Comments on Matt Lacey's Blog: The popularity of TombstoneHelper

if listbox in ScrollViewer (ScrollViewer.VerticalS...

2011-12-23T02:44:24.229Z

if listbox in ScrollViewer (ScrollViewer.VerticalScrollBarVisibility="Disabled"), when user scrolls it very fast, it is very very smooth,no element of it can not appear, but it "drinks" memory like beer :D

@Vodka In that case you may as well just use an It...

2011-12-22T14:56:53.765Z

@Vodka
In that case you may as well just use an ItemsControl rather than a Listbox as all you're essentially doing is replacing the Listbox's internal scrollviewer with one outside it.
How is this "better than a normal Listbox"?
If this is a large list of items (more than a 3 screens full) then this will be hurting your performance as all the items will have to be rendered and scrolled when you manipulate the list. The listbox adds virtualisation of items to avoid this.

"Grid" "Grid.Ro...

2011-12-22T14:44:04.229Z

"Grid"
"Grid.RowDefinitions"
"RowDefinition Height="*" /"
"/Grid.RowDefinitions"
"ScrollViewer"
"StackPanel"
"ListBox ScrollViewer.VerticalScrollBarVisibility="Disabled"""/ListBox"
"/StackPanel"
"/ScrollViewer"
"/Grid"

Hi Matt Lacey i use this code ...

2011-12-22T14:40:29.770Z

Hi Matt Lacey
i use this code

it is better than use normal listbox...
But i have a another big issue, i add ContextMenu, with items are near ApplicationBar, ContextMenu is obscured...

@Vodka Having items of a consistent size (i.e. not...

2011-12-22T12:15:10.314Z

@Vodka
Having items of a consistent size (i.e. not a dynamic height) and having a simple itemtemplate would be my first tips for trying to create a smooth experience.

Thanks for your helpful advice. I bother you again...

2011-12-21T14:14:46.783Z

Thanks for your helpful advice. I bother you again :D, do you have some tips for smooth scrolling Listbox. I read a lot of guides for this issue. LazyListbox,Deferred Load Listbox but they is not good for me :(, my listbox do not have big images, but scrollvier is not smooth...

@Vodka There are lots of reasons for a database lo...

2011-12-20T09:58:38.403Z

@Vodka
There are lots of reasons for a database lookup to perform slowly. Things that could affect it include: size of database; size of rows; number of records being returned; indexes; types of data; complexity of query; ... the list goes on.

Can you provide an example? And maybe post it at http://stackoverflow.com/

There should be no need for it to take that long to read the rows, depending on what you're doing. You may get some tips from http://mobileworld.appamundi.com/blogs/andywigley/archive/2011/12/14/windows-phone-linq-to-sql-and-data-virtualization.aspx

@Matt Lacey How do you speed up to select data fro...

2011-12-20T02:28:19.328Z

@Matt Lacey
How do you speed up to select data from database (SQL CE), I take two seconds to get 50 records. You have some tips ? This is my first time I write a programming with WP, it is difficult to start.

@Vodka Yes, Converters can also affect performance...

2011-12-19T20:29:10.729Z

@Vodka
Yes, Converters can also affect performance.
In the past I've improved things by adding extra properties to the ViewModel which have the conversions applied. This seems to be faster.

Oh, I used a lot of IValueConverter, its make List...

2011-12-19T03:38:25.366Z

Oh, I used a lot of IValueConverter, its make Listbox slower?

@Matt Lacey, Thanks you to reply. I try to make D...

2011-12-19T03:36:44.430Z

@Matt Lacey,
Thanks you to reply. I try to make DataTemplate smaller and load number of items less than. Thanks you agian :D

@vodka There are 2 things which can affect Listb...

2011-12-18T21:53:44.329Z

@vodka

There are 2 things which can affect Listbox load performance: the complexity of the datatemplate; and the number of items you're adding.

Reducing the complexity of the template may be possible depending on your requirements.

If you can't get away with actually having a smaller number of items in your list, you should look to virtualise the list so that it's only necessary to render the template for a smaller number of items.

I have a listbox (in windows phone 7) with a lot o...

2011-12-18T10:44:37.384Z

I have a listbox (in windows phone 7) with a lot of controls inside(Border, checkbox, image, and textblock) when i bind data to it, it is a very slow to show in pivot control, Can in guide me how to improve perform? Thanks (Sorry for my english very bad)