Windows phone7-MVVM event binding

Next, go to the previous demo. Next, set a refresh button to update the friend list. Here, you need to bind a command to the button. Of course, this command is a mainviewmodel attribute that implements the icommand interface;

1. Add the refreshcommand class to viewmodel.

Using system; using system. net; using system. windows; using system. windows. controls; using system. windows. documents; using system. windows. ink; using system. windows. input; using system. windows. media; using system. windows. media. animation; using system. windows. shapes; namespace hellowp7.viewmodel {public class refreshcommand: icommand {private readonly mainviewmodel _ viewmodel; Public refreshcommand (mainviewmodel viewmodel) {_ viewmodel = viewmodel;} public bool canexecute (object parameter) {return true;} public event eventhandler canexecutechanged; Public void execute (object parameter) {_ viewmodel. refresh ();}}}
 

2. Add the refresh command attribute in modelviewmodel.

Public icommand refreshcommand {Get; private set ;}
 

 

3. Add refresh data processing in modelviewmodel

 
Public void refresh () {observablecollection <friend> friends = new observablecollection <friend> (friendservice. getfriendsset (); this. Friends = friends; // update the friend list}
 

4. Add the refresh button on the page and add event binding

<Button canvas. Left = "24" canvas. Top = "556" command = "{binding refreshcommand}" content = "refersh" Height = "72"
 

 
Name = "btnrefresh" width = "160"/>
 

 

After running, click Refresh. The data list is updated.

 

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