Re: [flexcoders] custom itemrender flicker
You might be better off suppressing the setItemAt if it is the same.
That is exactly what I did and it works great. Now the only issue I need to
solve is how the entire collection reloads if only one item is changed. Do
you have any advice on where I should begin looking for that? I am very
comfortable extending and overriding anything.
Thanks alot!
On Mon, Oct 5, 2009 at 10:36 PM, Alex Harui aha...@adobe.com wrote:
It depends on how you coded the renderer. Our list classes have very
general and somewhat inefficient update strategies because we want to make
sure most collection updates renderer correctly. I haven’t looked at how
Spark List thinks, but mx:List will refresh all renderers even if only one
item changes because it doesn’t know if another renderer might have
“look-ahead” and also care about the item even though its data item is some
other item in the collection.
You might be better off suppressing the setItemAt if it is the same.
Alex Harui
Flex SDK Developer
Adobe Systems Inc. http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
*From:* flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] *On
Behalf Of *Baz
*Sent:* Monday, October 05, 2009 3:18 PM
*To:* flexcoders@yahoogroups.com
*Subject:* Re: [flexcoders] custom itemrender flicker
Hey Alex, thanks a lot for your reply. So it is *proper* behaviour that if
you setItemAt in a custom itemrenderer that the whole control is rebuilt
visually? Incidentally I am using Flex 4, so this might be of even more
interest.
I have a SkinnableDataContainer with an ArrayCollection dataprovider that
holds custom objects ('reports' in this case).
If my current collection has:
1. Report #1 = Name: 1stReportName, Path: 1stReportPath
2. Report #2 = Name: 2ndReportName, Path: 2ndReportPath
And then I do a myArrayCollection.setItemAt(Report1, 0), which basically
sets the first item to the same report it currently has. The itemrenderer
empties of all items, then re-displays them, causing a flicker or flash that
is noticeable on a slow computer.
Wouldn't it make more sense for the itemrender NOT to re-build itself from
scratch on every change? What if you had 100 items and u onl;y set one item?
Thanks a lot!
Baz
On Mon, Oct 5, 2009 at 3:05 PM, Alex Harui aha...@adobe.com wrote:
It depends on how you wrote the renderer. You can try overriding the
“function set data()” to check for changes to the object referenced by the
renderer, but then if some sub-property changes, the renderer will not
update.
Might be better to understand why it flickers when updating.
Alex Harui
Flex SDK Developer
Adobe Systems Inc. http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
*From:* flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] *On
Behalf Of *Baz
*Sent:* Monday, October 05, 2009 12:32 PM
*To:* flexcoders@yahoogroups.com
*Subject:* [flexcoders] custom itemrender flicker
If I have a custom item render based on an ArrayCollection with 10 times,
and just for fun, I loop through those 10 items and setItemAt the exact same
values that are already there - on screen the list of items reloads in a
sense, re-building itself to the exact same values. I would like that in
such a case, the on-screen controls know that they are the same as before
and not to rebuild themselves. Is this possible? Can I intercept some event
to double check whether they are the same or different?
The goal of course, is to have this behaviour even if one some items
changed. For example if I change only the 10th item, I would expect only the
10th item to refresh, no the whole collection.
Thanks for any ideas!
P.S. I am not useing refresh() on the ArrayCollection is it set to
auto-update. Also, all my setItemAt calls are done in commitProperties()
RE: [flexcoders] custom itemrender flicker
I'm not sure what you mean by entire collection reloads. What
collectionChange events are being dispatched (what is the .kind property on the
event). I don' t see anything drastic in the code for REPLACE, but REFRESH or
RESET might be a problem. However those shouldn't be dispatched on setItemAt
Alex Harui
Flex SDK Developer
Adobe Systems Inc.http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
From: flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] On Behalf
Of Baz
Sent: Tuesday, October 06, 2009 11:26 AM
To: flexcoders@yahoogroups.com
Subject: Re: [flexcoders] custom itemrender flicker
You might be better off suppressing the setItemAt if it is the same.
That is exactly what I did and it works great. Now the only issue I need to
solve is how the entire collection reloads if only one item is changed. Do you
have any advice on where I should begin looking for that? I am very comfortable
extending and overriding anything.
Thanks alot!
On Mon, Oct 5, 2009 at 10:36 PM, Alex Harui
aha...@adobe.commailto:aha...@adobe.com wrote:
It depends on how you coded the renderer. Our list classes have very general
and somewhat inefficient update strategies because we want to make sure most
collection updates renderer correctly. I haven't looked at how Spark List
thinks, but mx:List will refresh all renderers even if only one item changes
because it doesn't know if another renderer might have look-ahead and also
care about the item even though its data item is some other item in the
collection.
You might be better off suppressing the setItemAt if it is the same.
Alex Harui
Flex SDK Developer
Adobe Systems Inc.http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
From: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
[mailto:flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com] On
Behalf Of Baz
Sent: Monday, October 05, 2009 3:18 PM
To: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
Subject: Re: [flexcoders] custom itemrender flicker
Hey Alex, thanks a lot for your reply. So it is *proper* behaviour that if you
setItemAt in a custom itemrenderer that the whole control is rebuilt visually?
Incidentally I am using Flex 4, so this might be of even more interest.
I have a SkinnableDataContainer with an ArrayCollection dataprovider that holds
custom objects ('reports' in this case).
If my current collection has:
1. Report #1 = Name: 1stReportName, Path: 1stReportPath
2. Report #2 = Name: 2ndReportName, Path: 2ndReportPath
And then I do a myArrayCollection.setItemAt(Report1, 0), which basically sets
the first item to the same report it currently has. The itemrenderer empties of
all items, then re-displays them, causing a flicker or flash that is noticeable
on a slow computer.
Wouldn't it make more sense for the itemrender NOT to re-build itself from
scratch on every change? What if you had 100 items and u onl;y set one item?
Thanks a lot!
Baz
On Mon, Oct 5, 2009 at 3:05 PM, Alex Harui
aha...@adobe.commailto:aha...@adobe.com wrote:
It depends on how you wrote the renderer. You can try overriding the function
set data() to check for changes to the object referenced by the renderer, but
then if some sub-property changes, the renderer will not update.
Might be better to understand why it flickers when updating.
Alex Harui
Flex SDK Developer
Adobe Systems Inc.http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
From: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
[mailto:flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com] On
Behalf Of Baz
Sent: Monday, October 05, 2009 12:32 PM
To: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
Subject: [flexcoders] custom itemrender flicker
If I have a custom item render based on an ArrayCollection with 10 times, and
just for fun, I loop through those 10 items and setItemAt the exact same values
that are already there - on screen the list of items reloads in a sense,
re-building itself to the exact same values. I would like that in such a case,
the on-screen controls know that they are the same as before and not to rebuild
themselves. Is this possible? Can I intercept some event to double check
whether they are the same or different?
The goal of course, is to have this behaviour even if one some items changed.
For example if I change only the 10th item, I would expect only the 10th item
to refresh, no the whole collection.
Thanks for any ideas!
P.S. I am not useing refresh() on the ArrayCollection is it set to auto-update.
Also, all my setItemAt calls are done in commitProperties()
[flexcoders] custom itemrender flicker
If I have a custom item render based on an ArrayCollection with 10 times, and just for fun, I loop through those 10 items and setItemAt the exact same values that are already there - on screen the list of items reloads in a sense, re-building itself to the exact same values. I would like that in such a case, the on-screen controls know that they are the same as before and not to rebuild themselves. Is this possible? Can I intercept some event to double check whether they are the same or different? The goal of course, is to have this behaviour even if one some items changed. For example if I change only the 10th item, I would expect only the 10th item to refresh, no the whole collection. Thanks for any ideas! P.S. I am not useing refresh() on the ArrayCollection is it set to auto-update. Also, all my setItemAt calls are done in commitProperties()
RE: [flexcoders] custom itemrender flicker
It depends on how you wrote the renderer. You can try overriding the function set data() to check for changes to the object referenced by the renderer, but then if some sub-property changes, the renderer will not update. Might be better to understand why it flickers when updating. Alex Harui Flex SDK Developer Adobe Systems Inc.http://www.adobe.com/ Blog: http://blogs.adobe.com/aharui From: flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] On Behalf Of Baz Sent: Monday, October 05, 2009 12:32 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] custom itemrender flicker If I have a custom item render based on an ArrayCollection with 10 times, and just for fun, I loop through those 10 items and setItemAt the exact same values that are already there - on screen the list of items reloads in a sense, re-building itself to the exact same values. I would like that in such a case, the on-screen controls know that they are the same as before and not to rebuild themselves. Is this possible? Can I intercept some event to double check whether they are the same or different? The goal of course, is to have this behaviour even if one some items changed. For example if I change only the 10th item, I would expect only the 10th item to refresh, no the whole collection. Thanks for any ideas! P.S. I am not useing refresh() on the ArrayCollection is it set to auto-update. Also, all my setItemAt calls are done in commitProperties()
Re: [flexcoders] custom itemrender flicker
Hey Alex, thanks a lot for your reply. So it is *proper* behaviour that if
you setItemAt in a custom itemrenderer that the whole control is rebuilt
visually? Incidentally I am using Flex 4, so this might be of even more
interest.
I have a SkinnableDataContainer with an ArrayCollection dataprovider that
holds custom objects ('reports' in this case).
If my current collection has:
1. Report #1 = Name: 1stReportName, Path: 1stReportPath
2. Report #2 = Name: 2ndReportName, Path: 2ndReportPath
And then I do a myArrayCollection.setItemAt(Report1, 0), which basically
sets the first item to the same report it currently has. The itemrenderer
empties of all items, then re-displays them, causing a flicker or flash that
is noticeable on a slow computer.
Wouldn't it make more sense for the itemrender NOT to re-build itself from
scratch on every change? What if you had 100 items and u onl;y set one item?
Thanks a lot!
Baz
On Mon, Oct 5, 2009 at 3:05 PM, Alex Harui aha...@adobe.com wrote:
It depends on how you wrote the renderer. You can try overriding the
“function set data()” to check for changes to the object referenced by the
renderer, but then if some sub-property changes, the renderer will not
update.
Might be better to understand why it flickers when updating.
Alex Harui
Flex SDK Developer
Adobe Systems Inc. http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
*From:* flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] *On
Behalf Of *Baz
*Sent:* Monday, October 05, 2009 12:32 PM
*To:* flexcoders@yahoogroups.com
*Subject:* [flexcoders] custom itemrender flicker
If I have a custom item render based on an ArrayCollection with 10 times,
and just for fun, I loop through those 10 items and setItemAt the exact same
values that are already there - on screen the list of items reloads in a
sense, re-building itself to the exact same values. I would like that in
such a case, the on-screen controls know that they are the same as before
and not to rebuild themselves. Is this possible? Can I intercept some event
to double check whether they are the same or different?
The goal of course, is to have this behaviour even if one some items
changed. For example if I change only the 10th item, I would expect only the
10th item to refresh, no the whole collection.
Thanks for any ideas!
P.S. I am not useing refresh() on the ArrayCollection is it set to
auto-update. Also, all my setItemAt calls are done in commitProperties()
RE: [flexcoders] custom itemrender flicker
It depends on how you coded the renderer. Our list classes have very general
and somewhat inefficient update strategies because we want to make sure most
collection updates renderer correctly. I haven't looked at how Spark List
thinks, but mx:List will refresh all renderers even if only one item changes
because it doesn't know if another renderer might have look-ahead and also
care about the item even though its data item is some other item in the
collection.
You might be better off suppressing the setItemAt if it is the same.
Alex Harui
Flex SDK Developer
Adobe Systems Inc.http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
From: flexcoders@yahoogroups.com [mailto:flexcod...@yahoogroups.com] On Behalf
Of Baz
Sent: Monday, October 05, 2009 3:18 PM
To: flexcoders@yahoogroups.com
Subject: Re: [flexcoders] custom itemrender flicker
Hey Alex, thanks a lot for your reply. So it is *proper* behaviour that if you
setItemAt in a custom itemrenderer that the whole control is rebuilt visually?
Incidentally I am using Flex 4, so this might be of even more interest.
I have a SkinnableDataContainer with an ArrayCollection dataprovider that holds
custom objects ('reports' in this case).
If my current collection has:
1. Report #1 = Name: 1stReportName, Path: 1stReportPath
2. Report #2 = Name: 2ndReportName, Path: 2ndReportPath
And then I do a myArrayCollection.setItemAt(Report1, 0), which basically sets
the first item to the same report it currently has. The itemrenderer empties of
all items, then re-displays them, causing a flicker or flash that is noticeable
on a slow computer.
Wouldn't it make more sense for the itemrender NOT to re-build itself from
scratch on every change? What if you had 100 items and u onl;y set one item?
Thanks a lot!
Baz
On Mon, Oct 5, 2009 at 3:05 PM, Alex Harui
aha...@adobe.commailto:aha...@adobe.com wrote:
It depends on how you wrote the renderer. You can try overriding the function
set data() to check for changes to the object referenced by the renderer, but
then if some sub-property changes, the renderer will not update.
Might be better to understand why it flickers when updating.
Alex Harui
Flex SDK Developer
Adobe Systems Inc.http://www.adobe.com/
Blog: http://blogs.adobe.com/aharui
From: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
[mailto:flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com] On
Behalf Of Baz
Sent: Monday, October 05, 2009 12:32 PM
To: flexcoders@yahoogroups.commailto:flexcoders@yahoogroups.com
Subject: [flexcoders] custom itemrender flicker
If I have a custom item render based on an ArrayCollection with 10 times, and
just for fun, I loop through those 10 items and setItemAt the exact same values
that are already there - on screen the list of items reloads in a sense,
re-building itself to the exact same values. I would like that in such a case,
the on-screen controls know that they are the same as before and not to rebuild
themselves. Is this possible? Can I intercept some event to double check
whether they are the same or different?
The goal of course, is to have this behaviour even if one some items changed.
For example if I change only the 10th item, I would expect only the 10th item
to refresh, no the whole collection.
Thanks for any ideas!
P.S. I am not useing refresh() on the ArrayCollection is it set to auto-update.
Also, all my setItemAt calls are done in commitProperties()
