Android弹幕实现：基于B站弹幕开源系统（6）带用户头像且头像从网络加载

在附录文章1,2,3,4，5基础上，实现一种特殊弹幕效果，实现弹幕带发表者头像。这种需求在一些开发场景中比较有用，比如在一些视频中，不同等级的用户显示不同的头像，或者本身发出来的弹幕就要求头像。

代码：

package zhangfei.danmaku;

import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.support.annotation.NonNull;
import android.support.v4.graphics.drawable.RoundedBitmapDrawable;
import android.support.v4.graphics.drawable.RoundedBitmapDrawableFactory;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Spannable;
import android.text.SpannableStringBuilder;
import android.text.style.BackgroundColorSpan;
import android.text.style.ImageSpan;
import android.util.Log;
import android.view.View;

import java.util.HashMap;
import java.util.concurrent.Callable;

import io.reactivex.Observable;
import io.reactivex.ObservableSource;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.disposables.CompositeDisposable;
import io.reactivex.observers.DisposableObserver;
import io.reactivex.schedulers.Schedulers;
import master.flame.danmaku.controller.IDanmakuView;
import master.flame.danmaku.danmaku.model.BaseDanmaku;
import master.flame.danmaku.danmaku.model.DanmakuTimer;
import master.flame.danmaku.danmaku.model.IDanmakus;
import master.flame.danmaku.danmaku.model.IDisplayer;
import master.flame.danmaku.danmaku.model.android.BaseCacheStuffer;
import master.flame.danmaku.danmaku.model.android.DanmakuContext;
import master.flame.danmaku.danmaku.model.android.SpannedCacheStuffer;
import master.flame.danmaku.ui.widget.DanmakuView;

import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;


public class MainActivity extends AppCompatActivity {
    private DanmakuView mDanmakuView;
    private DanmakuContext mContext;
    private AcFunDanmakuParser mParser;

    private final String TAG = getClass().getSimpleName();

    private OkHttpClient mOkHttpClient;
    private CompositeDisposable mCompositeDisposable = new CompositeDisposable();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mOkHttpClient = new OkHttpClient();

        mContext = DanmakuContext.create();
        mParser = new AcFunDanmakuParser();

        initDanmakuView();

        final String url="http://avatar.csdn.net/9/7/A/1_zhangphil.jpg";

        findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                addItems(url);
            }
        });
    }

    private void initDanmakuView() {
        // 设置最大显示行数
        HashMap<Integer, Integer> maxLinesPair = new HashMap<>();
        maxLinesPair.put(BaseDanmaku.TYPE_SCROLL_RL, 5); // 滚动弹幕最大显示5行
        // 设置是否禁止重叠
        HashMap<Integer, Boolean> overlappingEnablePair = new HashMap<Integer, Boolean>();
        overlappingEnablePair.put(BaseDanmaku.TYPE_SCROLL_RL, true);
        overlappingEnablePair.put(BaseDanmaku.TYPE_FIX_TOP, true);

        mDanmakuView = (DanmakuView) findViewById(R.id.sv_danmaku);

        mContext.setDanmakuStyle(IDisplayer.DANMAKU_STYLE_STROKEN, 3)
                .setDuplicateMergingEnabled(false).setScrollSpeedFactor(1.2f).setScaleTextSize(1.2f)
                .setCacheStuffer(new SpannedCacheStuffer(), mCacheStufferAdapter) // 图文混排使用SpannedCacheStuffer
                // .setCacheStuffer(new BackgroundCacheStuffer()) //
                // 绘制背景使用BackgroundCacheStuffer
                .setMaximumLines(maxLinesPair)
                .preventOverlapping(overlappingEnablePair).setDanmakuMargin(40);

        if (mDanmakuView != null) {
            mDanmakuView.setCallback(new master.flame.danmaku.controller.DrawHandler.Callback() {
                @Override
                public void updateTimer(DanmakuTimer timer) {
                }

                @Override
                public void drawingFinished() {

                }

                @Override
                public void danmakuShown(BaseDanmaku danmaku) {

                }

                @Override
                public void prepared() {
                    mDanmakuView.start();
                }
            });

            mDanmakuView.setOnDanmakuClickListener(new IDanmakuView.OnDanmakuClickListener() {

                @Override
                public boolean onDanmakuClick(IDanmakus danmakus) {
                    BaseDanmaku latest = danmakus.last();
                    if (null != latest) {
                        return true;
                    }
                    return false;
                }

                @Override
                public boolean onDanmakuLongClick(IDanmakus danmakus) {
                    return false;
                }

                @Override
                public boolean onViewClick(IDanmakuView view) {
                    return false;
                }
            });

            mDanmakuView.prepare(mParser, mContext);
            // mDanmakuView.showFPS(true);
            mDanmakuView.enableDanmakuDrawingCache(true);
        }
    }

    private BaseCacheStuffer.Proxy mCacheStufferAdapter = new BaseCacheStuffer.Proxy() {
        @Override
        public void prepareDrawing(final BaseDanmaku danmaku, boolean fromWorkerThread) {

        }

        @Override
        public void releaseResource(BaseDanmaku danmaku) {
            // TODO 重要:清理含有ImageSpan的text中的一些占用内存的资源 例如drawable
        }
    };


    private void addItems(final String url) {
        DisposableObserver disposableObserver = new DisposableObserver<Bitmap>() {

            @Override
            public void onNext(@NonNull Bitmap bmp) {
                addDanmaKuShowTextAndImage(bmp, "zhang phil @ csdn", Color.DKGRAY, Color.RED, false);
            }

            @Override
            public void onComplete() {

            }

            @Override
            public void onError(Throwable e) {
                Log.e(TAG, e.toString(), e);
            }
        };

        mCompositeDisposable.add(
                getBitmapObservable(url)
                        .subscribeOn(Schedulers.io())
                        .observeOn(AndroidSchedulers.mainThread())
                        .subscribeWith(disposableObserver)
        );
    }

    private Observable<Bitmap> getBitmapObservable(@NonNull final String url) {
        return Observable.defer(new Callable<ObservableSource<Bitmap>>() {
            @Override
            public ObservableSource<Bitmap> call() throws Exception {
                Bitmap bmp = null;

                //同步方法返回观察者需要的数据结果
                //在这里处理线程化的操作

                Request request = new Request.Builder().url(url).build();
                Response response = mOkHttpClient.newCall(request).execute();
                try {
                    if (response.isSuccessful()) {
                        byte[] bytes = response.body().bytes();
                        bmp = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }

                return Observable.just(bmp);
            }
        });
    }


    private void addDanmaKuShowTextAndImage(Bitmap bitmap, String msg, int textColor, int bgColor, boolean islive) {
        BaseDanmaku danmaku = mContext.mDanmakuFactory.createDanmaku(BaseDanmaku.TYPE_SCROLL_RL);
        if (danmaku == null) {
            Log.e(TAG, "BaseDanmaku空");
        }

        //最里面的图像
        RoundedBitmapDrawable drawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap);
        drawable.setCircular(true);
        drawable.setAntiAlias(true);
        drawable.setCornerRadius(Math.max(bitmap.getWidth(), bitmap.getHeight()));
        drawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight());

        SpannableStringBuilder spannable = createSpannable(drawable, msg, bgColor);
        danmaku.text = spannable;
        danmaku.padding = 5;
        danmaku.priority = 1; // 一定会显示, 一般用于本机发送的弹幕
        danmaku.isLive = islive;
        danmaku.setTime(mDanmakuView.getCurrentTime() + 1200);
        danmaku.textSize = 25f * (mParser.getDisplayer().getDensity() - 0.6f);
        danmaku.textColor = textColor;
        danmaku.textShadowColor = 0; // 重要：如果有图文混排，最好不要设置描边(设textShadowColor=0)，否则会进行两次复杂的绘制导致运行效率降低
        //danmaku.underlineColor = Color.GREEN;

        mDanmakuView.addDanmaku(danmaku);
    }

    private SpannableStringBuilder createSpannable(Drawable drawable, String msg, int color) {
        String text = "image";
        SpannableStringBuilder spannableStringBuilder = new SpannableStringBuilder(text);
        spannableStringBuilder.append(msg);

        ImageSpan span = new ImageSpan(drawable);// ImageSpan.ALIGN_BOTTOM);
        spannableStringBuilder.setSpan(span, 0, text.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

        spannableStringBuilder.setSpan(new BackgroundColorSpan(color), 0, spannableStringBuilder.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
        return spannableStringBuilder;
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (mDanmakuView != null && mDanmakuView.isPrepared()) {
            mDanmakuView.pause();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (mDanmakuView != null && mDanmakuView.isPrepared() && mDanmakuView.isPaused()) {
            mDanmakuView.resume();
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (mDanmakuView != null) {
            // dont forget release!
            mDanmakuView.release();
            mDanmakuView = null;
        }

        //取消所有Okhttp的网络请求
        mOkHttpClient.dispatcher().cancelAll();

        mCompositeDisposable.clear();
    }

    @Override
    public void onBackPressed() {
        super.onBackPressed();
        if (mDanmakuView != null) {
            // dont forget release!
            mDanmakuView.release();
            mDanmakuView = null;
        }
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
            mDanmakuView.getConfig().setDanmakuMargin(20);
        } else if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
            mDanmakuView.getConfig().setDanmakuMargin(40);
        }
    }
}

代码运行结果：

附录：
1，《Android弹幕实现：基于B站弹幕开源系统（1）》链接：http://blog.csdn.net/zhangphil/article/details/68067100 
2，《Android弹幕实现：基于B站弹幕开源系统（2）》链接：http://blog.csdn.net/zhangphil/article/details/68114226 
3，《Android弹幕实现：基于B站弹幕开源系统（3）-文本弹幕的完善和细节调整》链接：http://blog.csdn.net/zhangphil/article/details/68485505
4，《Android弹幕实现：基于B站弹幕开源系统（4）-重构》链接：http://blog.csdn.net/zhangphil/article/details/65936066
5，《Android弹幕实现：基于B站弹幕开源系统（5）-抽象和复用》链接：http://blog.csdn.net/zhangphil/article/details/69400428