无废话WPF系列15：样式

样式很好理解，就像CSS里的一样，无需多加解释

1. 样式中的Setter

使用示例：

<Window x:Class="DeepXAML.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DeepXAML"       
        xmlns:sys="clr-namespace:System;assembly=mscorlib"
        Title="MainWindow" Height="250" Width="450">
    <Window.Resources>
        <Style TargetType="Button">
            <Setter Property="FontSize" Value="30"></Setter>
            <Setter Property="Margin" Value="10"></Setter>
        </Style>
    </Window.Resources>       
    <StackPanel>
        <Button>New</Button>
        <Button>Save</Button>
        <Button>Exit</Button>
    </StackPanel>
</Window>

很明显，使用样式让我们代码更精简，而且界面的外观可以集中处理。

2. 样式中的Trigger

当某些条件满足时，触发一个行为

a. 基本Trigger

<Window x:Class="DeepXAML.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DeepXAML"       
        xmlns:sys="clr-namespace:System;assembly=mscorlib"
        Title="MainWindow" Height="250" Width="450">
    <Window.Resources>
        <Style TargetType="CheckBox">
            <Setter Property="FontSize" Value="30"></Setter>
            <Setter Property="Margin" Value="10"></Setter>
            <Style.Triggers>
                <Trigger Property="IsChecked" Value="true">
                    <Trigger.Setters>
                        <Setter Property="Foreground"  Value="Red"></Setter>
                    </Trigger.Setters>
                </Trigger>    
            </Style.Triggers>
        </Style>
    </Window.Resources>       
    <StackPanel>
        <CheckBox>.Net</CheckBox>
        <CheckBox>Java</CheckBox>
        <CheckBox>Ruby</CheckBox>
        <CheckBox>Python</CheckBox>
    </StackPanel>
</Window>

b. MultiTrigger

<Window x:Class="DeepXAML.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DeepXAML"       
        xmlns:sys="clr-namespace:System;assembly=mscorlib"
        Title="MainWindow" Height="250" Width="450">
    <Window.Resources>
        <Style TargetType="CheckBox">
            <Setter Property="FontSize" Value="30"></Setter>
            <Setter Property="Margin" Value="10"></Setter>
            <Style.Triggers>
                <MultiTrigger>
                    <MultiTrigger.Conditions>
                        <Condition Property="IsChecked" Value="true"></Condition>
                        <Condition Property="Content" Value="Java"></Condition>
                    </MultiTrigger.Conditions>
                    <MultiTrigger.Setters>
                        <Setter Property="Foreground" Value="Red"></Setter>
                    </MultiTrigger.Setters>
                </MultiTrigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>       
    <StackPanel>
        <CheckBox>.Net</CheckBox>
        <CheckBox>Java</CheckBox>
        <CheckBox>Ruby</CheckBox>
        <CheckBox>Python</CheckBox>
    </StackPanel>
</Window>

c. DataTrigger

<Window x:Class="DeepXAML.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DeepXAML"       
        xmlns:sys="clr-namespace:System;assembly=mscorlib"
        Title="MainWindow" Height="250" Width="450">
    <Window.Resources>
        <Style TargetType="TextBox">
            <Setter Property="Margin" Value="10"></Setter>
            <Style.Triggers>
                <DataTrigger Binding="{Binding Path=Name}" Value="Jack">
                    <Setter Property="Foreground" Value="Red"></Setter>
                </DataTrigger>               
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <StackPanel x:Name="stackPanel">
        <TextBox Text="{Binding Path=Name}"></TextBox>
        <TextBox Text="{Binding Path=Age}"></TextBox>
        <TextBox></TextBox>
    </StackPanel>
</Window>

public MainWindow()
{
    InitializeComponent();

    Person p = new Person { Name = "Jack", Age = 30 };
    this.stackPanel.DataContext = p;            
}

public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
}

d. 多数据条件的trigger

MultiDataTrigger这个类似上面的MultiTrigger,不用细说了。

e. EventTrigger

是由事件来触发

<Window x:Class="DeepXAML.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DeepXAML"       
        xmlns:sys="clr-namespace:System;assembly=mscorlib"
        Title="MainWindow" Height="250" Width="450">
    <Window.Resources>
        <Style TargetType="Button">
            <Setter Property="Margin" Value="10"></Setter>
            <Style.Triggers>
                <EventTrigger RoutedEvent="MouseEnter">
                    <BeginStoryboard>
                        <Storyboard>                            
                            <DoubleAnimation To="20" Duration="0:0:0.2" Storyboard.TargetProperty="Width"></DoubleAnimation>
                            <DoubleAnimation To="70" Duration="0:0:0.2" Storyboard.TargetProperty="Height"></DoubleAnimation>
                        </Storyboard>
                    </BeginStoryboard>
                </EventTrigger>
                <EventTrigger RoutedEvent="MouseLeave">
                    <BeginStoryboard>
                        <Storyboard>
                            <DoubleAnimation To="100" Duration="0:0:0.2" Storyboard.TargetProperty="Width"></DoubleAnimation>
                            <DoubleAnimation To="20" Duration="0:0:0.2" Storyboard.TargetProperty="Height"></DoubleAnimation>
                        </Storyboard>
                    </BeginStoryboard>
                </EventTrigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <StackPanel x:Name="stackPanel">
        <Button Width="100" Height="20">OK</Button>
    </StackPanel>
</Window>

这里DoubleAnimation必须显示设置Button的Width和Height,不能是用默认的，否则会报错。