Toast
toast 用于临时显示某些信息，并且会在数秒后自动消失。这些信息通常是轻量级操作的成功信息。
提醒：WeUI 不推荐在 toast 中展示失败状态，失败状态应该使用 Alert 明确告知用户失败原因
<div id="toast" style="display: none;">
<div class="weui_mask_transparent"></div>
<div class="weui_toast">
<i class="weui_icon_toast"></i>
<p class="weui_toast_content">已完成</p>
</div>
</div>loading 形态类似于 toast，只是图标是旋转的 loading，用于从服务端拉取数据/向服务端提交数据等耗时操作。
<div id="loadingToast" class="weui_loading_toast" style="display:none;">
<div class="weui_mask_transparent"></div>
<div class="weui_toast">
<div class="weui_loading">
<!-- :) -->
<div class="weui_loading_leaf weui_loading_leaf_0"></div>
<div class="weui_loading_leaf weui_loading_leaf_1"></div>
<div class="weui_loading_leaf weui_loading_leaf_2"></div>
<div class="weui_loading_leaf weui_loading_leaf_3"></div>
<div class="weui_loading_leaf weui_loading_leaf_4"></div>
<div class="weui_loading_leaf weui_loading_leaf_5"></div>
<div class="weui_loading_leaf weui_loading_leaf_6"></div>
<div class="weui_loading_leaf weui_loading_leaf_7"></div>
<div class="weui_loading_leaf weui_loading_leaf_8"></div>
<div class="weui_loading_leaf weui_loading_leaf_9"></div>
<div class="weui_loading_leaf weui_loading_leaf_10"></div>
<div class="weui_loading_leaf weui_loading_leaf_11"></div>
</div>
<p class="weui_toast_content">数据加载中</p>
</div>
</div>