Re: How to load 100,000 list view items without application freeze? - C# Discussion Boards

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Re: How to load 100,000 list view items without application freeze?

Paw Jershauge1-Feb-11 8:38

Paw Jershauge

1-Feb-11 8:38

Ohh and by the way its your background collection that has to change, and when it does, just reset the Virtual item count on the listview, then it will reload, all visible items (from index, to index) from the background collection. Wink | ;)

With great code, comes great complexity, so keep it simple stupid... $Shucks | :-\$ $Shucks | :-\$

Re: How to load 100,000 list view items without application freeze?

Not Active31-Jan-11 12:18

Not Active

31-Jan-11 12:18

No you missed the point. No one was telling you they couldn't handle it, or that the controls could not support it. They have been telling you it is not a good design. And using the argument that Microsoft does it is not valid. The Event Viewer and such controls are written specifically for high performance situation in C++. You are not doing that are you?

I know the language. I've read a book. - _Madmatt

Re: How to load 100,000 list view items without application freeze?

Member 16746131-Jan-11 23:47

Member 167461

31-Jan-11 23:47

this entire thread got way too much attention...

do or do not, there is no try

Re: How to load 100,000 list view items without application freeze?

Chesnokov Yuriy1-Feb-11 1:12

Chesnokov Yuriy

1-Feb-11 1:12

because the topic is a challenge to display 100,000 in as little time as possible, and to find a user who may process them all Smile | :)

Чесноков

Re: How to load 100,000 list view items without application freeze?

Umbaraumba31-Jan-11 23:52

Umbaraumba

31-Jan-11 23:52

The common way is to load items which are currently visible (plus some more for a buffer) and continue loading items on demand as user scrolls the list down.

Re: How to load 100,000 list view items without application freeze?

vsysolts31-Jan-11 23:54

vsysolts

31-Jan-11 23:54

Preload entries for viewable area and maybe a little around, then load entries only when they should be shown. Cannot specify more concrete, haven't programmed for windows for years. NEVER ever do progress bars for filling controls, this nerves a lot especially if you clicked the wrong control, always use lazy loading. Java AWT is particularly good designed for this approach Smile | :)

Re: How to load 100,000 list view items without application freeze?

reshi9991-Feb-11 0:32

reshi999

1-Feb-11 0:32

I use the telerik winforms suite for similar operations, because it can Laugh | :laugh:

Telerik gridview

Re: How to load 100,000 list view items without application freeze?

franva1-Feb-11 0:55

franva

1-Feb-11 0:55

I met the similar problem.

Once I wrote a program for retrieving images from a website and I want that users can be notified about the downloading process, so I added a status bar on main GUI, and let the downloading process works on the other thread(let's say B), when it is retrieving the images , the B has to report its status to GUI which is on main thread(let's say A).

But B can not access the status bar which belongs to A. So there is a method call BeginInvoke(xxxx);
With this method, it enables B to access resourses on A.

So I think it should be the answer that you are looking for.

Give me reply whatever it works or not Smile | :)

cheers

Re: How to load 100,000 list view items without application freeze?

Chesnokov Yuriy1-Feb-11 1:03

Chesnokov Yuriy

1-Feb-11 1:03

You need to use background worker and report the progress with its ReportProgress() function.

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Re: How to load 100,000 list view items without application freeze?

Matthew Barnett1-Feb-11 1:17

Matthew Barnett

1-Feb-11 1:17

Is the code calling BeginUpdate and EndUpdate? It might make a difference, but it's still going to be slow...

Re: How to load 100,000 list view items without application freeze?

Chesnokov Yuriy1-Feb-11 1:24

Chesnokov Yuriy

1-Feb-11 1:24

No, I set the list view Visible to false during events addition.
Otherwise the process is very slow.

Чесноков

Re: How to load 100,000 list view items without application freeze?

loyal ginger1-Feb-11 2:36

loyal ginger

1-Feb-11 2:36

Thanks for this question. I have an application with the same problem. The answers by some smart folks here are very helpful in solving this problem.

Re: How to load 100,000 list view items without application freeze?

237412-Feb-11 7:25

23741

2-Feb-11 7:25

You want a virtual listview ..

How to save image in folder using c# in windows application

Member 368638531-Jan-11 2:37

Member 3686385

31-Jan-11 2:37

How to save image in folder using c# in windows application
Plz Reply to me

Re: How to save image in folder using c# in windows application

Praveen Raghuvanshi31-Jan-11 2:42

Praveen Raghuvanshi

31-Jan-11 2:42

I googled "save image in C#" and found the below link as the first one that should suffice your requirement.

http://msdn.microsoft.com/en-us/library/9t4syfhh.aspx[^]

You can use Image.Save on any event in the windows application.

If you are looking for something specific, please elaborate.

Praveen Raghuvanshi
Software Developer

Please Reply to me...

Member 368638531-Jan-11 2:30

Member 3686385

31-Jan-11 2:30

I want to show an image on crystal report. the image is saved in database (sql) and the datatype of field is image.
i saved the image by converting it (image) in binary form.

Is there some way to show that image on crystal report . its an windows application.

plz help me

Re: Please Reply to me...

Praveen Raghuvanshi31-Jan-11 2:46

Praveen Raghuvanshi

31-Jan-11 2:46

Here is the link http://www.shabdar.org/store-save-images-in-sql-server.html[^]

Check if this helps!!!

Praveen Raghuvanshi
Software Developer

Re: Please Reply to me...

Not Active31-Jan-11 2:51

Not Active

31-Jan-11 2:51

Please have a look at How to get an answer to your question[^]

A subject of "Please Reply to me..." is not very descriptive and will not get you many replies.

I know the language. I've read a book. - _Madmatt

Keyboard Language and Settings

Anubhava Dimri31-Jan-11 1:49

Anubhava Dimri

31-Jan-11 1:49

Hello Experts,

Actually i have generate a problem while Keypress on Processing Global Keyboard Hook.
My Current Keyboard Language is Russian. When i press any Key. It Works Successfully But it displays US Keyboard data On Global Appliation.

Link is given Below.

Processing Global Mouse and Keyboard Hooks in C#

Processing Global Mouse and Keyboard Hooks in C#[^]

Thanks & Regards

If you can think then I Can.

Re: Keyboard Language and Settings

Eddy Vluggen31-Jan-11 7:21

Eddy Vluggen

31-Jan-11 7:21

eg_Anubhava wrote:
My Current Keyboard Language is Russian. When i press any Key. It Works Successfully But it displays US Keyboard data On Global Appliation.

Keyboard-hooks return virtual key-codes[^], not characters in a specific encoding. The hook itself doesn't even report the difference between a capital A and a lower-a, it only reports that the "A"-key had been pressed (with or without the Shift-key/Capslock)

I are Troll Suspicious | :suss:

Re: Keyboard Language and Settings

Anubhava Dimri31-Jan-11 18:40

Anubhava Dimri

31-Jan-11 18:40

Hello Eddy,
Thanks for reply

Actully i want if my keyboard language is Abrahic then my Hook shows Abrahic Characters.
If Selected Language is US then Characters will be display of US.

Pls suggest how can i do this.

Thanks Again

If you can think then I Can.

Re: Keyboard Language and Settings [modified]

Eddy Vluggen31-Jan-11 20:37

Eddy Vluggen

31-Jan-11 20:37

eg_Anubhava wrote:

Pls suggest how can i do this.

You can't.

--edit
You still can't after a one-vote, since it's a technical limitation. The keyboard sends a code that represents a key being pressed, not a character in a specific encoding.

Enjoy Big Grin | :-D