实现这样的效果，你要知道贝塞尔曲线，何谓贝塞尔曲线？其实就是曲线，嘿嘿，关于曲线的概念大家可以去
Android绘图机制（二）——自定义View绘制形, 圆形, 三角形, 扇形, 椭圆, 曲线,文字和图片的坐标讲解
中看下，我们这里就直接写了
1.activity_main.xml
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
//撒花的区域
<relativelayout
android:id="@+id/rlt_animation_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"></relativelayout>
<button
android:id="@+id/btn_start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignparentbottom="true"
android:layout_centerhorizontal="true"
android:layout_marginbottom="23dp"
android:text="开始撒花">
</button>
</relativelayout>
2.Fllower
package com.lgl.test;
import android.graphics.Bitmap;
import android.graphics.Path;
import java.io.Serializable;
public class Fllower implements Serializable {
private static final long serialVersionUID = 1L;
private Bitmap image;
private float x;
private float y;
private Path path;
private float value;
public Bitmap getResId() {
return image;
}
public void setResId(Bitmap img) {
this.image = img;
}
public float getX() {
return x;
}
public void setX(float x) {
this.x = x;
}
public float getY() {
return y;
}
public void setY(float y) {
this.y = y;
}
public Path getPath() {
return path;
}
public void setPath(Path path) {
this.path = path;
}
public float getValue() {
return value;
}
public void setValue(float value) {
this.value = value;
}
@Override
public String toString() {
return "Fllower [ x=" + x + ", y=" + y + ", path=" + path + ", value="
+ value + "]";
}
}
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 = ;
/**
* 动画间隔
*/
private int delay = ;
int[] ylocations = { -, -, -, };
/**
* 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() * / 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 = ;
/**
* 高度
*/
private int height = ;
/**
* 曲线高度个数分割
*/
private int quadCount = ;
/**
* 曲度
*/
private float intensity = 0.2f;
/**
* 第一批个数
*/
private int fllowerCount = ;
/**
* 创建花
*/
private void builderFollower(int count, List<fllower> fllowers) {
int max = (int) (width * / 4f);
int min = (int) (width / 4f);
Random random = new Random();
for (int i = ; i < count; i++) {
int s = random.nextInt(max) % (max - min + ) + min;
Path path = new Path();
CPoint CPoint = new CPoint(s, ylocations[random.nextInt()]);
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() > ) {
for (int j = ; j < points.size(); j++) {
CPoint point = points.get(j);
if (j == ) {
CPoint next = points.get(j + );
point.dx = ((next.x - point.x) * intensity);
point.dy = ((next.y - point.y) * intensity);
} else if (j == points.size() - ) {
CPoint prev = points.get(j - );
point.dx = ((point.x - prev.x) * intensity);
point.dy = ((point.y - prev.y) * intensity);
} else {
CPoint next = points.get(j + );
CPoint prev = points.get(j - );
point.dx = ((next.x - prev.x) * intensity);
point.dy = ((next.y - prev.y) * intensity);
}
// create the cubic-spline path
if (j == ) {
path.moveTo(point.x, point.y);
} else {
CPoint prev = points.get(j - );
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, , 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 = ; i < quadCount; i++) {
if (i == ) {
points.add(point);
} else {
CPoint tmp = new CPoint(, );
if (random.nextInt() % == ) {
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,
, getResources().getDisplayMetrics());
/**
* @param canvas
* @param fllowers
*/
private void drawFllower(Canvas canvas, List<fllower> fllowers) {
for (Fllower fllower : fllowers) {
float[] pos = new float[];
// 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[], pos[] - 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 * );
}
/**
* 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;
}
}
}
4.MainActivity
package com.lgl.test;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RelativeLayout;
public class MainActivity extends Activity {
private Button btn_start;
// 撒花特效
private RelativeLayout rlt_animation_layout;
private FllowerAnimation fllowerAnimation;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 撒花初始化
rlt_animation_layout = (RelativeLayout) findViewById(R.id.rlt_animation_layout);
rlt_animation_layout.setVisibility(View.VISIBLE);
fllowerAnimation = new FllowerAnimation(this);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.MATCH_PARENT);
fllowerAnimation.setLayoutParams(params);
rlt_animation_layout.addView(fllowerAnimation);
btn_start = (Button) findViewById(R.id.btn_start);
btn_start.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// 开始撒花
fllowerAnimation.startAnimation();
}
});
}
}
