c# - binding windows 8 textBlock in MVVM light -

c# - binding windows 8 textBlock in MVVM light -

i 'm having problem textblock/textbox binding. textblock doesn't display property's content. when 'm debugging app, property has content. how can it? xaml.

<textblock horizontalalignment="left" margin="730,191,0,0" textwrapping="wrap" text="{binding xmlcontentfile, mode=twoway}" verticalalignment="top" height="429" width="465"/>

i finding simple code in web, didn't find code.

code property

public string xmlcontentfile { { homecoming this.xmlcontentfile; } set { this.xmlcontentfile = value; } }

my datacontext

datacontext="{binding main, source={staticresource locator}}">

method load xml file string variable

public async void xmlcontentload() { if (selectfile != null) { seek { storagefolder storagefolder = applicationdata.current.localfolder; storagefile storagefile = await storagefolder.getfileasync(selectfile); xmlfiletextcontent = await fileio.readtextasync(storagefile); } grab (exception) { throw new exception("bug"); } } }

the problem xmlcontentfile property doesn't raise notifications when it's changed. viewmodel needs implement inotifypropertychanged , raise event whenever property has changed.

it's view , info bindings getting setup , executed before xmlcontentload completes (it's asynchronous). if binding has completed before info loaded, way binding happen 1 time again if property raises notification has changed.

it's worth pointing out in xmlcontentload method you're setting private variable , not public property.

xmlfiletextcontent = await fileio.readtextasync(storagefile);

setting private variable never raise property alter notification if have setter code wired raise notification. you'll either need alter xmlcontentload set property , have onpropertychanged notification in setter (recommended) or you'll need phone call onpropertychanged after set private variable (not recommended).

hope helps.

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c# xaml windows-8 mvvm-light