WPFLoading遮层罩 - 山涧清泉

一直想实现这么个功能来着，所以去网上搜了资料，复杂的看不懂，后来挑了一个最简单的，复用了这位大神的很多代码（大神看到了别打脸）。这位大神是用UserControl，使用时则是调用用户控件中的方法。之前有用过Telerik的RadBusyIndicator,感觉很好，它是将要遮罩部分直接以内容的形式包裹在RadBusyIndicator的Content属性中，使用时就更简单了，IsBusy=true时遮层罩开启，IsBusy=false遮层罩关闭/隐藏。一为了实现起来不复杂，二为了实现RadBusyIndicator的用法，实现自己的自定义控件，所以才有了这篇文章，先上效果图

接下来先上自定义控件前台代码：

下面的是自定义控件的后台逻辑和依赖属性：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Threading;

namespace MyBusyIndicator
{
    /// <summary>
    /// 按照步骤 1a 或 1b 操作，然后执行步骤 2 以在 XAML 文件中使用此自定义控件。
    ///
    /// 步骤 1a) 在当前项目中存在的 XAML 文件中使用该自定义控件。
    /// 将此 XmlNamespace 特性添加到要使用该特性的标记文件的根
    /// 元素中:
    ///
    ///     xmlns:MyNamespace="clr-namespace:MyBusyIndicator"
    ///
    ///
    /// 步骤 1b) 在其他项目中存在的 XAML 文件中使用该自定义控件。
    /// 将此 XmlNamespace 特性添加到要使用该特性的标记文件的根
    /// 元素中:
    ///
    ///     xmlns:MyNamespace="clr-namespace:MyBusyIndicator;assembly=MyBusyIndicator"
    ///
    /// 您还需要添加一个从 XAML 文件所在的项目到此项目的项目引用，
    /// 并重新生成以避免编译错误:
    ///
    ///     在解决方案资源管理器中右击目标项目，然后依次单击
    ///     “添加引用”->“项目”->[浏览查找并选择此项目]
    ///
    ///
    /// 步骤 2)
    /// 继续操作并在 XAML 文件中使用控件。
    ///
    ///     <MyNamespace:BusyIndicator/>
    ///
    /// </summary>
    public class BusyIndicator : Control
    {
        private readonly DispatcherTimer animationTimer;

public static readonly DependencyProperty IsBusyProperty;

        public static readonly DependencyProperty ContentProperty;
        static BusyIndicator()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(BusyIndicator), new FrameworkPropertyMetadata(typeof(BusyIndicator)));

IsBusyProperty = DependencyProperty.Register("IsBusy", typeof(bool), typeof(BusyIndicator), new PropertyMetadata(false, new PropertyChangedCallback(OnBusyChanged)));

ContentProperty = DependencyProperty.Register("Content", typeof(object), typeof(BusyIndicator));
}

        public bool IsBusy
        {
            get { return (bool)GetValue(IsBusyProperty); }
            set { SetValue(IsBusyProperty, value); }
        }

        public object Content
        {
            get { return GetValue(ContentProperty); }
            set { SetValue(ContentProperty, value); }
        }

        private static void OnBusyChanged(DependencyObject sender,DependencyPropertyChangedEventArgs e)
        {
            BusyIndicator indicator = sender as BusyIndicator;
            if ((bool)e.NewValue == true)
            {
                indicator.Start();
            }
            else
            {
                indicator.Stop();
            }
        }

        public BusyIndicator()
        {
            animationTimer = new DispatcherTimer(
                DispatcherPriority.ContextIdle, Dispatcher);
            animationTimer.Interval = new TimeSpan(0, 0, 0, 0, 90);
        }
        #region Private Methods
        private void Start()
        {
            if (this.IsInitialized)
            {
                Border border = GetTemplateChild("PART_Border") as Border;
                border.Visibility = Visibility.Visible;
                Grid grid = GetTemplateChild("PART_LayoutRoot") as Grid;
                grid.Visibility = Visibility.Visible;
                animationTimer.Tick += HandleAnimationTick;
                animationTimer.Start();
            }

        }

        private void Stop()
        {
            if (this.IsInitialized)
            {
                Border border = GetTemplateChild("PART_Border") as Border;
                Grid grid = GetTemplateChild("PART_LayoutRoot") as Grid;
                border.Visibility = Visibility.Hidden;
                grid.Visibility = Visibility.Hidden;
                animationTimer.Stop();
                animationTimer.Tick -= HandleAnimationTick;
            }
        }

        private void HandleAnimationTick(object sender, EventArgs e)
        {
            RotateTransform SpinnerRotate = GetTemplateChild("PART_SpinnerRotate") as RotateTransform;
            SpinnerRotate.Angle = (SpinnerRotate.Angle + 36) % 360;
        }

        private void SetPosition(Ellipse ellipse, double offset,
            double posOffSet, double step)
        {
            ellipse.SetValue(Canvas.LeftProperty, 50.0
                + Math.Sin(offset + posOffSet * step) * 50.0);

            ellipse.SetValue(Canvas.TopProperty, 50
                + Math.Cos(offset + posOffSet * step) * 50.0);
        }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

const double offset = Math.PI;
const double step = Math.PI * 2 / 10.0;

            Ellipse C0 = GetTemplateChild("PART_C0") as Ellipse;
            Ellipse C1 = GetTemplateChild("PART_C1") as Ellipse;
            Ellipse C2 = GetTemplateChild("PART_C2") as Ellipse;
            Ellipse C3 = GetTemplateChild("PART_C3") as Ellipse;
            Ellipse C4 = GetTemplateChild("PART_C4") as Ellipse;
            Ellipse C5 = GetTemplateChild("PART_C5") as Ellipse;
            Ellipse C6 = GetTemplateChild("PART_C6") as Ellipse;
            Ellipse C7 = GetTemplateChild("PART_C7") as Ellipse;
            Ellipse C8 = GetTemplateChild("PART_C8") as Ellipse;

            SetPosition(C0, offset, 0.0, step);
            SetPosition(C1, offset, 1.0, step);
            SetPosition(C2, offset, 2.0, step);
            SetPosition(C3, offset, 3.0, step);
            SetPosition(C4, offset, 4.0, step);
            SetPosition(C5, offset, 5.0, step);
            SetPosition(C6, offset, 6.0, step);
            SetPosition(C7, offset, 7.0, step);
            SetPosition(C8, offset, 8.0, step);

            if (this.IsBusy)
            {
                this.Start();
            }
            else
            {
                this.Stop();
            }
        }

#endregion
}
}

以上便是全部控件的代码了，为了能够使用它，我将他单独编译成了一个dll，下面是如何使用该控件的例子，前台代码如下：

记得注意引用的命名空间和程序集，下面是后台代码：

namespace CustomControls
{
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            busy.IsBusy = !busy.IsBusy;
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            busy.IsBusy = true;
        }
    }
}

OK，全部代码都已上。简单的说一句，不怎么会使用CSDN，不知道怎么插入代码，所以只好选择全部复制，一个很简单的控件。

发表于 2018-03-01 16:02 山涧清泉阅读(350) 评论(0) 编辑收藏举报