WPF。对于多触发条件，“属性”必须具有非空值
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WPF. Must have non-null value for 'Property' for multitrigger condition
提问by nelly2k
Have multitrigger, one of the conditions is not null, so if StowedAssetDetailedThumbnailViewModel != null then set template
有多重触发，条件之一不为空，所以如果 StowedAssetDetailedThumbnailViewModel != null 那么设置模板
<Style.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected" Value="true" />
<Condition Binding="{Binding Path=StowedAssetDetailedThumbnailViewModel,
Converter={StaticResource isNull}}"
Value="False"/>
</MultiTrigger.Conditions>
<Setter Property="Template" Value="{StaticResource SelectedTemplate}" />
</MultiTrigger>
</Style.Triggers>
Using simple converter:
使用简单的转换器：
return isNull == null;
the error is Must have non-null value for Property
错误是 属性必须具有非空值
UPDATE: Thanks, the final solution is
更新：谢谢，最终的解决方案是
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource Self}}"
Value="true" />
<Condition Binding="{Binding Path=StowedAssetDetailedThumbnailViewModel,
Converter={StaticResource isNull}}"
Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Template" Value="{StaticResource SelectedTemplate}" />
</MultiDataTrigger>
</Style.Triggers>
回答by Patrick Y
You'll want to use a MultiDataTrigger in this case. A MultiTrigger can only be triggered by dependency properties.
在这种情况下，您将需要使用 MultiDataTrigger。MultiTrigger 只能由依赖属性触发。
