xaml - Scrollviewer ChangeView function not scrolling to bottom -
i have used listview inside scrollviewer in windows phone 8.1 rt app. have requirement of scrolling bottom of list change view function not working per requirement.
created sample same scenario:
mainpage.xaml
<page x:class="infilist.mainpage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:infilist" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:customlv="using:infilist" mc:ignorable="d" background="{themeresource applicationpagebackgroundthemebrush}"> <page.resources> <style x:key="listviewstyle1" targettype="listview"> <setter property="istabstop" value="false"/> <setter property="tabnavigation" value="once"/> <setter property="isswipeenabled" value="true"/> <setter property="horizontalcontentalignment" value="stretch"/> <setter property="verticalcontentalignment" value="top"/> <setter property="itemcontainertransitions"> <setter.value> <transitioncollection> <adddeletethemetransition/> <reorderthemetransition/> </transitioncollection> </setter.value> </setter> <setter property="itemspanel"> <setter.value> <itemspaneltemplate> <itemsstackpanel orientation="vertical"/> </itemspaneltemplate> </setter.value> </setter> <setter property="template"> <setter.value> <controltemplate targettype="listview"> <border borderbrush="{templatebinding borderbrush}" borderthickness="{templatebinding borderthickness}" background="{templatebinding background}"> <itemspresenter footertransitions="{templatebinding footertransitions}" footertemplate="{templatebinding footertemplate}" footer="{templatebinding footer}" headertemplate="{templatebinding headertemplate}" header="{templatebinding header}" headertransitions="{templatebinding headertransitions}" horizontalalignment="{templatebinding horizontalcontentalignment}" padding="{templatebinding padding}" verticalalignment="{templatebinding verticalcontentalignment}"/> </border> </controltemplate> </setter.value> </setter> </style> </page.resources> <grid x:name="root"> <scrollviewer x:name="myscrollviewer" viewchanged="onviewchanged" isverticalscrollchainingenabled="true"> <listview x:name="listview" itemssource="{binding collection}" style="{staticresource listviewstyle1}" > <listview.itemcontainerstyle> <style targettype="listviewitem"> <setter property="horizontalcontentalignment" value="stretch"/> <setter property="verticalcontentalignment" value="stretch"/> </style> </listview.itemcontainerstyle> <listview.itemspanel> <itemspaneltemplate> <itemsstackpanel itemsupdatingscrollmode="keepitemsinview"/> </itemspaneltemplate> </listview.itemspanel> <listview.itemtemplate> <datatemplate> <grid background="lightgray" horizontalalignment="left" margin="25"> <textblock margin="25 25 25 50" fontsize="32" text="{binding}" textwrapping="wrapwholewords" maxwidth="200"/> </grid> </datatemplate> </listview.itemtemplate> </listview> </scrollviewer> </grid> <page.bottomappbar> <commandbar> <appbarbutton click="appbarbutton_click"> </appbarbutton> </commandbar> </page.bottomappbar> mainpage.xaml.cs
using system; using system.collections.generic; using system.collections.objectmodel; using system.diagnostics; using system.io; using system.linq; using system.runtime.interopservices.windowsruntime; using windows.foundation; using windows.foundation.collections; using windows.ui.xaml; using windows.ui.xaml.controls; using windows.ui.xaml.controls.primitives; using windows.ui.xaml.data; using windows.ui.xaml.input; using windows.ui.xaml.media; using windows.ui.xaml.navigation; // blank page item template documented @ http://go.microsoft.com/fwlink/?linkid=391641 namespace infilist { /// <summary> /// empty page can used on own or navigated within frame. /// </summary> public sealed partial class mainpage : page { public observablecollection<string> collection { get; set; } private bool incall; private int offset; int _noofelements; public mainpage() { this.initializecomponent(); collection = new observablecollection<string>(); listview.datacontext = this; this.navigationcachemode = navigationcachemode.required; addnumber(0); listview.loaded += listview_loaded; } void listview_loaded(object sender, routedeventargs e) { myscrollviewer.changeview(null, int.maxvalue, null, true); } private void onviewchanged(object sender, scrollviewerviewchangedeventargs e) { scrollviewer view = (scrollviewer)sender; debug.writeline("vertica pffset: " + view.verticaloffset); if ((view.verticaloffset < 0.1 * view.scrollableheight) & !incall) { incall = true; addnumber(++offset); } } private void addnumber(int offset) { int scrollcount = 30; int start = offset * scrollcount; (int = start; < start + scrollcount; i++) { string s= (_noofelements++).tostring() ; if (i % 2 == 0) s += "msdkd kmsdksdk kdsmkd skmcds ckdsmckds ckdsmcksd kcmdskcdsc kdmmcsckdsc" + environment.newline + "sdjndsjnds" + "msdkd kmsdksdk kdsmkd skmcds ckdsmckds ckdsmcksd kcmdskcdsc kdmmcsckdsc" + environment.newline + "sdjndsjnds" + "dssdsddsds"; collection.insert(0,s); } incall = false; } /// <summary> /// scrolls bottom /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void appbarbutton_click(object sender, routedeventargs e) { myscrollviewer.changeview(null, int.maxvalue, null, true); //myscrollviewer.scrolltoverticaloffset(int.maxvalue); //for scrolling till top //myscrollviewer.scrolltoverticaloffset(0); } } } is there way achieve desired functionality?
use scrollviewer's extentheight
scrollviewer.changeview(null, scrollviewer.extentheight, null);
sample: https://github.com/himanshpal/listviewvirtualizationtest
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