Question

我在MSDN上做了关于如何创建自定义控件的教程

http://msdn.microsoft.com/en-us/library/cc295235(v=expression.30).aspx

我在尝试在按钮上显示默认图像时遇到了问题。

以下是代码：

using System;
using System.Collections.Generic;
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.Shapes;
using System.ComponentModel;

namespace ControlTest
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    public MainWindow()
    {
        this.InitializeComponent();


    }

}
[Description("Represents a custom button control that responds to a Click event. Displays an image using a custom Source property if the Source property is bound to an Image in the template.")]
public class ImageButton : Button 
{ 
    [Description("The image displayed in the button if there is an Image control in the template whose Source property is template-bound to the ImageButton Source property."), Category("Common Properties")] 
    public ImageSource Source 
    { 
        get { return base.GetValue(SourceProperty) as ImageSource; } 
        set { base.SetValue(SourceProperty, value); } 
    } 
    public static readonly DependencyProperty SourceProperty = 
        DependencyProperty.Register("Source", typeof(ImageSource), typeof(ImageButton)); 

    // Constructor:  
    public ImageButton()  
    {  
    if (DesignerProperties.GetIsInDesignMode(this))  
    {  
        this.Source = new BitmapImage(new Uri("images/Image.png", UriKind.Relative));  
        }  
    }  


}

}

感谢您的帮助！ =）

Answer 1

当您声明DependencyProperty时，您可以为其指定默认值，如下所示：

public static readonly DependencyProperty SourceProperty =
            DependencyProperty.Register("Source", typeof (ImageSource), typeof (ImageButton), new PropertyMetadata("images/Image.png"));

DependencyProperty.Register的最后一个参数是PropertyMetadata，可用于指定默认ImageSource。我希望这会有所帮助。

在Custom Control帮助上显示默认图像？ MSDN教程

1 个答案: