Visão geral de ListView
The ListView control provides the infrastructure to display a set of data items in different layouts or views. For example, a user may want to display data items in a table and also to sort its columns.
Este tópico contém as seguintes seções.
- What Is a ListView?
- Defining a View Mode for a ListView
- Binding Data to a ListView
- Styling a ListView That Implements a GridView
- Sharing the Same View Mode
- Creating a Custom View Mode
- Tópicos relacionados
What Is a ListView?
The ListView control is an ItemsControl that is derived from ListBox. Typically, its items are members of a data collection and are represented as ListViewItem objects. A ListViewItem is a ContentControl and can contain only a single child element. However, that child element can be any visual element.
Defining a View Mode for a ListView
To specify a view mode for the content of a ListView control, you set the View property. One view mode that Windows Presentation Foundation (WPF) provides is GridView, which displays a collection of data items in a table that has customizable columns.
The following example shows how to define a GridView for a ListView control that displays employee information.
<ListView ItemsSource="{Binding Source=
{StaticResource EmployeeInfoDataSource}}">
<ListView.View>
<GridView AllowsColumnReorder="true"
ColumnHeaderToolTip="Employee Information">
<GridViewColumn DisplayMemberBinding=
"{Binding Path=FirstName}"
Header="First Name" Width="100"/>
<GridViewColumn DisplayMemberBinding=
"{Binding Path=LastName}"
Width="100">
<GridViewColumnHeader>Last Name
<GridViewColumnHeader.ContextMenu>
<ContextMenu MenuItem.Click="LastNameCM_Click"
Name="LastNameCM">
<MenuItem Header="Ascending" />
<MenuItem Header="Descending" />
</ContextMenu>
</GridViewColumnHeader.ContextMenu>
</GridViewColumnHeader>
</GridViewColumn>
<GridViewColumn DisplayMemberBinding=
"{Binding Path=EmployeeNumber}"
Header="Employee No." Width="100"/>
</GridView>
</ListView.View>
</ListView>
The following illustration shows how the data appears for the previous example.
.jpg "ListView com saída de GridView")
You can create a custom view mode by defining a class that inherits from the ViewBase class. The ViewBase class provides the infrastructure that you need to create a custom view. For more information about how to create a custom view, see Como: Criar um Modo de Visualização Personalizado para um ListView.
Binding Data to a ListView
Use the Items and ItemsSource properties to specify items for a ListView control. The following example sets the ItemsSource property to a data collection that is called EmployeeInfoDataSource.
<ListView ItemsSource="{Binding Source=
{StaticResource EmployeeInfoDataSource}}">
In a GridView, GridViewColumn objects bind to specified data fields. The following example binds a GridViewColumn object to a data field by specifying a Binding for the DisplayMemberBinding property.
Dim gvc1 As New GridViewColumn()
gvc1.DisplayMemberBinding = New Binding("FirstName")
gvc1.Header = "FirstName"
gvc1.Width = 100
GridViewColumn gvc1 = new GridViewColumn();
gvc1.DisplayMemberBinding = new Binding("FirstName");
gvc1.Header = "FirstName";
gvc1.Width = 100;
<GridViewColumn DisplayMemberBinding=
"{Binding Path=FirstName}"
Header="First Name" Width="100"/>
You can also specify a Binding as part of a DataTemplate definition that you use to style the cells in a column. In the following example, the DataTemplate that is identified with a ResourceKey sets the Binding for a GridViewColumn. Note that this example does not define the DisplayMemberBinding because doing so overrides the binding that is specified by DataTemplate.
<DataTemplate x:Key="myCellTemplateMonth">
<DockPanel>
<TextBlock Foreground="DarkBlue" HorizontalAlignment="Center">
<TextBlock.Text>
<Binding Path="Month"/>
</TextBlock.Text>
</TextBlock>
</DockPanel>
</DataTemplate>
<GridViewColumn Header="Month" Width="80"
CellTemplate="{StaticResource myCellTemplateMonth}"/>
Styling a ListView That Implements a GridView
The ListView control contains ListViewItem objects, which represent the data items that are displayed. You can use the following properties to define the content and style of data items:
On the ListView control, use the ItemTemplate, ItemTemplateSelector, and ItemContainerStyle properties.
On the ListViewItem control, use the ContentTemplate and ContentTemplateSelector properties.
To avoid alignment issues between cells in a GridView, do not use the ItemContainerStyle to set properties or add content that affects the width of an item in a ListView. For example, an alignment issue can occur when you set the Margin property in the ItemContainerStyle. To specify properties or define content that affects the width of items in a GridView, use the properties of the GridView class and its related classes, such as GridViewColumn.
For more information about how to use GridView and its supporting classes, see GridView Overview.
If you define an ItemContainerStyle for a ListView control and also define an ItemTemplate, you must include a ContentPresenter in the style in order for the ItemTemplate to work correctly.
Do not use the HorizontalContentAlignment and VerticalContentAlignment properties for ListView content that is displayed by using a GridView. To specify the alignment of content in a column of a GridView, define a CellTemplate.
Sharing the Same View Mode
Two ListView controls cannot share the same view mode at the same time. If you try to use the same view mode with more than one ListView control, an exception occurs.
To specify a view mode that can be simultaneously used by more than one ListView, use templates or styles. Para obter um exemplo de como definir modos de exibição como Resources, consulte ListView com vários exemplos de modos de exibição.
Creating a Custom View Mode
Customized views like GridView are derived from the ViewBase abstract class, which provides the tools to display data items that are represented as ListViewItem objects.
Para obter um exemplo de um modo de exibição personalizado, consulte ListView com vários exemplos de modos de exibição.
Consulte também
Referência
Conceitos
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