TagCloud.cs

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

namespace TagControls
{
    [System.ComponentModel.DefaultEvent("TagSelected")]
    public partial class TagCloud : UserControl
    {
        private List<TagInfo> tags = new List<TagInfo>();
        private string selectedTag;
        private string username;
        private bool showMyTagsOnly;
        private SortOrder sortBy;
        private Single mintagsize = 5.0F;
        private Single maxsize = 20.0F;
        private List<TagsInfo> tagslist = new List<TagsInfo>();

        public event TagCloudEventHandler TagSelected;

        public TagCloud()
        {
            InitializeComponent();
        }

        [
            TypeConverter(typeof(TagCloud)),
            Category("Appearance"),
            Description("The current user's username")
        ]
        public string Username
        {
            get { return username; }
            set { username = value; }
        }
        public Single minTagSize
        {
            get { return mintagsize; }
            set { mintagsize = value;}
        }

        public Single maxTagSize
        {
            get { return maxsize; }
            set { maxsize = value; }
        } 
        [
            TypeConverter(typeof(TagCloud)),
            Category("Appearance"),
            Description("The library tags to work from")
        ]
        public List<TagInfo> Tags
        {
            get { return tags; }
            set { tags = value; Updater(); }
        }

        [
            TypeConverter(typeof(TagCloud)),
            Category("Appearance"),
            Description("The currently selected tag")
        ]
        public string SelectedTag
        {
            get { return selectedTag; }
            set { selectedTag = value; }
        }

        [
            TypeConverter(typeof(TagCloud)),
            Category("Appearance"),
            Description("Wether to show only the current user's tags")
        ]
        public bool ShowMyTagsOnly
        {
            get { return showMyTagsOnly; }
            set
            {
                showMyTagsOnly = value;
                chkOnlyMine.Checked = value;
            }
        }

        public enum SortOrder
        {
            Alphabetical,
            Size
        }

        public SortOrder SortBy
        {
            get { return sortBy; }
            set
            {
                sortBy = value;
                if (value == SortOrder.Alphabetical)
                    chkAlphabetical.Checked = true;
                else
                    chkBySize.Checked = true;
            }
        }

        private void SortTags()
        {
            //sort input tags efter navn
            Sorter.AlphabeticalSortTags(tags);

            //Add user and weight info the the tags
            Sorter.WeightAndGroupTags(tags, tagslist, username);
   
            if (sortBy == SortOrder.Size)
            {
                Sorter.WeightSortTags(tagslist);
            }
        }

        private void RenderCloud()
        {
            this.SuspendLayout();
            flowLayoutPanel.Controls.Clear();
                       
            if (tagslist.Count == 0)
            {
                  // Show a greyed out text in the middle of the canvas,
                 //  telling the user there are no tags... New users
                //   who turn on "Show only my tags" will need this information

                Label NoTags = new System.Windows.Forms.Label();
                NoTags.Location = new System.Drawing.Point(0, 0);
                NoTags.Name = "NoTags";
                NoTags.Text = "No tags.";
                NoTags.AutoSize = true;
                NoTags.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
                NoTags.ForeColor = System.Drawing.SystemColors.GrayText;
                NoTags.Font = new System.Drawing.Font("Microsoft Sans Serif", maxsize);

                flowLayoutPanel.Controls.Add(NoTags);
            }
            else
            {
                Single TagSize;
                // Code which renders the actual tag cloud...

                foreach (TagsInfo tag in tagslist)
                {
                    if (showMyTagsOnly == false)
                    {
                        LinkLabel lilTagCloud = new LinkLabel();
                        lilTagCloud.AutoSize = true;

                        TagSize = Convert.ToSingle(tag.Weight) / 100.0F * maxsize + mintagsize;

                        lilTagCloud.Font = new System.Drawing.Font("Microsoft Sans Serif", TagSize);
                        lilTagCloud.Location = new System.Drawing.Point(0, 0);
                        lilTagCloud.Name = "linkLabel1";
                        lilTagCloud.TabStop = true;
                        lilTagCloud.Text = Convert.ToString(tag.Name);
                        lilTagCloud.Click += new EventHandler(lilTagCloud_Click);

                        flowLayoutPanel.Controls.Add(lilTagCloud);
                    }
                    else if (tag.myTag == true)
                    {
                        LinkLabel lilTagCloud = new LinkLabel();
                        lilTagCloud.AutoSize = true;

                        TagSize = Convert.ToSingle(tag.Weight) / 100.0F * maxsize + mintagsize;

                        lilTagCloud.Font = new System.Drawing.Font("Microsoft Sans Serif", TagSize);
                        lilTagCloud.Location = new System.Drawing.Point(0, 0);
                        lilTagCloud.Name = "linkLabel1";
                        lilTagCloud.TabStop = true;
                        lilTagCloud.Text = Convert.ToString(tag.Name);
                        lilTagCloud.Click += new EventHandler(lilTagCloud_Click);

                        flowLayoutPanel.Controls.Add(lilTagCloud);
                    }
                }
            }
            this.ResumeLayout(false);
        }

        public void Updater()
        {
            SortTags();
            RenderCloud();
        }

        void lilTagCloud_Click(object sender, EventArgs e)
        {
            LinkLabel l = (LinkLabel)sender;

            selectedTag = l.Text;

            // Fire the TagSelected event
            TagCloudEventArgs args = new TagCloudEventArgs(TagCloudEventArgs.TagCloudEventType.TagSelected);
            if (TagSelected != null)
                TagSelected(this, args);
            
        }

        private void lnkWhatsThis_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            MessageBox.Show("This is a tag cloud\n A list of keywords where size reflects popularity.", "What is a Tag Cloud?", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }

        private void chkAlphabetical_CheckedChanged(object sender, EventArgs e)
        {
            // Update the sort order option
            if (chkAlphabetical.Checked)
                sortBy = SortOrder.Alphabetical;
            else
                sortBy = SortOrder.Size;

            // We do not need to do this in chkBysize as well, because CheckChanged is called
            // both when check is set and when it is removed
            SortTags();
            RenderCloud();
        }

        private void chkOnlyMine_CheckedChanged(object sender, EventArgs e)
        {
            showMyTagsOnly = chkOnlyMine.Checked;
            SortTags();
            RenderCloud();
        }
    }

    public class TagCloudEventArgs : EventArgs
    {
        public enum TagCloudEventType
        {
            TagSelected
        }

        private TagCloudEventType eventType;

        public TagCloudEventType EventType
        {
            get { return eventType; }
            set { eventType = value; }
        }

        public TagCloudEventArgs(TagCloudEventType et)
        {
            eventType = et;
        }
    }

    public delegate void TagCloudEventHandler(
      object sender, TagCloudEventArgs e);
}

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