模板描述控件的整体外观和视觉外观.对于每个控件,都有一个与之关联的默认模板,它为控件提供了外观.在WPF应用程序中,当您想要自定义控件的可视行为和视觉外观时,可以轻松创建自己的模板.
逻辑和模板之间的连接可以通过数据绑定实现. 样式和模板之间的主要区别列在下面和下面;
样式只能使用该控件的默认属性更改控件的外观.
使用模板,您可以访问控件的更多部分而不是样式.您还可以指定控件的现有行为和新行为.
有两种类型的模板最常用和减去;
控制模板
数据模板
控制模板定义控件的可视外观.所有UI元素都具有某种外观和行为,例如,Button具有外观和行为.单击事件或鼠标悬停事件是响应单击和悬停而触发的行为,还有一个默认的按钮外观,可以通过控制模板进行更改.
我们举一个简单的例子.我们将创建两个按钮(一个是模板,另一个是默认按钮)并用一些属性初始化它们.
<Window x:Class = "TemplateDemo.MainWindow" xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml" Title = "MainWindow" Height = "350" Width = "604"> <Window.Resources> <ControlTemplate x:Key = "ButtonTemplate" TargetType = "Button"> <Grid> <Ellipse x:Name = "ButtonEllipse" Height = "100" Width = "150" > <Ellipse.Fill> <LinearGradientBrush StartPoint = "0,0.2" EndPoint = "0.2,1.4"> <GradientStop Offset = "0" Color = "Red" /> <GradientStop Offset = "1" Color = "Orange" /> </LinearGradientBrush> </Ellipse.Fill> </Ellipse> <ContentPresenter Content = "{TemplateBinding Content}" HorizontalAlignment = "Center" VerticalAlignment = "Center" /> </Grid> <ControlTemplate.Triggers> <Trigger Property = "IsMouseOver" Value = "True"> <Setter TargetName = "ButtonEllipse" Property = "Fill" > <Setter.Value> <LinearGradientBrush StartPoint = "0,0.2" EndPoint = "0.2,1.4"> <GradientStop Offset = "0" Color = "YellowGreen" /> <GradientStop Offset = "1" Color = "Gold" /> </LinearGradientBrush> </Setter.Value> </Setter> </Trigger> <Trigger Property = "IsPressed" Value = "True"> <Setter Property = "RenderTransform"> <Setter.Value> <ScaleTransform ScaleX = "0.8" ScaleY = "0.8" CenterX = "0" CenterY = "0" /> </Setter.Value> </Setter> <Setter Property = "RenderTransformOrigin" Value = "0.5,0.5" /> </Trigger> </ControlTemplate.Triggers> </ControlTemplate> </Window.Resources> <StackPanel> <Button Content = "Round Button!" Template = "{StaticResource ButtonTemplate}" Width = "150" Margin = "50" /> <Button Content = "Default Button!" Height = "40" Width = "150" Margin = "5" /> </StackPanel> </Window>
编译并执行上述代码时,它将显示以下MainWindow.
当您使用自定义模板将鼠标移到按钮上时,它将更改其颜色,如下所示.
数据模板定义并指定数据集合的外观和结构.它提供了在任何UI元素上格式化和定义数据表示的灵活性.它主要用于与数据相关的Item控件,如ComboBox,ListBox等.
让我们举一个简单的例子来理解数据模板的概念.创建一个名为 WPFDataTemplates 的新WPF项目.
在以下XAML代码中,我们将创建一个数据模板作为资源持有标签和文本框.还有一个按钮和一个列表框来显示数据.
<Window x:Class = "WPFDataTemplates.MainWindow" xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d = "http://schemas.microsoft.com/expression/blend/2008" xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local = "clr-namespace:WPFDataTemplates" xmlns:loc = "clr-namespace:WPFDataTemplates" mc:Ignorable = "d" Title = "MainWindow" Height = "350" Width = "525"> <Window.Resources> <DataTemplate DataType = "{x:Type loc:Person}"> <Grid> <Grid.RowDefinitions> <RowDefinition Height = "Auto" /> <RowDefinition Height = "Auto" /> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width = "Auto" /> <ColumnDefinition Width = "200" /> </Grid.ColumnDefinitions> <Label Name = "nameLabel" Margin = "10"/> <TextBox Name = "nameText" Grid.Column = "1" Margin = "10" Text = "{Binding Name}"/> <Label Name = "ageLabel" Margin = "10" Grid.Row = "1"/> <TextBox Name = "ageText" Grid.Column = "1" Grid.Row = "1" Margin = "10" Text = "{Binding Age}"/> </Grid> </DataTemplate> </Window.Resources> <Grid> <Grid.RowDefinitions> <RowDefinition Height = "Auto" /> <RowDefinition Height = "*" /> </Grid.RowDefinitions> <ListBox ItemsSource = "{Binding}" /> <StackPanel Grid.Row = "1" > <Button Content = "_Show..." Click = "Button_Click" Width = "80" HorizontalAlignment = "Left" Margin = "10"/> </StackPanel> </Grid> </Window>
这是在C#中的实现,其中Person对象的列表被分配给DataContext,Person类的实现和按钮点击事件.
using System.Collections.Generic; using System.Windows; namespace WPFDataTemplates { public partial class MainWindow : Window { Person src = new Person { Name = "Ali", Age = 27 }; List<Person> people = new List<Person>(); public MainWindow() { InitializeComponent(); people.Add(src); people.Add(new Person { Name = "Mike", Age = 62 }); people.Add(new Person { Name = "Brian", Age = 12 }); this.DataContext = people; } private void Button_Click(object sender, RoutedEventArgs e) { string message = src.Name + " is " + src.Age; MessageBox.Show(message); } } public class Person { private string nameValue; public string Name { get { return nameValue; } set { nameValue = value; } } private double ageValue; public double Age { get { return ageValue; } set { if (value != ageValue) { ageValue = value; } } } } }
编译时并执行上面的代码,它将生成以下窗口.它包含一个列表,在列表框内,每个列表框项包含显示在标签和文本框上的Person类对象数据.