Android仿echo评论弹幕效果-技术圈

我是echo回声的忠实粉丝，里面的各种3D音效真是美滴很美滴很。这个App的开发组是完美主义，被深深吸引无法自拔。尤其是弹幕的神评论更加搞笑。今天，我就仿着echo的弹幕纯手打了一个效果出来。

是时候来一发炸裂的开场了：

写这个功能之前，我低下头深深沉思，我要做什么功能呢，要怎么做到呢？写程序要一步一步来，步子大了会扯着蛋，于是我在纸上列出：

1、创建一个Relativelayout,在里面添加一个moveView(每一个弹幕view)。

2、写下这个moveView和该布局。

3、给moveView添加translation动画从右往左跑出，动画开始添加，动画结束移除该view。

4、用定时器不停创建多个moveView从右往左动画。

5、在根据Relativelayout的高度范围，创建随机高度，设置给moveView的上边界距离。

6、创建数据源，包括头像id，名字，弹幕文字内容

7、设置随机出现间隔时间；设置背景图（这里我是截的背景图）

我用双手成就我的设想：

1、创建MoveView布局

<LinearLayout    xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="horizontal"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:gravity="center_vertical">
    <ImageView        android:id="@+id/avator"        android:layout_width="30dp"        android:layout_height="30dp"        android:background="@mipmap/internet_star"/>
    <LinearLayout        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_marginLeft="10dp"        android:background="@drawable/shape_text">
        <TextView            android:id="@+id/tv_name"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="Jack ma"            android:textColor="#2ecc71"/>
        <TextView            android:id="@+id/tv_content"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_marginLeft="8dp"            android:text="哈哈哈"            android:singleLine="true"            android:background="@drawable/shape_text"            android:textColor="#000" />    </LinearLayout>
</LinearLayout>

2、创建moveview，传入Relativelayout高度随机设置params.topMargin属性值，即随机垂直高度出现。

public class MoveView extends LinearLayout{    private View rootView;    private ImageView ivAvator;    private TextView tvName;    private TextView tvContent;
    public MoveView(Context context, DanmuBean danmuBean) {        super(context);
        rootView = inflate(context,R.layout.item,null);        addView(rootView);        init(danmuBean);    }
    private void init(DanmuBean danmuBean) {        ivAvator = rootView.findViewById(R.id.avator);        tvName = rootView.findViewById(R.id.tv_name);        tvContent = rootView.findViewById(R.id.tv_content);
        ivAvator.setImageResource(danmuBean.getAvatorId());        tvName.setText(danmuBean.getUserName());        tvContent.setText(danmuBean.getContent());    }
    /**     * 设置随机出现垂直位置     */    public void randomVerticalPos(int heightPixels){        int randonTop = (int) (Math.random()*heightPixels);
        RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) getLayoutParams();        params.topMargin = randonTop;        setLayoutParams(params);    }
}

3、随机设置Translationg动画的duration，即实现随机移动速度；

    private void startTranslateAnim(final View view){        int randomDuration = (int) (Math.random()*2000 + 7000);        TranslateAnimation anim = new TranslateAnimation(widthPixels,-widthPixels,0,0);        anim.setDuration(randomDuration);        anim.setAnimationListener(new Animation.AnimationListener() {            @Override            public void onAnimationStart(Animation animation) {
            }
            @Override            public void onAnimationEnd(Animation animation) {                removeView(view);            }
            @Override            public void onAnimationRepeat(Animation animation) {
            }        });        view.startAnimation(anim);    }

4、handler随机间隔创建moveview

    private Handler handler = new Handler(){        @Override        public void handleMessage(Message msg) {            addTextView();
            //弹幕出现间隔时间400-700ms            int randomDelay = (int) (Math.random()*300+400);            handler.sendEmptyMessageDelayed(0,randomDelay);        }    };
    private void addTextView(){        if(curPos == datas.size()){  //循环播放            curPos = 0;        }        MoveView moveView = new MoveView(getContext(),datas.get(curPos++));        addView(moveView);        moveView.randomVerticalPos(heightPixels);        startTranslateAnim(moveView);    }

5、模拟网络请求弹幕数据列表，这里包括，头像、用户名、弹幕内容

    private List loadData(){        ArrayList<DanmuBean> datas = new ArrayList<>();        datas.add(new DanmuBean(0,R.mipmap.internet_star,"小强","女神我爱你！"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"Jack ma","妈妈问我为什么跪着听歌"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_lori,"习大大","歌词特别美"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_robot,"宝强","全世界都安静了"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"宝宝","听到放不下耳机，听到耳朵痛都不放下，哈哈哈"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"我是大神","中国好声音，I want you"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"茜茜","一天脑子里都在唱这首歌"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"Bangbangbang","有故事，好听"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"stalse","我就是为了你开的会员"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"hehe","太好听了.."));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_robot,"小强","女神我爱你！"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"Jack ma","妈妈问我为什么跪着听歌"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"习大大","歌词特别美"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"宝强","全世界都安静了"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"宝宝","听到放不下耳机，听到耳朵痛都不放下，哈哈哈"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"我是大神","中国好声音，I want you"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_robot,"茜茜","一天脑子里都在唱这首歌"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"Bangbangbang","有故事，好听"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"stalse","我就是为了你开的会员"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"hehe","太好听了.."));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"小强","女神我爱你！"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_robot,"Jack ma","妈妈问我为什么跪着听歌"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"习大大","歌词特别美"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"宝强","全世界都安静了"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"宝宝","听到放不下耳机，听到耳朵痛都不放下，哈哈哈"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"我是大神","中国好声音，I want you"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_uncle,"茜茜","一天脑子里都在唱这首歌"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"Bangbangbang","有故事，好听"));        datas.add(new DanmuBean(0,R.mipmap.make_music_voice_changer_funny,"stalse","我就是为了你开的会员"));        datas.add(new DanmuBean(0,R.mipmap.internet_star,"hehe","太好听了.."));
        return datas;    }

源码地址：

https://github.com/18380438200/Danmu

到这里就结束啦。