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How do I update several controls on my Form1 using BackgroundWorker?

I found several examples that shows how to update UI control using BackgroundWorker.
For example the following code:
BackgroundWorker backgroundWorker1 = new BackgroundWorker();
backgroundWorker1.WorkerReportsProgress = true;
//start the operation on another thread
private void btnStart_Click(object sender, EventArgs e)
{
backgroundWorker1.RunWorkerAsync();
}
//DoWork event handler is executed on a separate thread
private void backgroundWorker1_DoWork(object sender, DoWorkeventArgs e)
{
//a long running operation
for (int i = 1; i < 11; i++)
{
Thread.Sleep(2000);
backgroundWorker1.ReportProgress(i * 10);
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.value = e.ProgressPercentage;
}
That I found here:
https://www.c-sharpcorner.com/UploadFile/Ashush/using-the-backgroundworker-component
The problem is that ALL the examples that I found, shows how to update Only One control on the form. For example the code that I gave, demonstrate how to update a progressBar value.
But this is not a realistic situation, in the real world, I would usually want to update SEVERAL controls on my form.
For example:
progressBar1.Value = 54;
listBox1.SelectedIndex = 2;
button1.BackgroundColor = Color.Yellow;
image1.left = image1.left + 20;
How do I change the code that I showed, in order to update the controls that I gave in the previous lines? There must be an easy way to do that. By the way, my application uses several threads, and each one of them have to update several controls on the UI while they are still running...
I Hope that my question is clear,
Thanks.
Edit:
Neil suggested me to find the solution in this thread:
How do I update the GUI from another thread?
But I saw that people there recommended using BackgroundWorker... which is exactly what I'm asking about.
They didn't explain how to use this method in order to update several UI controls in parallel.

Try something like this:
button1.Invoke(
new Action(
() =>
button1.BackgroundColor = Color.Yellow;
)
);
image1.Invoke(
new Action(
() =>
image1.left = image1.left + 20;
)
);
//etc.

Making a progress bar update in real time in wpf

I'm having some trouble making the progress bar show the updates in real time.
This is my code right now
for (int i = 0; i < 100; i++)
{
progressbar1.Value = i;
Thread.Sleep(100);
}
But for some reason the progress bar shows empty when the function runs, and then nothing until the function finishes running. Can someone explain to me how this can be done? I'm new to C#/WPF so I'm not 100% sure on how I would implement a Dispatcher on a different thread (as seen on some other posts) to fix this problem.
To clarify, my program has a button which when press, grabs the value from a textbox, and uses an API to retrieve info, and create labels based on it. I want the progress bar to update after every row of data is finished processing.
This is what I have right now:
private async void search(object sender, RoutedEventArgs e)
{
var progress = new Progress<int>(value => progressbar1.Value = value);
await Task.Run(() =>
{
this.Dispatcher.Invoke((Action)(() =>
{
some pre-processing before the actual for loop occur
for (int i = 0; i < numberofRows; i++)
{
label creation + adding
((IProgress<int>)progress).Report(i);
}
}));
});
}
Thank you!

If you are using .NET 4.5 or later, you can use async/await:
var progress = new Progress<int>(value => progressBar.Value = value);
await Task.Run(() =>
{
for (int i = 0; i < 100; i++)
{
((IProgress<int>)progress).Report(i);
Thread.Sleep(100);
}
});
You need to mark your method with async keyword to be able to use await, for example:
private async void Button_Click(object sender, RoutedEventArgs e)

Managed to make it work. All I needed to do is instead of making it just
progressBar1.value = i;
I just had to do
progressbar1.Dispatcher.Invoke(() => progressbar1.Value = i, DispatcherPriority.Background);

You should use BackgroundWorker included in .NET, which provides you with methods for reporting the progress of a background thread in an event. The thread which created the BackGroundWorker automatically calls this event.
The BackgroundWorker.ProgressChanged can be used to report the progress of an asynchronous operation to the user.
// This event handler updates the progress bar.
private void backgroundWorker1_ProgressChanged(object sender,
ProgressChangedEventArgs e)
{
this.progressBar1.Value = e.ProgressPercentage;
}
Refer to MSDN for more information about using this.

How to load a windows form in new thread?

c# .net Winforms,IDE: VS 2010
I having two windows from F1, F2.
F1 is the caller, and F2 is the form which I want to load in thread because it is having lots of rich controls on it.
I am able to load the f2 in child thread but it just get visible and goes, because its on child thread.(See Case 1 Code)
Case 1 Code
private void button1_Click(object sender, EventArgs e)
{
StartProgress();
Thread th = new Thread(new ThreadStart(LoadForm));
th.Start();
}
private void StartProgress()
{
progressBar1.Maximum = 100;
progressBar1.Step = 1;
for (int i = 0; i <= 100; i++)
{
label1.Text = i + "%";
progressBar1.PerformStep();
Thread.Sleep(10);
label1.Refresh();
}
}
private void LoadForm()
{
Form2 f2 = new Form2();
f2.Show();
}
}
Then I did reverse that is I loaded progress bar in child thread and loaded f2 on main thread.(See Case 2 Code)
//Code Case2:
case 2 when progress bar is on child thread.
private void button1_Click(object sender, EventArgs e)
{
LoadForm();
Thread th = new Thread(new ThreadStart(StartProgress));
th.Start();
LoadForm();
}
private void StartProgress()
{
progressBar1.Maximum = 100;
progressBar1.Step = 1;
for (int i = 0; i <= 100; i++)
{
label1.Text = i + "%";
progressBar1.PerformStep();
Thread.Sleep(10);
label1.Refresh();
}
}
private void LoadForm()
{
Form2 f2 = new Form2();
f2.Show();
}
but case 2 having 2 problems.
Problem 1: It loads the f2 as usual with flicking.
Problem 2: Cross Thread Opration progressbar1
//Pls suggest how to load the f2 in background and show it after the progress bar is loaded.

If you need to load a secondary window in the background, a better approach would be to load the data in the background of your current UI and then pass that information to the new Window.
public void btnNewWindow_Click(object sender, EventArgs args)
{
BackgroundWorker worker = new BackgroundWorker();
worker.DoWork += WorkerOnDoWork;
worker.ProgressChanged += WorkerOnProgressChanged;
worker.RunWorkerCompleted += WorkerOnRunWorkerCompleted;
worker.RunWorkerAsync();
}
private List<string> _data = new List<string>();
private void WorkerOnRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs runWorkerCompletedEventArgs)
{
//Work has finished. Launch new UI from here.
Form2 f2 = new Form2(_data);
f2.Show();
}
private ProgressBar progressBar1;
void WorkerOnProgressChanged(object sender, ProgressChangedEventArgs e)
{
//Log process here
}
private void WorkerOnDoWork(object sender, DoWorkEventArgs e)
{
//Perform work you need to load the data.
for (int i = 0; i <= 100; i++)
{
Thread.Sleep(50);
_data.Add("Test" + i);
}
}
I put this together real quick in WPF but you should be able to make this work with the same principles. I will reiterate that you shouldn't use a second UI thread. Load the data up front and then pass along to the window when ready and available.

If all you want to do is avoid the flicker, create F2 as hidden, and only show it once its initialization is complete.
It's been a while since I did any Windows Forms programming, but I guess you can show the form in your _Load event handler.

You shouldn't have more than one User Interface (UI) thread. The complexity to keep the data between your interface will be quite difficult and often make the application Not Thread Safe. Which will cause error after error for you.
The primary goal should keep the User Interface (UI) thread responsive. This way as the user interacts with your application the interface is responsive as the application performs computational task.
Here is a great article on keeping your UI thread responsive here.
You may want to note what Microsoft says here:
Note: Not all changes to the UI are necessarily done on the UI thread.
There's a separate render thread that can apply UI changes that won't
affect how input is handled or the basic layout. For example many
animations and transitions that inform users that a UI action has
taken place can actually run on this render thread. But if it's your
code that is changing UI elements somewhere in your pages, it's best
to assume that your code could have the potential to block the UI
thread, unless you're familiar with those APIs or subsystems and know
for certain they don't affect the UI thread.
Update:
I didn't realize you were using Windows Forms, the article listed above is for XAML. You can use this article to help build a responsive UI with computational task here for Windows Forms. (Link is for WPF, you'll need to port for Windows Forms).

Change a button color on button click temporarily in C#

This is in Win forms
On button click I want to change the color of the button temporarily say only for 1 second and then the button color should get back to the previous color. I used lambda expression and timer for this.
private void btn_Read_Click(object sender, EventArgs e)
{
System.Windows.Forms.Timer t1 = new System.Windows.Forms.Timer();
t1.Interval = 1000;
t1.Tick += (src, ee) =>
{
btn_Read.BackColor = Color.Transparent; t1.Stop();
};
t1.Start();
btn_Read.BackColor = Color.YellowGreen;
lvwMessages.Items.Clear();
string strcommand = "AT+CMGL=\"ALL\"";
objShortMessageCollection = ReadSMS(strcommand); // Line wher I am reading messages from the port
foreach (ShortMessage msg in objShortMessageCollection)
{
ListViewItem item = new ListViewItem(new string[] { msg.Sender, msg.Message, msg.Sent, msg.Index });
item.Tag = msg;
lvwMessages.Items.Insert(0, item);
}
if (lvwMessages.Items.Count == 0)
{
status_other.Visible = true;
status_other.Text = "No messages";
lbl_total.Text = "Total: 0";
System.Windows.Forms.Timer timer1 = new System.Windows.Forms.Timer();
timer1.Interval = 2000;
timer1.Tick += (source, ex) => { status_other.Visible = false; timer1.Stop(); };
timer1.Start();
}
else
{
status_other.Visible = false;
chk_selectmsg.Visible = true;
btn_delete.Visible = true;
lbl_total.Text = "Total: " + lvwMessages.Items.Count.ToString(); ;
}
}
Later in this code I am reading the data from serial port, displaying it, etc. The problem is that the button color doesnot change as I click the button. It takes some time and does not give the desired feel I want. Some times doesn't even change the color. What could be the reason?

A simple solution would be using mouse hover event and mouse leave event
Use it this way:
private void btn_Read_MouseHover(object sender, EventArgs e)
{
btn_Read.BackColor = Color.AliceBlue;
}
private void btn_Read_MouseLeave(object sender, EventArgs e)
{
btn_Read.BackColor = Color.AntiqueWhite;
}
This does'nt require any change in your code and definitely will give you the functionality. See if it helps!

you should avoid having work-intensive code on the UI thread
to get the desired effect, sepperate the code for the UI from the code that does the work ...
when the button is clicked, change its appearence and start some background task (threadpool,backgroundworker,etc) that does the work
be aware that you can interact with a control only from the thread it was created on, so to display your data or interact with the UI, you will have to invoke the UI thread (see Control.Invoke(...))
if you have a lot of UI reseting stuff like that, you should think about a timer on the form, to check every let's say 200ms if there is something to be reset/done
you could use a sorted list with tuples (Datetime,delegate) that are executed and removed once the time has come ...

Write the rest of code in thread and fire that thread. this will make your UI responsive and will give you the desired output you want for button. Or use btnedit.Refresh() just after changing color to force button to redraw itself

Form Not Responding when any other operation performed in C#

I have a form (Developed in C# using VS2010) with a Progress Bar.
It's kind of stopwatch form where I fill the progress bar in say 10secs.... As Time elapses, Progress bar fills accordingly.... Means after 5secs, Progress Bar will be filled 50% and so on....
I used a for loop to perform this operation:-
for(int count=0;count<200;count++)
{
progbar.performstep();
progbar.update();
update();
Thread.Sleep(50);
}
I have used Thread.Sleep of 50msec so that progress bar updates smoothly.
For 1sec, it increments in steps.
Problem is if I do anyother operation like Moving this form or even clicking on another icon on desktops makes this form "Not Responding".... But it perfoms the operation and at the end of 10 secs, It regains it's state and shows the pop up indicating 10secs are elapsed with Progress Bar Full.
Thanks for help and Sorry for using such complicated language.
Regards,
Swanand
Update: I solved this problem with the help of Answers below.... One common mistake I got to know is forgetting "Applications.DoEvents()" along with "update()".... If you enter this line, there are less chances of getting "hanged"!

You're performing a long-running operation on the UI thread, which means that the UI "message loop" (responsible for handling events such as user input and updating the screen) doesn't get a chance to run.
You should perform the long-running operation on a different thread (whether one you create yourself or a background thread) and either use BackgroundWorker to easily update your progress bar, or use Control.Invoke/BeginInvoke to marshall a delegate call back to the UI thread when you need to update the UI. (You mustn't update controls from the wrong thread.)
If your only UI interaction is filling in a progress bar, I suggest using BackgroundWorker.
If you're not really doing "real" work, just waiting for time to pass, you could use a System.Windows.Forms.Timer instead of all of this, however. That will "tick" on the UI thread, but won't block the UI thread between ticks. You should only use this if you don't have a lot of work to do though - if it really is just updating a progress bar, not (say) processing a file etc. Note that you shouldn't rely on the timer firing exactly "on time" - you should probably set the position of the progress bar based on the observed time, rather than the observed number of ticks.

You are blocking the UI thread, which means it isn't processing events such as "paint". To do this properly, you should be using something like BackgroundWorker, and just updating the UI from the progress event.
using System;
using System.Windows.Forms;
using System.ComponentModel;
using System.Threading;
static class Program
{
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new MyForm());
}
}
class MyForm : Form
{
Button btn;
BackgroundWorker worker;
ProgressBar bar;
public MyForm()
{
Controls.Add(btn = new Button { Text = "Click me" });
btn.Click += new EventHandler(btn_Click);
Controls.Add(bar = new ProgressBar { Dock = DockStyle.Bottom, Visible = false, Minimum = 0, Maximum = 100 });
worker = new BackgroundWorker { WorkerReportsProgress = true };
worker.ProgressChanged += new ProgressChangedEventHandler(worker_ProgressChanged);
worker.DoWork += new DoWorkEventHandler(worker_DoWork);
worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);
}
void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
bar.Visible = false;
if (e.Error != null)
{
Text = e.Error.Message;
}
else if (e.Cancelled)
{
Text = "cancelled";
}
else
{
Text = e.Result == null ? "complete" : e.Result.ToString();
}
btn.Enabled = true;
}
void worker_DoWork(object sender, DoWorkEventArgs e)
{
for (int count = 0; count < 100; count++)
{
worker.ReportProgress(count);
Thread.Sleep(50);
}
}
void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
bar.Value = e.ProgressPercentage;
}
void btn_Click(object sender, EventArgs e)
{
bar.Value = 0;
bar.Visible = true;
btn.Enabled = false;
worker.RunWorkerAsync();
}
}

You are blocking the Main UI thread. You can use a background worker to do this. You can find more details in MSDN

If you want to run your code you should put this code in a function and call this function with one thread.
public static void fun1()
{
for (int i = 0; i <= 10; i++)
{
Console.Write("This is function1");
Console.Write("\n");
}
}
Thread firstthread = new Thread(new ThreadStart(fun1));
firstthread.Start();
firstthread.suspend();//whenever you want your current control to stop.
b'caz Thread.sleep(100) will stop the whole context not that particular you want..

Answer suggested by Marc will help. Lon running operations can make your application crash or not responsive. I have a blog post related to the usage of the background worker class.
http://midnightprogrammer.net/post/Using-Background-Worker-in-C.aspx