Bind List<Object> to a comboxbox in c# wpf -

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i have static class named building contains list<beam> beams property;

public static class building {     public static readonly list<beam> beams = new list<beam>(); }  public class beam {     public string story;     public double elevation; }

i'm trying bind building.beams combobox in xaml elevation , story properties of each item in building.beams list displayed in different columns in combobox. have been able implement 2 columns, can't bind these properties.

here have tried far:

<combobox x:name="cmbbuilding"  itemssource="{binding}">     <combobox.itemtemplate>         <datatemplate>             <grid width="300">                 <textblock width="150"  text="{binding path=story }"/>                 <textblock width="150" text="{binding path=elevation}"/>             </grid>         </datatemplate>     </combobox.itemtemplate> </combobox>  var b1 = new beam { elevation = 320, story = "st1" }; var b2 = new beam { elevation = 640, story = "st2" }; building.beams.add(b1); building.beams.add(b2);

try example:

xaml

<grid>     <combobox x:name="cmbbuilding" width="100" height="25" itemssource="{binding path=beams}">         <combobox.itemtemplate>             <datatemplate>                 <grid width="300">                     <textblock width="150" text="{binding path=story}" horizontalalignment="left" />                     <textblock width="150" text="{binding path=elevation}" horizontalalignment="right" />                 </grid>             </datatemplate>         </combobox.itemtemplate>     </combobox>      <button content="add item" verticalalignment="top" click="button_click" /> </grid>

code-behind

public partial class mainwindow : window {     building building = new building();      public mainwindow()     {         initializecomponent();          building.beams = new list<beam>();          building.beams.add(new beam                             {                                 elevation = 320,                                 story = "st1"                             });          this.datacontext = building;     }      private void button_click(object sender, routedeventargs e)     {         var b1 = new beam { elevation = 320, story = "st1" };         var b2 = new beam { elevation = 640, story = "st2" };          building.beams.add(b1);         building.beams.add(b2);          cmbbuilding.items.refresh();     } }  public class building {     public list<beam> beams     {         get;         set;     } }  public class beam {     public string story      {         get;         set;     }      public double elevation     {         get;         set;     } }

some notes

  • when use properties in binding, need properties , set, not fields.

  • properties, added list<t> automatically update, should call mycombobox.items.refresh() method, or use observablecollection<t>:

observablecollection represents dynamic data collection provides notifications when items added, removed, or when whole list refreshed.


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