windows phone 了解LinearGradientBrush类和RadialGradienBrush类(11)

我们了解到在能在xaml中完成的设计，一般在隐藏文件中也可通过代码完成；本节中的案例是实现对同一设计效果的不同写法；例如在隐藏文件中代码如下：

View Code

using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Animation;

using System.Windows.Shapes;

using Microsoft.Phone.Controls;

namespace LinearGB

{

    public partial class MainPage : PhoneApplicationPage

    {

        // 构造函数

        public MainPage()

        {

            InitializeComponent();

            Init();

        }

        private void Init()

            TextBlock tb = new TextBlock();

            tb.Name = "tbName";

            tb.Text = "显示颜色";

            tb.VerticalAlignment = VerticalAlignment.Center;

            tb.HorizontalAlignment = HorizontalAlignment.Center;

            //实例化

            //LinearGradientBrush lgb1 = new LinearGradientBrush();

            LinearGradientBrush lgb2 = new LinearGradientBrush();

            GradientStopCollection gsc = new GradientStopCollection();

            //设置过渡点的颜色和偏移量

            GradientStop gt1 = new GradientStop();

            //Color c = new Color();

            //c.R = 255;

            //c.A = 230;

            //c.G = 22;

            //c.B = 43;

            //gt1.Color=c;

            gt1.Color = Color.FromArgb(255, 164, 143, 112);

            gt1.Offset = 0.2;

            gsc.Add(gt1);

            GradientStop gt2 = new GradientStop();

            //Color c2 = new Color();

            //c2.R = 251;

            //c2.A = 231;

            //c2.G = 12;

            //c2.B = 13;

            //gt2.Color = c2;

            gt2.Color = Color.FromArgb(229, 178, 234, 188);

            gt2.Offset = 0.7;

            gsc.Add(gt2);

            //设置线性渐变色的起始坐标

            Point p1 = new Point(0, 0);

            lgb2.StartPoint = p1;

            //设置线性渐变色的终止坐标

            Point p2 = new Point(1, 1);

            lgb2.EndPoint = p2;

            //设置渐变停止点

            lgb2.GradientStops = gsc;

            //设置前景色

            tb.Foreground = lgb2;

            ContentPanel.Children.Add(tb);

}

 上面代码实现的效果：

 从xaml文件中同样也可以实现类似的效果，ContentPanel下的textblock内容如下:

<TextBlock x:Name="tbName" Text="显示颜色" VerticalAlignment="Center" HorizontalAlignment="Center" >

                <TextBlock.Foreground>

                    <LinearGradientBrush StartPoint="0 0" EndPoint="1 1">

                        <LinearGradientBrush.GradientStops>

                        <GradientStopCollection>

                            <GradientStop Offset="0.2" Color="AliceBlue"></GradientStop>

                            <GradientStop Offset="0.7" Color="Brown"></GradientStop>

                        </GradientStopCollection>

                         </LinearGradientBrush.GradientStops>

                    </LinearGradientBrush>

                </TextBlock.Foreground>

            </TextBlock>

 实现的效果：

官方解释

下图演示对角渐变。 其中添加了一条线，用于突出显示渐变从起点到终点的内插路径。

对角方向的线性渐变

下一幅插图显示的是同一线性渐变，但它具有突出显示的渐变停止点。

具有突出显示的渐变停止点的对角线性渐变

<TextBlock x:Name="tbRadia" VerticalAlignment="Center"  HorizontalAlignment="Center" Text="扩散式辐射">

                     <RadialGradientBrush GradientOrigin="0.5,0.5" Center="0.5,0.5"

        RadiusX="0.5" RadiusY="0.5">

        <GradientStop Color="Yellow" Offset="0" />

        <GradientStop Color="Red" Offset="0.25" />

        <GradientStop Color="Blue" Offset="0.75" />

        <GradientStop Color="LimeGreen" Offset="1" />

      </RadialGradientBrush>

 效果图：

径向渐变中的渐变停止点

本文转自shenzhoulong  51CTO博客，原文链接：http://blog.51cto.com/shenzhoulong/835534，如需转载请自行联系原作者