c# - WPF - MVVM : How to Check/Uncheck all Items in a ListView -

i have following requirements:

1. window show listview multiple items.
2. user should able check (checkbox) item. a) if 1 item, items should unchecked , disabled. b) if checked item unchecked, items should enabled.

as of now, have following incomplete code.

mainwindow xaml:

<window x:class="wpfapplication4.mainwindow"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         title="mainwindow" height="520.149" width="732.463">     <window.resources>         <resourcedictionary source="mainwindowresource.xaml" />     </window.resources>      <grid>      <listview x:name="mylistbox" itemtemplate="{staticresource offeringtemplate}">             <listview.itemspanel>                 <itemspaneltemplate>                     <uniformgrid columns="3" verticalalignment="top"/>                 </itemspaneltemplate>             </listview.itemspanel>         </listview>     </grid> </window> 

datatemplete listview:

<datatemplate x:key="offeringtemplate">     <stackpanel>         <grid isenabled="{binding isenabled}">             <grid.columndefinitions>                 <columndefinition width="8"></columndefinition>                 <columndefinition width="120"></columndefinition>             </grid.columndefinitions>             <grid.rowdefinitions>                 <rowdefinition height="40"></rowdefinition>                 <rowdefinition height="50"></rowdefinition>                 <rowdefinition height="30"></rowdefinition>             </grid.rowdefinitions>             <rectangle grid.column="0" grid.rowspan="3" fill="#f4ca16" />             <label                 grid.column="1"                 grid.row="0"                 content="{binding title}"                 fontsize="18" fontweight="bold"                 margin="0,0,0,0" />             <textblock                 grid.column="1"                 grid.row="1"                 fontsize="10"                 text="{binding description}"                 foreground="black"                 textwrapping="wrapwithoverflow"                 margin="5,0,0,0" />             <checkbox                 grid.column="1"                 grid.row="2"                 fontsize="14"                 ischecked="{binding isselected}"                 verticalalignment="bottom"                 margin="5,0,0,0">                  <textblock text="select" margin="0,-2,0,0"/>             </checkbox>         </grid>     </stackpanel> </datatemplate> 

model:

class mymodel {     public string title { get; set; }     public string description { get; set; }     public bool isselected { get; set; }     public bool isenabled { get; set; } } 

viewmodel:

class myviewmodel : inotifypropertychanged {     private mymodel offering;      public myviewmodel()     {         offering = new mymodel();     }      public int id { get; set; }     public string title     {         { return offering.title; }         set         {             offering.title = value;             raisepropertychanged("title");         }     }     public string description     {         { return offering.description; }         set         {             offering.description = value;             raisepropertychanged("description");         }     }     public bool isselected     {         { return offering.isselected; }         set         {             offering.isselected = value;             raisepropertychanged("isselected");         }     }     public bool isenabled     {         { return offering.isenabled; }         set         {             offering.isenabled = value;             raisepropertychanged("isenabled");         }     }      public event propertychangedeventhandler propertychanged;      private void raisepropertychanged(string propertyname)     {         var handler = propertychanged;         if (handler != null)         {             handler(this, new propertychangedeventargs(propertyname));         }     } } 

this interesting question. since action want applies items in list, logic should in list class level. myviewmodel class fine. need add logic in list class , xaml prism, quite easy.

the list class (not shown in post) contains:

    public observablecollection<myviewmodel> myitems { get; set; } //binding itemssource      private icommand _selectcommand;      public icommand selectcommand     {         { return _selectcommand ?? (_selectcommand = new delegatecommand<myviewmodel>(doselect)); }     }      private void doselect(myviewmodel myviewmodel)     {         foreach(var item in myitems)             if (item != myviewmodel)             {                 item.isselected = false;                 item.isenabled = false;             }     }      private icommand _unselectcommand;      public icommand unselectcommand     {         { return _unselectcommand ?? (_unselectcommand = new delegatecommand<myviewmodel>(dounselect)); }     }      private void dounselect(myviewmodel myviewmodel)     {         foreach (var item in myitems)             if (item != myviewmodel)             {                 item.isenabled = true;             }     } 

there 2 commands, 1 selecting , other unselecting. magic on xaml:

      <listview itemssource="{binding path=myitems}" x:name="listview">             <listview.itemtemplate>                 <datatemplate>                     <checkbox ischecked="{binding path=isselected}" isenabled="{binding path=isenabled}">                         <i:interaction.triggers>                             <i:eventtrigger eventname="checked">                                 <i:invokecommandaction command="{binding elementname=listview, path=datacontext.selectcommand}"                                                        commandparameter="{binding}"/>                             </i:eventtrigger>                             <i:eventtrigger eventname="unchecked">                                 <i:invokecommandaction command="{binding elementname=listview, path=datacontext.unselectcommand}"                                                        commandparameter="{binding}"/>                             </i:eventtrigger>                         </i:interaction.triggers>                     </checkbox>                 </datatemplate>             </listview.itemtemplate>         </listview> 

using prism's triggers, can map checkbox's checked , unchecked event list view model's commands , passing item view model parameter.

it working 1 thing annoying, setting item's isselected separate. when check checkbox, item behind set true through databinding others set through parent view model. if post requirement, can remove ischecked binding , put logic of setting 1 isselected inside list view model, looks clenaer , easier write test code.