53 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C#
		
	
	
	
	
	
			
		
		
	
	
			53 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C#
		
	
	
	
	
	
| using System;
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| using System.Collections.Generic;
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| using System.Linq;
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| using System.Text;
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| using System.Threading.Tasks;
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| using System.Windows.Forms;
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| 
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| namespace Volian.Controls.Library
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| {
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|     //Class to handle bug in Windows WinForms ListBox
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|     // that autoselects first item when no items are selected 
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|     public partial class ListBoxMulti : ListBox
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|     {
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|         public ListBoxMulti()
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|         {
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|             Visible = true;
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|             SelectionMode = SelectionMode.MultiSimple;
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| 
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|             SelectedIndexChanged += lb_SelectedIndexChanged;
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| 
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|             Disposed += ListBoxMulti_Disposed;
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|         }
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| 
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|         //singleselectedindex
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|         // will help to fix bug in Winforms ListBox
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|         // that autoselects first item when no items are selected
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|         // -1 = multi or set to this after 1st initialization
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|         // if this = 0 and only 1 item selected,
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|         // that means item was autoselected, so clear all items.
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|         public int singleselectedindex { get; set; }
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|         private void lb_SelectedIndexChanged(object sender, EventArgs e)
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|         {
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|             ListBoxMulti tmp = (ListBoxMulti)sender;
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| 
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|             if (tmp.SelectedItems.Count == 1 && tmp.singleselectedindex == 0)
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|             {
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|                 tmp.ClearSelected();
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|             }
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|             else if (tmp.SelectedItems.Count == 1)
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|                 tmp.singleselectedindex = tmp.SelectedIndex;
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|             else
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|                 tmp.singleselectedindex = -1;
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| 
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|         }
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| 
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|         //remove event when get rid of object
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|         private void ListBoxMulti_Disposed(object sender, EventArgs e)
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|         {
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|             SelectedIndexChanged -= lb_SelectedIndexChanged;
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|         }
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|     }
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| }
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