Android弹幕实现：基于B站弹幕开源系统（7）QQ、微信聊天气泡样式的弹幕

ゞ浴缸里的玫瑰 2024-02-17 22:36 63阅读 0赞

**Android弹幕实现：基于B站弹幕开源系统（7）QQ、微信聊天气泡样式的弹幕**

在附录文章得基础上，改进普通文本弹幕，实现一种特殊效果的文本弹幕，像QQ、微信一样的带有气泡背景的弹幕。实现的重点是在SpannedCacheStuffer。同时要准备若干需要衬在文本弹幕背景部分的.9.png图片。  
  
上层Java代码：

package zhangfei.danmaku;
    
    import android.content.res.Configuration;
    import android.graphics.Canvas;
    import android.graphics.Paint;
    import android.graphics.Rect;
    import android.graphics.drawable.Drawable;
    import android.support.v4.content.ContextCompat;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.text.TextPaint;
    import android.util.Log;
    import android.view.View;
    
    import com.github.lzyzsd.randomcolor.RandomColor;
    
    import java.util.HashMap;
    
    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.DanmakuContext;
    import master.flame.danmaku.danmaku.model.android.SpannedCacheStuffer;
    import master.flame.danmaku.ui.widget.DanmakuView;
    
    public class MainActivity extends AppCompatActivity {
        private DanmakuView mDanmakuView;
        private DanmakuContext mContext;
        private AcFunDanmakuParser mParser;
    
        private AppCompatActivity mActivity;
    
        private final String TAG = getClass().getSimpleName();
    
        private BackgroundCacheStuffer mBackgroundCacheStuffer = new BackgroundCacheStuffer();
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            mActivity = this;
            setContentView(R.layout.activity_main);
    
            mContext = DanmakuContext.create();
            mParser = new AcFunDanmakuParser();
    
            initDanmakuView();
    
            findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    addItems();
                }
            });
        }
    
        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, 10)
                    .setDuplicateMergingEnabled(false)
                    .setScrollSpeedFactor(1.2f)
                    .setScaleTextSize(1.0f)
                    .setCacheStuffer(mBackgroundCacheStuffer, null)
                    // 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 void addItems() {
            RandomColor randomColor = new RandomColor();
    
            int id = (int) (Math.random() * 10) % 3;
    
            int resId;
            switch (id) {
                case 0:
                    resId = R.drawable.bg_01;
                    break;
    
                case 1:
                    resId = R.drawable.bg_02;
                    break;
    
                case 2:
                    resId = R.drawable.bg_03;
                    break;
    
                default:
                    resId = R.drawable.bg_01;
                    break;
            }
    
            String s = "";
            int count = (int) (Math.random() * 100) % 10 + 1;
            for (int i = 0; i < count; i++) {
                s = s + i;
            }
    
            addDanmaKuTextWithBackgroundImage(resId, s, randomColor.randomColor(), false);
        }
    
        /**
         * 绘制背景(自定义弹幕样式)
         */
        private class BackgroundCacheStuffer extends SpannedCacheStuffer {
            @Override
            public void measure(BaseDanmaku danmaku, TextPaint paint, boolean fromWorkerThread) {
                danmaku.padding = 50; // 在背景绘制模式下增加padding
                super.measure(danmaku, paint, fromWorkerThread);
            }
    
            @Override
            public void drawBackground(BaseDanmaku danmaku, Canvas canvas, float left, float top) {
                Object object = danmaku.tag;
                if (object instanceof DanmakuTag) {
                    DanmakuTag danmakuTag = (DanmakuTag) object;
    
                    Drawable drawable = ContextCompat.getDrawable(mActivity, danmakuTag.bitmapResId);
    
                    float height = danmaku.paintHeight;
                    float width = danmaku.paintWidth;
    
                    Rect rect = new Rect(0, 0, (int) width, (int) height);
                    drawable.setBounds(rect);
                    drawable.draw(canvas);
                }
            }
    
            @Override
            public void drawStroke(BaseDanmaku danmaku, String lineText, Canvas canvas, float left,
                    float top, Paint paint) {
                // 禁用描边绘制
            }
        }
    
        private void addDanmaKuTextWithBackgroundImage(int bitmap_resId, String msg,
                                                       int textColor, boolean islive) {
            BaseDanmaku danmaku = mContext.mDanmakuFactory.createDanmaku(BaseDanmaku.TYPE_SCROLL_RL);
            if (danmaku == null) {
                Log.e(TAG, "BaseDanmaku空");
            }
    
            DanmakuTag danmakuTag = new DanmakuTag();
            danmakuTag.bitmapResId = bitmap_resId;
    
            danmaku.setTag(danmakuTag);
    
            danmaku.text = "    " + msg + "      ";
            // 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;
            // danmaku.borderColor=new RandomColor().randomColor();
    
            mDanmakuView.addDanmaku(danmaku);
        }
    
        private class DanmakuTag {
            public int bitmapResId;
        }
    
        @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;
            }
        }
    
        @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：  
![Center][]  
  
  
  
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/68947236  
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  
6，《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》链接：http://blog.csdn.net/zhangphil/article/details/72778984

[Center]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/ff5e472e622c4e92b8b512ec664b31da.png