 2 == 0) {
   tmp.x = point.x + random.nextInt(range);
  } else {
   tmp.x = point.x - random.nextInt(range);
  }
  tmp.y = (int) (height / (float) quadCount * i);
  points.add(tmp);
  }
 }
 return points;
 }

 /**
 * 画笔
 */
 private Paint mPaint;

 /**
 * 测量路径的坐标位置
 */
 private PathMeasure pathMeasure = null;

 @Override
 protected void onDraw(Canvas canvas) {
 super.onDraw(canvas);

 drawFllower(canvas, fllowers1);
 drawFllower(canvas, fllowers2);
 drawFllower(canvas, fllowers3);

 }

 /**
 * 高度往上偏移量,把开始点移出屏幕顶部
 */
 private float dy = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
  40, getResources().getDisplayMetrics());

 /**
 * @param canvas
 * @param fllowers
 */
 private void drawFllower(Canvas canvas, List<Fllower> fllowers) {
 for (Fllower fllower : fllowers) {
  float[] pos = new float[2];
  // canvas.drawPath(fllower.getPath(),mPaint);
  pathMeasure.setPath(fllower.getPath(), false);
  pathMeasure.getPosTan(height * fllower.getValue(), pos, null);
  // canvas.drawCircle(pos[0], pos[1], 10, mPaint);
  canvas.drawBitmap(fllower.getResId(), pos[0], pos[1] - dy, null);
 }
 }

 ObjectAnimator mAnimator1;
 ObjectAnimator mAnimator2;
 ObjectAnimator mAnimator3;

 public void startAnimation() {
 if (mAnimator1 != null && mAnimator1.isRunning()) {
  mAnimator1.cancel();
 }
 mAnimator1 = ObjectAnimator.ofFloat(this, "phase1", 0f, 1f);
 mAnimator1.setDuration(time);
 mAnimator1.addUpdateListener(this);

 mAnimator1.start();
 mAnimator1.setInterpolator(new AccelerateInterpolator(1f));

 if (mAnimator2 != null && mAnimator2.isRunning()) {
  mAnimator2.cancel();
 }
 mAnimator2 = ObjectAnimator.ofFloat(this, "phase2", 0f, 1f);
 mAnimator2.setDuration(time);
 mAnimator2.addUpdateListener(this);
 mAnimator2.start();
 mAnimator2.setInterpolator(new AccelerateInterpolator(1f));
 mAnimator2.setStartDelay(delay);

 if (mAnimator3 != null && mAnimator3.isRunning()) {
  mAnimator3.cancel();
 }
 mAnimator3 = ObjectAnimator.ofFloat(this, "phase3", 0f, 1f);
 mAnimator3.setDuration(time);
 mAnimator3.addUpdateListener(this);
 mAnimator3.start();
 mAnimator3.setInterpolator(new AccelerateInterpolator(1f));
 mAnimator3.setStartDelay(delay * 2);
 }

 /**
 * 跟新小球的位置
 *
 * @param value
 * @param fllowers
 */
 private void updateValue(float value, List<Fllower> fllowers) {
 for (Fllower fllower : fllowers) {
  fllower.setValue(value);
 }
 }

 /**
 * 动画改变回调
 */
 @Override
 public void onAnimationUpdate(ValueAnimator arg0) {

 updateValue(getPhase1(), fllowers1);
 updateValue(getPhase2(), fllowers2);
 updateValue(getPhase3(), fllowers3);
 Log.i(tag, getPhase1() + "");
 invalidate();
 }

 public float getPhase1() {
 return phase1;
 }

 public void setPhase1(float phase1) {
 this.phase1 = phase1;
 }

 public float getPhase2() {
 return phase2;
 }

 public void setPhase2(float phase2) {
 this.phase2 = phase2;
 }

 public float getPhase3() {
 return phase3;
 }

 public void setPhase3(float phase3) {
 this.phase3 = phase3;
 }

 private String tag = this.getClass().getSimpleName();

 private class CPoint {

 public float x = 0f;
 public float y = 0f;

 /**
  * x-axis distance
  */
 public float dx = 0f;

 /**
  * y-axis distance
  */
 public float dy = 0f;

 public CPoint(float x, float y) {
  this.x = x;
  this.y = y;
 }
 }

}