Firebase setValue OutOfMemory异常

Question

我想从Sharedpreferences中读取值并更新到firebase数据库。它工作到昨天都很好。现在它突然开始在下面的代码中抛出OutofMemory异常。

代码：

<UserControl x:Class="CardBox"
                              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
                 xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
                 xmlns:local="clr-namespace:TestingNested"
                 mc:Ignorable="d" 
                 d:DesignHeight="300" d:DesignWidth="300">


      <Viewbox Name="OuterBox">
        <Canvas Width="100" Height="100"  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

          <!-- need outer content dynamically set here  -->


          <Viewbox Name="InnerBox">
            <!-- need inner content dynamically set here  -->


          </Viewbox>

        </Canvas>
      </Viewbox>


    </UserControl>