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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <div class="container">
  <div class="row">
    <div class="col-xs-12 col-sm-12 show-danmu">
      <!--弹幕显示-->
    </div>
    <div class="col-xs-8 col-sm-8">
      <input type="text" class="form-control dm-content" placeholder="说点什么吧!" />
    </div>
    <div class="col-sm-2 col-xs-2">
      <button class="btn btn-primary btn-block dm-launch">发射弹幕</button>
    </div>
    <div class="col-sm-2 col-xs-2">
      <button class="btn btn-primary btn-block dm-remove">清除弹幕</button>
    </div>
  </div>
</div>
            
          
!
            
              .show-danmu{
  margin-top: 6%;
  border: 1px solid #000;
  height:500px;
  background: url("http://bizhi.zhuoku.com/2014/01/19/yasina/yasina02.jpg") bottom fixed;
  background-size: 100%;
  font-size: 35px;
  position: relative;
}


            
          
!
            
              $(document).ready(function() {

  var config = {
    authDomain: "wr218314.wilddogio.com",
    syncURL: "https://wr218314.wilddogio.com"
  };

  wilddog.initializeApp(config);

  var ref = wilddog.sync().ref();
  var arr = []; // 此数组用来存放所有的消息元素

  //发射弹幕的事件
  $(".dm-launch").click(function() {
    // 获取输入框的数据
    var text = $(".dm-content").val();
    // 将数据写到云端 message 节点下,child 用来定位子节点
    ref.child('message').push(text);
    
    $(".dm-content").val('');
  });

   //响应按键点击事件
	  $(".dm-content").keypress(function(event) {
	    if (event.keyCode == "13") {
	      $(".dm-launch").trigger('click');
	    }
	  });
  
  //清屏的事件
  $(".dm-remove").click(function() {
    ref.remove();
    arr = [];
    $('.show-danmu').empty();
  });

  // 绑定 'child_added' 事件,当 message 节点下有子节点新增时,就会触发回调,回调的 `snapshot` 对象包含了新增的数据
  ref.child('message').on('child_added', function(snapshot) {
    var text = snapshot.val();
    arr.push(text);
    var textObj = $("<div class=" / dm - message / "></div>");
    textObj.text(text);
    $(".shou-danmu").append(textObj);
    moveObj(textObj);
  })

  //滚动以及逐行显示
  var topMin = $('.show-danmu').offset().top; // 显示框距顶部距离
  var topMax = topMin + $('.show-danmu').height(); // 显示框底部距顶部距离
  var _top = topMin; // 每个滚动消息距顶部距离


  var moveObj = function(obj) {
    var _left = $('.show-danmu').width() - obj.width();
    _top = _top + 50;
    if (_top > (topMax - 50)) {
      _top = topMin;
    }
    obj.css({
      left: _left,
      top: _top,
      color: getRandomColor() // 获取随机颜色,之后讲
    });
    var time = 20000 + 10000 * Math.random();
    // animate() 方法执行 CSS 属性集的自定义动画。逐渐改变的,这样就可以创建动画效果。
    obj.animate({
      left: "-" + _left + "px" // 让消息距左距离逐渐减小,产生右向左滚动动画。
    }, time, function() {
        obj.remove();
    });
  }

  //3秒显示一次
  var getAndRun = function() {
    if (arr.length > 0) {
      var n = Math.floor(Math.random() * arr.length + 1) - 1;
      var textObj = $("<div>" + arr[n] + "</div>");
      textObj.css("position", "absolute");
      $(".show-danmu").append(textObj);
      moveObj(textObj);
    }
    setTimeout(getAndRun, 3000);
  }

  //随机颜色
  var getRandomColor = function() {
    return '#' + (function(h) {
      return new Array(7 - h.length).join("0") + h
    })((Math.random() * 0x1000000 << 0).toString(16))
  }
  getAndRun();
});
            
          
!
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