Android实现视频弹幕功能

<activity android:name=".MainActivity"
  android:configChanges="keyboardHidden|orientation|screenLayout|screenSize"
  android:screenOrientation="landscape">
  <intent-filter>
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
  </intent-filter>
</activity>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent" android:layout_height="match_parent"
  android:background="#000000">
 
  <VideoView
    android:id="@+id/video_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_centerInParent="true"/>
 
  <master.flame.danmaku.ui.widget.DanmakuView
    android:id="@+id/danmu"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
  <LinearLayout
    android:id="@+id/operate_layout"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:layout_alignParentBottom="true"
    android:visibility="gone">
    <EditText
      android:id="@+id/edit"
      android:layout_width="0dp"
      android:layout_height="match_parent"
      android:layout_weight="1"
      android:layout_marginLeft="50dp"
      android:textColor="#ffffff"
      android:imeOptions="flagNoExtractUi"
      />
    <Button
      android:layout_width="wrap_content"
      android:layout_height="match_parent"
      android:id="@+id/send"
      android:textSize="20sp"
      android:background="#00000000"
      android:textColor="#ffffff"
      android:text="发送"/>
  </LinearLayout>
</RelativeLayout>

package com.mega.mydanmudemo;
 
import android.content.Context;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.VideoView;
 
import java.util.Random;
 
import master.flame.danmaku.controller.DrawHandler;
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.android.DanmakuContext;
import master.flame.danmaku.danmaku.model.android.Danmakus;
import master.flame.danmaku.danmaku.parser.BaseDanmakuParser;
import master.flame.danmaku.ui.widget.DanmakuView;
 
public class MainActivity extends AppCompatActivity {
 
  private boolean showDanma;
  private VideoView mVideoView;
  private DanmakuView mDanmu;
  private BaseDanmakuParser mBaseDanmakuParser = new BaseDanmakuParser() {//弹幕解析器
    @Override
    protected IDanmakus parse() {
      return new Danmakus();
    }
  };
  private DanmakuContext danmakuContext;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    init();
    setOnListener();
  }
 
  /***
   * 一些初始化工作
   */
  private void init() {
    String uri = "android.resource://" + getPackageName() + "/" + R.raw.danmu;
    mVideoView = (VideoView)findViewById(R.id.video_view);
    mVideoView.setVideoPath(uri);
    mVideoView.start();
 
    mDanmu = (DanmakuView)findViewById(R.id.danmu);
    mDanmu.enableDanmakuDrawingCache(true);
    danmakuContext = DanmakuContext.create();
    danmakuContext.setScaleTextSize(1.1f);
    mDanmu.prepare(mBaseDanmakuParser,danmakuContext);
  }
 
  /***
   * 弹幕的准备工作，发送按钮监听。。
   */
  private void setOnListener(){
 
    mDanmu.setCallback(new DrawHandler.Callback() {
      @Override
      public void prepared() {
        showDanma = true;
        mDanmu.start();//启动弹幕
        generateSomeDanmu();
      }
 
      @Override
      public void updateTimer(DanmakuTimer timer) {
 
      }
 
      @Override
      public void danmakuShown(BaseDanmaku danmaku) {
 
      }
 
      @Override
      public void drawingFinished() {
 
      }
    });
 
    final LinearLayout operate_view = (LinearLayout)findViewById(R.id.operate_layout);
    Button send = (Button)findViewById(R.id.send);
    final EditText editText = (EditText)findViewById(R.id.edit);
 
    mDanmu.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View view) {
        if (operate_view.getVisibility() == View.GONE){
          operate_view.setVisibility(View.VISIBLE);
        }else{
          operate_view.setVisibility(View.GONE);
        }
      }
    });
    send.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View view) {
        String content = editText.getText().toString();
        if (!TextUtils.isEmpty(content)){
          InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
          imm.hideSoftInputFromWindow(editText.getWindowToken(),0);
          addDamu(content,true);
          editText.setText("");
          operate_view.setVisibility(View.GONE);
        }
      }
    });
 
    getWindow().getDecorView().setOnSystemUiVisibilityChangeListener(new View.OnSystemUiVisibilityChangeListener() {
      @Override
      public void onSystemUiVisibilityChange(int visibility) {
        if (visibility == View.SYSTEM_UI_FLAG_VISIBLE){
          onWindowFocusChanged(true);
        }
      }
    });
  }
 
  /***
   * 随机产生一些弹幕
   */
  private void generateSomeDanmu() {
    new Thread(new Runnable() {
      @Override
      public void run() {
        while (showDanma){
          int time = new Random().nextInt(300);
          String content = "" + time;
          addDamu(content,false);
          try {
            Thread.sleep(time);
          }catch (Exception e){
            e.printStackTrace();
          }
        }
      }
    }).start();
  }
 
  /***
   * 添加弹幕的方法
   * @param content 弹幕的内容
   * @param isSelf 是否是用户发送的弹幕
   */
  private void addDamu(String content,boolean isSelf) {
    BaseDanmaku danmaku = danmakuContext.mDanmakuFactory.createDanmaku(BaseDanmaku.TYPE_SCROLL_RL);
    danmaku.text = content;
    danmaku.padding = 5;
    danmaku.priority = 0;
    danmaku.textSize = sp2px(20);
    danmaku.setTime(mDanmu.getCurrentTime());
    danmaku.textColor = Color.argb(new Random().nextInt(256), new Random().nextInt(256),
        new Random().nextInt(256),new Random().nextInt(256));
    if (isSelf){
      danmaku.borderColor = Color.GREEN;
    }
    mDanmu.addDanmaku(danmaku);
  }
  
  private float sp2px(int i) {
    final float fontScale = getResources().getDisplayMetrics().scaledDensity;
    return (int)(i* fontScale +0.5f);
  }
 
  @Override
  protected void onPause() {
    super.onPause();
    if (mDanmu!= null && mDanmu.isPrepared()){
      mDanmu.pause();
    }
  }
 
  @Override
  protected void onResume() {
    super.onResume();
    if (mDanmu!=null&& mDanmu.isPrepared()&& mDanmu.isPaused()){
      mDanmu.resume();
    }
  }
 
  @Override
  protected void onDestroy() {
    super.onDestroy();
    showDanma = false;
    if (mDanmu != null){
      mDanmu.release();
      mDanmu = null;
    }
  }
 
  @Override
  public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    if (hasFocus && Build.VERSION.SDK_INT>=19){
      View deview = getWindow().getDecorView();
      deview.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
      |View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
      |View.SYSTEM_UI_FLAG_FULLSCREEN
      |View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
      |View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
      |View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
    }
  }
}