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C# 如何强制更新视图_C#_Wpf_Mvvm_View_Observablecollection - Fatal编程技术网

C# 如何强制更新视图

C# 如何强制更新视图,c#,wpf,mvvm,view,observablecollection,C#,Wpf,Mvvm,View,Observablecollection,我有一个应用程序,它包含两个视图和一个视图模型。 第一个视图[AddView]用于创建对象,第二个视图[ShowView]用于显示对象。ViewModel[DummyData]由一个observedcollection和创建新对象所需的一切组成 我的问题是: 当我从AddView添加对象时,如何强制更新ShowView 这是Dummy的数据 #region Fake Database private static ObservableCollection<Student> f

我有一个应用程序,它包含两个
视图
和一个
视图模型
。 第一个
视图[AddView]
用于创建对象,第二个
视图[ShowView]
用于显示对象。
ViewModel[DummyData]
由一个
observedcollection
和创建新对象所需的一切组成

我的问题是: 当我从
AddView
添加对象时,如何强制更新
ShowView

这是Dummy的数据

#region Fake Database
    private static ObservableCollection<Student> fakeStudentDataLayer;

    public UserDummyData()
    {
        fakeStudentDataLayer = new ObservableCollection<Student>()
        {
            new Student(){Name = "test1", Surname = "surnameTest1", Age = 22, Barcode = "testbarcode1", ClassLetter = 'A', ClassNumber = 6, ID = 1, ParentName = "parentTest1", ParentSurname = "ParentSurnameTitle1", Number = 22, DateOfCreation = new DateTime(2008, 12, 2), LastCheckIn = new DateTime(2014, 3, 9)},
            new Student(){Name = "test2", Surname = "surnameTest2", Age = 22, Barcode = "testbarcode2", ClassLetter = 'B', ClassNumber = 8, ID = 2, ParentName = "parentTest2", ParentSurname = "ParentSurnameTitle2", Number = 22, DateOfCreation = new DateTime(2008, 12, 2), LastCheckIn = new DateTime(2014, 3, 9)},
            new Student(){Name = "test3", Surname = "surnameTest3", Age = 22, Barcode = "testbarcode3", ClassLetter = 'C', ClassNumber = 10, ID = 3, ParentName = "parentTest3", ParentSurname = "ParentSurnameTitle3", Number = 22, DateOfCreation = new DateTime(2008, 12, 2), LastCheckIn = new DateTime(2014, 3, 9) }
        };
    }

    public ObservableCollection<Student> FakeStudentDataLayer
    {
        get { return fakeStudentDataLayer; }
        set { fakeStudentDataLayer = value; RaisePropertyChanged("FakeStudentDataLayer"); }
    }
    #endregion

    #region Commands
    private RelayCommand _addStudentCommand;
    public ICommand NewStudentCommand
    {
        get
        {
            return _addStudentCommand
                ?? (_addStudentCommand = new RelayCommand(() =>
                {
                    //Create new student
                    Student student = new Student();

                    //Set new student's properties
                    //TODO: Add ID value
                    student.Name = Name;
                    student.Surname = Surname;
                    student.ParentName = ParentName;
                    student.ParentSurname = ParentSurname;
                    student.ClassLetter = Convert.ToChar(ClassLetter.ToUpper());
                    student.ClassNumber = NumberConvertor(ClassNumber);
                    student.Class = Appender(ClassLetter, ClassNumber);
                    student.Number = Int32.Parse(Number);
                    student.Age = AgeConvertor(Age);
                    student.Barcode = Barcode;
                    student.ID = 6;
                    student.LastCheckIn = DateTime.Now;
                    student.DateOfCreation = DateTime.Now;

                    //TODO: ADD student to DATABASE
                    FakeStudentDataLayer.Add(student);
                }));
        }
    }
    #endregion
#区域假数据库
私有静态ObservableCollection fakeStudentDataLayer;
公共用户dummydata()
{
fakeStudentDataLayer=新的ObservableCollection()
{
新学生(){Name=“test1”,姓氏=“姓氏test1”,年龄=22岁,条形码=“testbarcode1”,ClassLetter=“A”,ClassNumber=6,ID=1,ParentName=“parentTest1”,ParentName=“parentnamesttitle1”,Number=22,DateOfCreation=newdatetime(2008,12,2),LastCheckIn=newdatetime(2014,3,9)},
新学生(){Name=“test2”,姓氏=“姓氏test2”,年龄=22岁,条形码=“testbarcode2”,ClassLetter=“B”,ClassNumber=8,ID=2,ParentName=“parentTest2”,ParentName=“parentnamesttitle2”,Number=22,DateOfCreation=newdatetime(2008,12,2),LastCheckIn=newdatetime(2014,3,9)},
新学生(){Name=“test3”,姓氏=“姓氏test3”,年龄=22岁,条形码=“testbarcode3”,ClassLetter=“C”,ClassNumber=10,ID=3,ParentName=“parentTest3”,ParentName=“parentnamesttitle3”,Number=22,DateOfCreation=newdatetime(2008,12,2),LastCheckIn=newdatetime(2014,3,9)}
};
}
公共可见收集FakeStudentDataLayer
{
获取{return fakeStudentDataLayer;}
设置{fakeStudentDataLayer=value;RaisePropertyChanged(“fakeStudentDataLayer”);}
}
#端区
#区域命令
私有RelayCommand _addStudentCommand;
公共ICommand NewStudentCommand
{
得到
{
return\u addStudentCommand
??(_addStudentCommand=新的RelayCommand(()=>
{
//创造新的学生
学生=新生();
//设置新学生的属性
//TODO:添加ID值
student.Name=Name;
学生。姓氏=姓氏;
student.ParentName=ParentName;
student.parent姓氏=parent姓氏;
student.ClassLetter=Convert.ToChar(ClassLetter.ToUpper());
student.ClassNumber=NumberConvertor(ClassNumber);
student.Class=Appender(ClassLetter,ClassNumber);
student.Number=Int32.Parse(Number);
学生。年龄=年龄转换器(年龄);
学生。条形码=条形码;
student.ID=6;
student.LastCheckIn=DateTime.Now;
student.DateOfCreation=DateTime.Now;
//TODO:将学生添加到数据库
FakeStudentDataLayer.Add(学生);
}));
}
}
#端区
这是AddView

<Grid>
    <!--DataContext-->
    <Grid.DataContext>
        <dc:UserDummyData/>
    </Grid.DataContext>

    <!--Student TextBoxes-->
    <TextBlock x:Name="StudentNameWaterMark"
               Grid.Column="2"
               Text="{x:Static p:Resources.Name}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding
                    ElementName=StudentNameContentTextBox, 
                    Path=Text.IsEmpty, Converter={StaticResource 
                    WaterMarkRemover}}"/>
    <TextBox x:Name="StudentNameContentTextBox"
             Grid.Column="2"
             Text="{Binding Name}"
             Width="{Binding ElementName=StudentNameWaterMark,
                Path=Width}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent">
    </TextBox>
    <TextBlock Name="StudentSurnameWaterMark"
               Grid.Column="2" Grid.Row="1"
               Text="{x:Static p:Resources.Surname}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding
                    ElementName=StudentSurnameContentTextBox,
                    Path=Text.IsEmpty, Converter={StaticResource 
                    WaterMarkRemover}}"/>
    <TextBox x:Name="StudentSurnameContentTextBox"
             Grid.Column="2" Grid.Row="1"
             Text="{Binding Surname}"
             Width="{Binding ElementName=StudentSurnameWaterMark,
                Path=Width}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent">
    </TextBox>

    <!--Parent TextBoxes-->
    <TextBlock x:Name="ParentNameWaterMark"
               Grid.Column="2" Grid.Row="2"
               Text="{x:Static p:Resources.ParentName}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding 
                    ElementName=ParentNameContentTextBox, 
                    Path=Text.IsEmpty, Converter={StaticResource 
                    WaterMarkRemover}}"/>
    <TextBox x:Name="ParentNameContentTextBox"
             Grid.Column="2" Grid.Row="2"
             Text="{Binding ParentName}"
             Width="{Binding ElementName=ParentNameWaterMark,
                Path=Width}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent">
    </TextBox>
    <TextBlock x:Name="ParentSurnameWaterMark"
               Grid.Column="2" Grid.Row="3"
               Text="{x:Static p:Resources.ParentSurname}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding 
                      ElementName=ParentSurnameContentTextBox, 
                      Path=Text.IsEmpty, Converter={StaticResource 
                      WaterMarkRemover}}"/>
    <TextBox x:Name="ParentSurnameContentTextBox"
             Grid.Column="2" Grid.Row="3"
             Text="{Binding ParentSurname}"
             Width="{Binding ElementName=ParentSurnameWaterMark,
                Path=Width}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent">
    </TextBox>

    <!--Student Details TextBoxes-->
    <TextBlock x:Name="AgeWaterMark"           
               Grid.Column="5"
               Text="{x:Static p:Resources.Age}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding 
                      ElementName=AgeContentTextBox, 
                      Path=Text.IsEmpty, Converter={StaticResource 
                      WaterMarkRemover}}"/>
    <TextBox x:Name="AgeContentTextBox"
             Grid.Column="5"
             Text="{Binding Age}"
             Width="{Binding ElementName=AgeWaterMark,
                Path=Width}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent"/>

    <Grid Grid.Column="5" Grid.Row="1">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto"/>
            </Grid.ColumnDefinitions>
            <TextBlock x:Name="GradeNumberWaterMark"
                       Text="{x:Static p:Resources.GradeNumber}"
                       Style="{StaticResource GradeWaterMarkStyle}"
                       Visibility="{Binding 
                            ElementName=GradeNumberContentTextBox, 
                            Path=Text.IsEmpty, Converter={StaticResource 
                            WaterMarkRemover}}"/>
            <TextBox x:Name="GradeNumberContentTextBox"
                     Width="{Binding ElementName=GradeNumberWaterMark,
                        Path=Width}"
                     Text="{Binding ClassNumber}"
                     Style="{StaticResource TextBoxTextStyle}"
                     Background="Transparent"/>
        </Grid>
        <Grid Grid.Column="5">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto"/>
            </Grid.ColumnDefinitions>
            <TextBlock x:Name="GradeLetterWaterMark"
                       Text="{x:Static p:Resources.GradeLetter}"
                       Style="{StaticResource GradeWaterMarkStyle}"
                       Visibility="{Binding 
                            ElementName=GradeLetterContentTextBox, 
                            Path=Text.IsEmpty, Converter={StaticResource 
                            WaterMarkRemover}}"/>
            <TextBox x:Name="GradeLetterContentTextBox"
                     Width="{Binding ElementName=GradeLetterWaterMark,
                        Path=Width}"
                     Text="{Binding ClassLetter}"
                     Style="{StaticResource TextBoxTextStyle}"
                     Background="Transparent"/>
        </Grid>
    </Grid>

    <TextBlock x:Name="NumberWaterMark"
               Grid.Column="5" Grid.Row="2"
               Text="{x:Static p:Resources.NumberInClass}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding
                    ElementName=NumberContentTextBox, 
                    Path=Text.IsEmpty, Converter={StaticResource 
                    WaterMarkRemover}}"/>
    <TextBox x:Name="NumberContentTextBox"
             Grid.Column="5" Grid.Row="2"  
             Width="{Binding ElementName=NumberWaterMark,
                    Path=Width}"
             Text="{Binding Number}"
             Style="{StaticResource BasicTextBoxTextStyle}"
             Background="Transparent"/>

    <TextBlock x:Name="BarcodeWaterMark"
               Grid.Column="5" Grid.Row="3"
               Text="{x:Static p:Resources.Barcode}"
               Style="{StaticResource WaterMarkStyle}"
               Visibility="{Binding
                    ElementName=BarcodeContentTextBox, 
                    Path=Text.IsEmpty, Converter={StaticResource 
                    WaterMarkRemover}}"/>
    <TextBox x:Name="BarcodeContentTextBox"
             Grid.Column="5" Grid.Row="3"
             Width="{Binding ElementName=BarcodeWaterMark,
                    Path=Width}"
             Text="{Binding Barcode}"
             Style="{StaticResource BarcodeTextBoxTextStyle}"
             Background="Transparent"/>

    <!--Buttons-->
    <Grid Grid.Row="4" Grid.ColumnSpan="6">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <Button Grid.Row="1"
                Content="{x:Static p:Resources.Add}"
                HorizontalAlignment="Left"
                Style="{StaticResource ButtonStyle}"
                Command="{Binding NewStudentCommand}"/>
        <Button Grid.Column="2"
                Content="{x:Static p:Resources.Clear}"
                HorizontalAlignment="Right"
                Style="{StaticResource ButtonStyle}"/>
    </Grid>
</Grid>

这是ShowView

<Grid>
    <!--DataContext-->
    <Grid.DataContext>
        <dc:UserDummyData/>
    </Grid.DataContext> 
    <!--DataGrid-->         
    <DataGrid AutoGenerateColumns="False"
          CanUserAddRows="True"
          CanUserDeleteRows="True"
          ItemsSource="{Binding FakeStudentDataLayer}">
        <DataGrid.Columns>
            <DataGridTextColumn Header="{x:Static p:Resources.sName}"
                                Binding="{Binding Name}"/>
            <DataGridTextColumn Header="{x:Static p:Resources.sSurname}"
                                Binding="{Binding Surname}"/>
            <DataGridTextColumn Header="{x:Static p:Resources.sAge}"
                                Binding="{Binding Age}"/>
            <DataGridTextColumn Header="{x:Static p:Resources.sGrade}"
                                Binding="{Binding Class}"/>
            <DataGridTextColumn Header="{x:Static p:Resources.sNumber}"
                                Binding="{Binding Number}"/>
            <DataGridTextColumn Header="{x:Static p:Resources.LastCheckIn}"
                                Binding="{Binding LastCheckIn}"/>
        </DataGrid.Columns>
    </DataGrid>
</Grid>

注意:如果我将ShowView中的代码放在AddView中,那么一切都正常,但是如果它们是这样的-一个两个独立的视图,DataGrid不会更新


编辑:我尝试使用相同的结构制作一个更简单的项目。令人难以置信的是,它起了作用,我并没有在这方面做出任何改变。新的sampler项目和这个项目的区别在于我使用了更基本的模型——只有两个属性。如果这很重要的话,我没有本地化。所以我的问题是,为什么它在一个较小的项目上工作,而不是在这个项目上

强制更新到底是什么意思?如果您的意思是添加数据,请尝试使用脚手架


我不确定您的代码到底是什么样子的,但我认为您有一个包含多个视图的窗口,您的窗口有一个MainViewModel,例如,其中的视图有自己的ViewModel。 如果MainViewModel创建并处理其他视图,那么它将获得这些视图的实例,并且能够在那里调用方法

所以,您的问题可能是想知道如何在viewmodels之间进行通信

这是我想到的一个小例子。 如果您有MainViewModel、DataAddViewModel和ShowViewModel。 MainViewModel创建DataAddViewModel和ShowViewModel。 DataAddViewModel有一个事件,该事件在插入新数据时触发。 ShowViewModel有一个到Listview或任何东西的绑定,以及一个触发该绑定的公共方法

注意:下面只是一个例子

数据添加视图模型中可能出现的事件

MainViewModel中可能的事件注册和处理

ShowViewModel中的公共方法


我最好的猜测是,问题来自于您使用了两个独立的
UserDummyData
实例。在“显示”视图和“添加”视图中,您可以如下设置
DataContext

<Grid.DataContext>
    <dc:UserDummyData/>
</Grid.DataContext> 
<Grid ... DataContext="{x:Static p:Resources.MyUserDummyDataInstance}"/>
然后,当您将学生添加到一个
UserDummyData
中时,两个视图都将显示新学生,因为他们的两个列表(其中
public void DataAdded(){
    RaisePropertyChanged("NameOfMyBinding");
}
<Grid.DataContext>
    <dc:UserDummyData/>
</Grid.DataContext> 
<Grid ... DataContext="{x:Static p:Resources.MyUserDummyDataInstance}"/>