Question

我正在编辑用于桌面/移动应用程序的VS2005中用C＃编写的旧程序。

在移动应用程序上，我仅限于使用.NET Compact Framework 3.1，因此我发现很难实现通常非常简单的事情。

我希望树状菜单的某些区域显示为灰色/禁用。这背后的原因是客户端可以拥有该应用程序的三个不同版本之一;精简，全面和亲。

如果客户端正在使用该产品的精简版本，我希望精简版本缺少灰色的选项，这样客户端就能看到它们缺少的内容。目前我仅限于让他们看不到不可用的选项。

简单地说，有没有一种方法可以在.NET compact framework 3.1的约束下实现这一点？

感谢。

Answer 1

你可以从TreeView和TreeNode中实现这些类，并实现这种行为。

   using System;
using System.Linq;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace SmartDeviceProject3
{
    public partial class Form1 : Form
    {

        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;
        private System.Windows.Forms.MainMenu mainMenu1;
        private TreeViewEx treeView1;

        public Form1()
        {
            this.mainMenu1 = new System.Windows.Forms.MainMenu();
            this.treeView1 = new TreeViewEx();

            this.SuspendLayout();
            this.treeView1.Dock = System.Windows.Forms.DockStyle.Fill;
            this.treeView1.Location = new System.Drawing.Point(0, 0);
            this.treeView1.Name = "treeView1";
            this.treeView1.Size = new System.Drawing.Size(240, 268);
            this.treeView1.TabIndex = 0;
            this.AutoScaleDimensions = new System.Drawing.SizeF(96F, 96F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Dpi;
            this.AutoScroll = true;
            this.ClientSize = new System.Drawing.Size(240, 268);
            this.Controls.Add(this.treeView1);
            this.Menu = this.mainMenu1;
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);

        }

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);

            treeView1.Nodes.Add(new TreeViewNodeEx()
            {
                Text = "Enabled"
            });
            treeView1.Nodes.Add(new TreeViewNodeEx()
            {
                Text = "Disabled",
                Enabled = false,
            });
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

    }

    public class TreeViewEx 
        : TreeView
    {
        protected override void OnAfterSelect(TreeViewEventArgs e)
        {
            var node = e.Node as TreeViewNodeEx;
            if (node != null && !node.Enabled)
            {
                return;
            }
            base.OnAfterSelect(e);
        }
    }

    public class TreeViewNodeEx 
        : TreeNode
    {
        private bool _enabled = true;
        public bool Enabled
        {
            get
            {
                return _enabled;
            }
            set
            {
                if (_enabled != value)
                {
                    _enabled = value;
                    if (_enabled)
                    {
                        this.ForeColor = Color.Black;
                    }
                    else
                    {
                        this.ForeColor = Color.Gray;
                    }
                }
            }
        }

    }
}

带有灰色/禁用文本的树状菜单，具有紧凑的框架限制

1 个答案: