OnIdiom for Grid columnspan

Question

我需要使用OnIdiom进行网格列定义，但它不起作用。请参阅下面的代码。谁能告诉我我做错了什么并建议解决方案？

 <Grid.ColumnDefinitions>
                    <ColumnDefinition>
                        <ColumnDefinition.Width>
                            <OnIdiom  x:TypeArguments="GridLength" Tablet="64.9*" Phone="99.8*"/>
                        </ColumnDefinition.Width>
                    </ColumnDefinition>
                    <ColumnDefinition>
                        <ColumnDefinition.Width>
                            <OnIdiom  x:TypeArguments="GridLength" Tablet="0.1*" Phone="0.1*"/>
                        </ColumnDefinition.Width>
                    </ColumnDefinition>
                    <ColumnDefinition>
                        <ColumnDefinition.Width>
                            <OnIdiom  x:TypeArguments="GridLength" Tablet="35*" Phone="0.1*"/>
                        </ColumnDefinition.Width>
                    </ColumnDefinition>

这没有用，所以我做了：

<Grid.ColumnSpan>
       <OnIdiom x:TypeArguments="x:Int32" Phone="3" Tablet="1"/>
</Grid.ColumnSpan>

这也没有帮助。

Answer 1

override void OnSizeAllocated(double width, double height)
{
     //according with height and width you can design your layouts
     if (Device.Idiom == TargetIdiom.Phone)
     {
       // layout views vertically
     } 
     else
     {
       // layout views horizontally or use different Page
     }
}

Answer 2

x：DataType代替x：TypeArguments对我有用。

<Grid.RowDefinitions>
    <RowDefinition >
        <RowDefinition.Height>
            <OnIdiom x:DataType="GridLength" Tablet=".25*" Phone="0.075*" />
        </RowDefinition.Height>
    </RowDefinition>
    <RowDefinition >
        <RowDefinition.Height>
            <OnIdiom x:DataType="GridLength" Tablet="*" Phone="0.85*" />
        </RowDefinition.Height>
    </RowDefinition>
    <RowDefinition >
        <RowDefinition.Height>
            <OnIdiom x:DataType="GridLength" Tablet=".25*" Phone="0.075*" />
        </RowDefinition.Height>
    </RowDefinition>
</Grid.RowDefinitions>