Question

我正在尝试将Enum绑定到ComboBox。我见过很多人使用ObjectDataProvider，但我似乎无法访问它。我还注意到有些人在Window.Resources而不是Page.Resources中使用它，但我无法在Page.Resources找到它的用法。我一直在寻找解决方案几个小时。

到目前为止我所拥有的：

XAML

<Page
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Sports;assembly=Sports"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:ViewModel="using:Sports.ViewModel"
xmlns:model="using:Sports.Model"
xmlns:system="using:System"


x:Class="Sports.MainPage"
mc:Ignorable="d">

<Page.DataContext>
    <ViewModel:CreateSubsVM/>
</Page.DataContext>
    <Page.Resources>

    <ObjectDataProvider></ObjectDataProvider>
    </Page.Resources>
  </Grid>
</Page>

C＃

public enum SubsAmount
{
    [Display(Description = "One Year")]
    Oneyear = 0,
    [Display(Description = "Two Years")]
    TwoYears = 1,
    [Display(Description = "Three Years")]
    ThreeYears = 2
}


public class ComboboxConverter: IValueConverter
{

    public string GetEnumValues(Enum enumObj)
    {
        DisplayAttribute attribute = enumObj.GetType().
        GetRuntimeField(enumObj.ToString()).
        GetCustomAttributes(typeof(SubsAmount), false).
        SingleOrDefault() as DisplayAttribute;
        return attribute == null ? enumObj.ToString() : attribute.Description;
    }


    public object Convert(object value, Type targetType, object parameter, string language)
    {
        return GetEnumValues((Enum) value);
    }

    public object ConvertBack(object value, Type targetType, object parameter, string language)
    {
        return Enum.ToObject(targetType, value);
    }
}

Answer 1

以下是页面对象的示例（根据MSDN documentation，对页面使用ObjectDataProvider没有任何限制）：

更新＃1

<强>的Xaml

@MappedSuperclass
public abstract class EntityBase implements IEntity {
...
}

@MappedSuperclass
public abstract class StandardEntityJpaImpl extends EntityBase implements IStandardEntity {
...
}

@MappedSuperclass
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public abstract class ArtifactBase extends StandardEntityJpaImpl {
...
}

@Entity
@Table(name="artifact")
public class Artifact extends ArtifactBase implements Comparable<Artifact> {
...
}

@Entity
@Table(name="artifact2")
public class Artifact2 extends ArtifactBase implements Comparable<Artifact>    {
...
}

@Entity
@Table(name="artifact3")
public class Artifact3 extends ArtifactBase implements Comparable<Artifact> {
...
}

@Entity
@Table(name="reference")
public class Reference extends StandardEntityJpaImpl implements Comparable<Artifact> {
...
}

以下是自定义数据提供者代码

   [Persistence Model][1] http://i.stack.imgur.com/2uynO.png

属性代码和枚举：

<Page x:Class="PageBasedApp.MyPage"
  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:pageBasedApp="clr-namespace:PageBasedApp"
  mc:Ignorable="d" 
  d:DesignHeight="300" d:DesignWidth="300"
Title="MyPage">
<Page.Resources>
    <ObjectDataProvider x:Key="Gestures" MethodName="GetValues" ObjectType="{x:Type ApplicationGesture}">
        <ObjectDataProvider.MethodParameters>
            <x:Type TypeName="ApplicationGesture" />
        </ObjectDataProvider.MethodParameters>
    </ObjectDataProvider>
    <ObjectDataProvider x:Key="SubAmounts" MethodName="GetShortListOfApplicationGestures" ObjectType="{x:Type pageBasedApp:DisplayAttributeBasedObjectDataProvider}">
        <ObjectDataProvider.MethodParameters>
            <x:Type TypeName="pageBasedApp:SubsAmount" />
        </ObjectDataProvider.MethodParameters>
    </ObjectDataProvider>
</Page.Resources>

<Grid>
    <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center" >
        <Label Content="All Gestures:"/>
        <ComboBox ItemsSource="{Binding Source={StaticResource Gestures}}" Width="150"/>
        <Label Content="Sub Amounts:"/>
        <ComboBox ItemsSource="{Binding Source={StaticResource SubAmounts}}" Width="150"/>
    </StackPanel>
</Grid>

看起来如何：

P.S。你在这里不需要任何转换器。问候。

如何使用ObjectDataProvider将枚举绑定到XAML中的ComboBox

1 个答案: