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<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();
});
Also see: Tab Triggers