Android特效專輯（八）——實現心型起泡飛舞的特效，讓你的APP瞬間暖心

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Android特效專輯（八）——實現心型起泡飛舞的特效，讓你的APP瞬間暖心

馬上也要放年假了，家裡估計會沒網，更完這篇的話，可能要到年後了，不過在此期間會把更新內容都儲存在本地，這樣有網就可以發表了，也是極好的，今天說的這個特效，原本是Only上的一個小彩蛋的，我們來看看圖片

只要我點擊了Only這個字，下面就開始上升起起泡了，這個實現起來其實就是一個欲蓋彌彰的動畫而已，準備好三張顏色不一樣的心型圖片咯，這樣的話，我們就開始動手來寫一寫吧！
首先建立一個工程——HeartFaom
準備工作就是準備圖片咯

BezierEvaluator

單位轉換以及計算軌跡

package com.lgl.heartfaom;import android.animation.TypeEvaluator;import android.graphics.PointF;public class BezierEvaluator implements TypeEvaluator<PointF> {    private PointF pointF1;    private PointF pointF2;    public BezierEvaluator(PointF pointF1, PointF pointF2) {        this.pointF1 = pointF1;        this.pointF2 = pointF2;    }    @Override    public PointF evaluate(float time, PointF startValue, PointF endValue) {        float timeLeft = 1.0f - time;        PointF point = new PointF();// 結果        point.x = timeLeft * timeLeft * timeLeft * (startValue.x) + 3                * timeLeft * timeLeft * time * (pointF1.x) + 3 * timeLeft                * time * time * (pointF2.x) + time * time * time * (endValue.x);        point.y = timeLeft * timeLeft * timeLeft * (startValue.y) + 3                * timeLeft * timeLeft * time * (pointF1.y) + 3 * timeLeft                * time * time * (pointF2.y) + time * time * time * (endValue.y);        return point;    }}

PeriscopeLayout

貝茲路徑的計算以及氣泡的實現

package com.lgl.heartfaom;import java.util.Random;import android.animation.Animator;import android.animation.AnimatorListenerAdapter;import android.animation.AnimatorSet;import android.animation.ObjectAnimator;import android.animation.ValueAnimator;import android.annotation.TargetApi;import android.content.Context;import android.graphics.PointF;import android.graphics.drawable.Drawable;import android.os.Build;import android.util.AttributeSet;import android.view.View;import android.view.animation.AccelerateDecelerateInterpolator;import android.view.animation.AccelerateInterpolator;import android.view.animation.DecelerateInterpolator;import android.view.animation.Interpolator;import android.view.animation.LinearInterpolator;import android.widget.ImageView;import android.widget.RelativeLayout;public class PeriscopeLayout extends RelativeLayout {    private Interpolator line = new LinearInterpolator();// 線性    private Interpolator acc = new AccelerateInterpolator();// 加速    private Interpolator dce = new DecelerateInterpolator();// 減速    private Interpolator accdec = new AccelerateDecelerateInterpolator();// 先加速後減速    private Interpolator[] interpolators;    private int mHeight;    private int mWidth;    private LayoutParams lp;    private Drawable[] drawables;    private Random random = new Random();    private int dHeight;    private int dWidth;    public PeriscopeLayout(Context context) {        super(context);        init();    }    public PeriscopeLayout(Context context, AttributeSet attrs) {        super(context, attrs);        init();    }    public PeriscopeLayout(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        init();    }    @TargetApi(Build.VERSION_CODES.LOLLIPOP)    public PeriscopeLayout(Context context, AttributeSet attrs,            int defStyleAttr, int defStyleRes) {        super(context, attrs, defStyleAttr, defStyleRes);        init();    }    private void init() {        // 初始化顯示的圖片        drawables = new Drawable[3];        Drawable red = getResources().getDrawable(R.drawable.pl_red);        Drawable yellow = getResources().getDrawable(R.drawable.pl_yellow);        Drawable blue = getResources().getDrawable(R.drawable.pl_blue);        drawables[0] = red;        drawables[1] = yellow;        drawables[2] = blue;        // 擷取圖的寬高 用於後面的計算        // 注意 我這裡3張圖片的大小都是一樣的,所以我只取了一個        dHeight = red.getIntrinsicHeight();        dWidth = red.getIntrinsicWidth();        // 底部 並且 水平置中        lp = new LayoutParams(dWidth, dHeight);        lp.addRule(CENTER_HORIZONTAL, TRUE);// 這裡的TRUE 要注意 不是true        lp.addRule(ALIGN_PARENT_BOTTOM, TRUE);        // 初始化插補器        interpolators = new Interpolator[4];        interpolators[0] = line;        interpolators[1] = acc;        interpolators[2] = dce;        interpolators[3] = accdec;    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        super.onMeasure(widthMeasureSpec, heightMeasureSpec);        mWidth = getMeasuredWidth();        mHeight = getMeasuredHeight();    }    public void addHeart() {        ImageView imageView = new ImageView(getContext());        // 隨機選一個        imageView.setImageDrawable(drawables[random.nextInt(3)]);        imageView.setLayoutParams(lp);        addView(imageView);        Animator set = getAnimator(imageView);        set.addListener(new AnimEndListener(imageView));        set.start();    }    private Animator getAnimator(View target) {        AnimatorSet set = getEnterAnimtor(target);        ValueAnimator bezierValueAnimator = getBezierValueAnimator(target);        AnimatorSet finalSet = new AnimatorSet();        finalSet.playSequentially(set);        finalSet.playSequentially(set, bezierValueAnimator);        finalSet.setInterpolator(interpolators[random.nextInt(4)]);        finalSet.setTarget(target);        return finalSet;    }    private AnimatorSet getEnterAnimtor(final View target) {        ObjectAnimator alpha = ObjectAnimator.ofFloat(target, View.ALPHA, 0.2f,                1f);        ObjectAnimator scaleX = ObjectAnimator.ofFloat(target, View.SCALE_X,                0.2f, 1f);        ObjectAnimator scaleY = ObjectAnimator.ofFloat(target, View.SCALE_Y,                0.2f, 1f);        AnimatorSet enter = new AnimatorSet();        enter.setDuration(500);        enter.setInterpolator(new LinearInterpolator());        enter.playTogether(alpha, scaleX, scaleY);        enter.setTarget(target);        return enter;    }    private ValueAnimator getBezierValueAnimator(View target) {        // 初始化一個貝塞爾計算機- - 傳入        BezierEvaluator evaluator = new BezierEvaluator(getPointF(2),                getPointF(1));        // 這裡最好畫個圖 理解一下 傳入了起點 和 終點        ValueAnimator animator = ValueAnimator.ofObject(evaluator, new PointF(                (mWidth - dWidth) / 2, mHeight - dHeight),                new PointF(random.nextInt(getWidth()), 0));        animator.addUpdateListener(new BezierListenr(target));        animator.setTarget(target);        animator.setDuration(3000);        return animator;    }    /**     * 擷取中間的兩個 點     *     * @param scale     */    private PointF getPointF(int scale) {        PointF pointF = new PointF();        pointF.x = random.nextInt((mWidth - 100));// 減去100 是為了控制 x軸活動範圍,看效果 隨意~~        // 再Y軸上 為了確保第二個點 在第一個點之上,我把Y分成了上下兩半 這樣動畫效果好一些 也可以用其他方法        pointF.y = random.nextInt((mHeight - 100)) / scale;        return pointF;    }    private class BezierListenr implements ValueAnimator.AnimatorUpdateListener {        private View target;        public BezierListenr(View target) {            this.target = target;        }        @Override        public void onAnimationUpdate(ValueAnimator animation) {            // 這裡擷取到貝茲路徑計算出來的的x y值 賦值給view 這樣就能讓愛心隨著曲線走啦            PointF pointF = (PointF) animation.getAnimatedValue();            target.setX(pointF.x);            target.setY(pointF.y);            // 這裡順便做一個alpha動畫            target.setAlpha(1 - animation.getAnimatedFraction());        }    }    private class AnimEndListener extends AnimatorListenerAdapter {        private View target;        public AnimEndListener(View target) {            this.target = target;        }        @Override        public void onAnimationEnd(Animator animation) {            super.onAnimationEnd(animation);            // 因為不停的add 導致子view數量只增不減,所以在view動畫結束後remove掉            removeView((target));        }    }}

activity_main.xml

布局的實現

<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"    android:background="#000" >    <Button        android:id="@+id/btn_start"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerInParent="true"        android:text="飛舞吧！" />    <com.lgl.heartfaom.PeriscopeLayout        android:id="@+id/periscope"        android:layout_width="match_parent"        android:layout_height="match_parent" >    </com.lgl.heartfaom.PeriscopeLayout></RelativeLayout>

MainActivity

接著就是怎麼去使用它了

package com.lgl.heartfaom;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class MainActivity extends Activity {    private Button btn_start;    // 心型氣泡    private PeriscopeLayout periscopeLayout;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        // 初始化        periscopeLayout = (PeriscopeLayout) findViewById(R.id.periscope);        btn_start = (Button) findViewById(R.id.btn_start);        btn_start.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                // 調用添加泡泡的方法                periscopeLayout.addHeart();            }        });    }}

好，我們接下來就可以運行一下試試實際上的效果了

覺得不錯的點個贊哦！

Demo：http://download.csdn.net/detail/qq_26787115/9422603

Android特效專輯（八）——實現心型起泡飛舞的特效，讓你的APP瞬間暖心