Re: Picturebox and Progressbar question - C# Discussion Boards

11-May-12 4:13

I have a win form that you can click a browse button - navigate to your image file - and view the image in the win form. I've been trying to associate my progress bar to the load time of the image selected with no success. Can anyone take a look at my code and see what I'm missing?

private void startButton_Click(object sender, EventArgs e) //Opens file browsing dialog
       {
               OpenFileDialog open = new OpenFileDialog();
               open.FileName = "";
               open.Filter = "Image Files(*.tif; *.jpg; *.jpeg; *.gif; *.bmp)|*.tif; *.jpg; *.jpeg; *.gif; *.bmp";
               open.InitialDirectory = @"g:\All Scanned Jobs\";
               if (open.ShowDialog() != DialogResult.Cancel)
               {
                   // display image in picture box
                   pictureBox1.Image = new Bitmap(open.FileName);
                   pictureBox1.SizeMode = PictureBoxSizeMode.Zoom;
                   pictureBox1.WaitOnLoad = false;
                   pictureBox1.LoadAsync(open.FileName);
               }
       }
       void pictureBox1_LoadProgressChanged(object sender, ProgressChangedEventArgs e) //Sets pBar value as file opens
       {
           progressBar1.Value = e.ProgressPercentage;
       }

Sentenryu11-May-12 4:32

11-May-12 4:32

make sure the pictureBox1_LoadProgressChanged method is associated with the pictureBox event, i tested your code here and it works without modifications, have you tried to put a breakpoint into the pictureBox1_LoadProgressChanged method?

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Hagen McCarthy11-May-12 4:39

11-May-12 4:39

I have this in my Form1.Designer.cs code.

//
// pictureBox1
//
this.pictureBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
| System.Windows.Forms.AnchorStyles.Left)
| System.Windows.Forms.AnchorStyles.Right)));
this.pictureBox1.BackColor = System.Drawing.SystemColors.ButtonFace;
this.pictureBox1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
this.pictureBox1.ImageLocation = "";
this.pictureBox1.Location = new System.Drawing.Point(13, 71);
this.pictureBox1.Name = "pictureBox1";
this.pictureBox1.Size = new System.Drawing.Size(1303, 701);
this.pictureBox1.TabIndex = 3;
this.pictureBox1.TabStop = false;
this.pictureBox1.LoadProgressChanged +=new System.ComponentModel.ProgressChangedEventHandler(pictureBox1_LoadProgressChanged);

Is that where it needs to be?

Sentenryu11-May-12 5:06

11-May-12 5:06

your code are exactly the same as mine, still, works fine, the image loads pretty fast, so the progressbar moves fast, but stops at 100% you said that a breakpoint don't helped, what was the behavior? the method isn't being called? the image isn't loading?

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Hagen McCarthy11-May-12 5:10

11-May-12 5:10

The break gives me this:

ImageViewer.exe!ImageViewer.Form1.pictureBox1_LoadProgressChanged(object sender, System.ComponentModel.ProgressChangedEventArgs e) Line 71 + 0x5 bytes C#

ImageViewer.exe!ImageViewer.Program.Main() Line 18 + 0x1d bytes C#

I'm using 2010 Express of visual studio would that have anything to do with it?

Hagen McCarthy11-May-12 5:21

11-May-12 5:21

And everything works just fine except I do not see the progress bar fill up at all and once the image is done loading completely I still dont see any green.

Hagen McCarthy11-May-12 4:59

11-May-12 4:59

And a breakpoint didn't come up with much help.

BobJanova11-May-12 6:37

BobJanova

11-May-12 6:37

Did you set the Maximum on the progress bar to be something sensible?

Hagen McCarthy11-May-12 7:37

11-May-12 7:37

I have the Min set to 0 and the Max set to 100.

Alan N11-May-12 7:28

Alan N

11-May-12 7:28

Member 8956301 wrote:
// display image in picture box
pictureBox1.Image = new Bitmap(open.FileName);
pictureBox1.SizeMode = PictureBoxSizeMode.Zoom;
pictureBox1.WaitOnLoad = false;
pictureBox1.LoadAsync(open.FileName);

OK, let's break this code down line by line
1) Open the file, create a bitmap and set as the picturebox image
2) Set size mode
3) tell picturebox that future image loading will be async
4) Do async load from the file, this is now reloading

So you are loading the image twice.

I think all you need is

pictureBox1.WaitOnLoad = false;
pictureBox1.LoadAsync(open.FileName);

Alan.

Hagen McCarthy11-May-12 7:38

11-May-12 7:38

Thanks for catching that for me. I've made that corrections but the progress bar still does nothing.

Dave Kreskowiak12-May-12 4:33

Dave Kreskowiak

12-May-12 4:33

So how long is it taking to load the image?? The ProgressChange event if only fired every once in a while, not on every byte that's loaded. It may not even be fired at 100% either.

There's a second event that you can handle to get notified that the image is completely loaded. That's the LoadCompleted event. When this one is raised, you can set your progress bar to 100% and consider the operation done.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak

Hagen McCarthy14-May-12 2:27

Web Camera Application using C#

14-May-12 2:27

It's taking a good 10 to 12 seconds to open.

austinwales11-May-12 3:14

austinwales

11-May-12 3:14

I need help with an SDK to develop an application that will work with the built in camera or any external camera. The camera should be able to take snapshots.. This application will of course be used on windows and will be programmed with C#..

Ravi Bhavnani11-May-12 3:25

Ravi Bhavnani

11-May-12 3:25

What part of the app do you need help with? Please indicate what you've tried and ask a more specific question if possible. This will allow us to help you better.

/ravi

My new year resolution: 2048 x 1536
Home | Articles | My .NET bits | Freeware
ravib(at)ravib(dot)com

Sentenryu11-May-12 4:41

11-May-12 4:41

i know i shouldn't do this (post here), but actually i'm interested in this kind of thing to, you have any material about how to connect to built-in web cams from c#? or a starting point? i've only found unmanaged solutions, so if you have any managed solution, please share... Smile | :)

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Eddy Vluggen11-May-12 5:46

Eddy Vluggen

11-May-12 5:46

Sentenryu wrote:
or a starting point?

Did you try to search this site? We got a lot of articles on webcam's, and most of them are in managed code.

Bastard Programmer from Hell Suspicious | :suss:

Sentenryu11-May-12 6:53

11-May-12 6:53

tried, only found solutions that use a unmanaged dll, i'll try once more...

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Eddy Vluggen11-May-12 8:02

Eddy Vluggen

11-May-12 8:02

Try this[^] one.

Bastard Programmer from Hell Suspicious | :suss:

Sentenryu11-May-12 8:39

11-May-12 8:39

thanks, i've seen this article, the problem is that i can't use external dlls (stupid requirement that i'm trying to remove...)

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)