zoukankan      html  css  js  c++  java
  • 绑定

    BindsDirectlyToSource

    主要用于ObjectDataProvider,绑定到provide自身,而不是provider所包含的对象

    <Window.Resources>
        <ObjectDataProvider x:Key="odp"  ObjectType="{x:Type local:Calculator}" MethodName="Add">
                <ObjectDataProvider.MethodParameters>
                    <system:String>0</system:String>
                    <system:String>0</system:String>
                </ObjectDataProvider.MethodParameters>
        </ObjectDataProvider>
      </Window.Resources>
       <StackPanel>
                <TextBox x:Name="textBox1" Margin="5" Text="{Binding Source={StaticResource odp}, Path=MethodParameters[0], BindsDirectlyToSource=true, UpdateSourceTrigger=PropertyChanged}" />

    OneWayToSource 绑定与 OneWay 绑定相反;当目标属性更改时,它会更新源属性。OneWay隐式只读,OneWayToSource隐式只写。 ItemsSource 属性默认支持 OneWay 绑定

    OneTime 使源属性初始化目标属性,但不传播后续更改。它在源值不更改的情况下提供更好的性能

    BindingProxy

    in some cases the DataContext is not accessible: it happens for elements that are not part of the visual or logical tree.
    The solution to our problem is actually quite simple, and takes advantage of the Freezable class. 

    Freezable objects can inherit the DataContext even when they’re not in the visual or logical tree. 

    public class BindingProxy : Freezable
        {
            protected override Freezable CreateInstanceCore()
            {
                return new BindingProxy();
            }
    
            public object Data
            {
                get { return (object)GetValue(DataProperty); }
                set { SetValue(DataProperty, value); }
            }
    
            public static readonly DependencyProperty DataProperty =
                DependencyProperty.Register("Data", typeof(object), typeof(BindingProxy), new UIPropertyMetadata(null));
        }

    We can then declare an instance of this class in the resources of the DataGrid, and bind the Data property to the current DataContext:

    <DataGrid.Resources>
        <local:BindingProxy x:Key="proxy" Data="{Binding}" />
    </DataGrid.Resources>
    The last step is to specify this BindingProxy object (easily accessible with StaticResource) as the Source for the binding:
    <DataGridTextColumn Header="Price" Binding="{Binding Price}" IsReadOnly="False"
                        Visibility="{Binding Data.ShowPrice,
                            Converter={StaticResource visibilityConverter},
                            Source={StaticResource proxy}}"/>

    DataGrid 只读模式的绑定触发

    In a DataGrid the bindings do not get updated until you end editing of the row. Try adding UpdateSourceTrigger=PropertyChanged to the RadioButton's binding expression to update bindings immediately:

    <RadioButton Name="rbM" GroupName="CMGrp" IsChecked="{Binding Path=SELECT, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />

  • 相关阅读:
    斐波拉切数列学习笔记
    BPC全面预算管理学习专题(SAP)
    AjaxPro新发现错误处理
    漂亮的页面向导和Tab插件(Jquery)
    从SAP BPC中Entity维设计的理念考虑Web程序中类似文档库之类的设计该考虑的东西
    VBA之Range,cells,offset,end 的区别(转)
    Jquery.Cookie使用方法(转)
    机场市场采购网(www.caigo365.com)亮点介绍电子书(杂志)的应用
    showModalDialog()showModelessDialog()方法使用详解(转)
    微软依赖注入Unity(转)
  • 原文地址:https://www.cnblogs.com/yetsen/p/13549873.html
Copyright © 2011-2022 走看看