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Updating progressbar through backgroundworker in method

My programm (in C# using Windows Forms) is reading and parsing large amounts of Data and I'm using a Backgroundworker which calls those global methods (reading and parsing). I'd like to keep the user updated on how long it's going to take, so the Backgroundworker is supposed to display what action its doing and has a progressbar that should fill for every individual action too.
Unfortunately, I can't get it to work, as the progressbar just doesn't update at all and just stays empty.
Here is what I have so far:
private void InitializeBackgroundWorker()
{
backgroundWorker1.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);
backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);
backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
}
private void buttonParse_Click(object sender, EventArgs e)
{
DescriptionLabel.Visible = true;
progressBar1.Visible = true;
backgroundWorker1.RunWorkerAsync();
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
Methods.ParsePerfusionData(backgroundWorker1); //Also tried using 'worker' here, but didnt work either
}
And in the method it looks like that:
public static void ParsePerfusionData(BackgroundWorker worker)
{
for (int i = 2; i < Globals.DataList.Count; i++)
{
worker.ReportProgress(i / amount * 100);
rest of the code etc.
}
}
Can I not use a backgroundworker in a global method like that? Thanks in advance!

When i < amount then i / amount * 100 = 0 * 100 = 0.
Simply use i * 100 / amount instead.
Also make sure backgroundWorker1.WorkerReportsProgress = true

You can only report progress between distinct operations. That means either:
using a very modern class that supports this level of reporting. Such a classs might not exist for your case.
reverse engineering parts of the code down to the loop you want to make reporting on. Usually the loop that itterates over files or the like.
GUI updates must be contained to RunWorkerCompelted and ProgressReport events. And depending on how often updates happen, ProgressReport may have to be kept to only updating a progress bar.
Here some old code I wrote with BackgroundWorker wich should get you started:
#region Primenumbers
private void btnPrimStart_Click(object sender, EventArgs e)
{
if (!bgwPrim.IsBusy)
{
//Prepare ProgressBar and Textbox
int temp = (int)nudPrim.Value;
pgbPrim.Maximum = temp;
tbPrim.Text = "";
//Start processing
bgwPrim.RunWorkerAsync(temp);
}
}
private void btnPrimCancel_Click(object sender, EventArgs e)
{
if (bgwPrim.IsBusy)
{
bgwPrim.CancelAsync();
}
}
private void bgwPrim_DoWork(object sender, DoWorkEventArgs e)
{
int highestToCheck = (int)e.Argument;
//Get a reference to the BackgroundWorker running this code
//for Progress Updates and Cancelation checking
BackgroundWorker thisWorker = (BackgroundWorker)sender;
//Create the list that stores the results and is returned by DoWork
List<int> Primes = new List<int>();
//Check all uneven numbers between 1 and whatever the user choose as upper limit
for(int PrimeCandidate=1; PrimeCandidate < highestToCheck; PrimeCandidate+=2)
{
//Report progress
thisWorker.ReportProgress(PrimeCandidate);
bool isNoPrime = false;
//Check if the Cancelation was requested during the last loop
if (thisWorker.CancellationPending)
{
//Tell the Backgroundworker you are canceling and exit the for-loop
e.Cancel = true;
break;
}
//Determin if this is a Prime Number
for (int j = 3; j < PrimeCandidate && !isNoPrime; j += 2)
{
if (PrimeCandidate % j == 0)
isNoPrime = true;
}
if (!isNoPrime)
Primes.Add(PrimeCandidate);
}
//Tell the progress bar you are finished
thisWorker.ReportProgress(highestToCheck);
//Save Return Value
e.Result = Primes.ToArray();
}
private void bgwPrim_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
pgbPrim.Value = e.ProgressPercentage;
}
private void bgwPrim_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
pgbPrim.Value = pgbPrim.Maximum;
this.Refresh();
if (!e.Cancelled && e.Error == null)
{
//Show the Result
int[] Primes = (int[])e.Result;
StringBuilder sbOutput = new StringBuilder();
foreach (int Prim in Primes)
{
sbOutput.Append(Prim.ToString() + Environment.NewLine);
}
tbPrim.Text = sbOutput.ToString();
}
else
{
tbPrim.Text = "Operation canceled by user or Exception";
}
}
#endregion

Background worker Run worker completed executes in the middle of do work when run for the second time

I have background worker where I am getting some callback in a thread and I am updating the UI and the progress bar as the states change. Currently there are 3 states 1) Cartridgr Drawer Closed 2) Processing 3) Processed.
First Time when the application starts everything works fine. The Run Worker Completed fires after the Processed state and I am launching an other success window through an event.
But for the second when I rerun the workflow without closing the application, I get the success Window when the worker still says Processing. Why is that also the remaining time that I am updating behaves incorrectly. Please help. (Please see the DoWork event Thread th I guess thats the issue).
//This method is a RelayCommand thats called on some button click
private void StartCurrentRun(bool obj)
{
this.worker = new BackgroundWorker();
this.worker.WorkerReportsProgress = true;
this.worker.WorkerSupportsCancellation = true;
StartTimer();
PropertyCallBackChangedInstance.PropertyChanged -= PropertyCallBackChangedInstance_PropertyChanged;
WhenCancelledBlurVolumesGrid = false;
this.worker.DoWork += this.DoWork;
this.worker.ProgressChanged += this.ProgressChanged;
this.worker.RunWorkerCompleted += Worker_RunWorkerCompleted;
IsLiveProgress = true;
this.worker.RunWorkerAsync();
}
private void DoWork(object sender, DoWorkEventArgs e)
{
int OriginalTimeRemaining = SelectedVolumeEstimatedTime();
int TotalPrecentagebasedOnNumberOfStates = 50;
int PercentProgress = 100 / TotalPrecentagebasedOnNumberOfStates;
CurrentCartridgeStatus status = CurrentCartridgeStatus.NotProcessed;
var instance = ConnectToInstrument.InstrumentConnectionInstance;
instance.InitalizeRun();
Thread th = new Thread(() =>
{
PropertyCallBackChangedInstance.PropertyChanged += PropertyCallBackChangedInstance_PropertyChanged;
});
th.Start();
Thread th2 = new Thread(() =>
{
while (PropertyCallBackChangedInstance.CurrentCartridgeStatusChanged != CurrentCartridgeStatus.Processed)
{
lock (_objectForThread2)
{
if (OriginalTimeRemaining > 0)
{
OriginalTimeRemaining -= 2;
}
var time = TimeSpan.FromSeconds(OriginalTimeRemaining);
EstimatedTimeRemaining = string.Format("{0:00}:{1:00}:{2:00}",
time.Hours,
time.Minutes,
time.Seconds);
OnPropertyChanged("EstimatedTimeRemaining");
}
Thread.Sleep(2000);
}
});
th2.Start();
int counter = 0;
for (int i = 0; i < PercentProgress; i++)
{
//Keep checking to see if the Run is cancelled
if (WhenCancelledBlurVolumesGrid) //That means the run is cancelled
{
if (worker.CancellationPending)
{
e.Cancel = true;
worker.CancelAsync();
}
}
for (int j = counter; j <= TotalPrecentagebasedOnNumberOfStates; j++)
{
worker.ReportProgress(Math.Min(j, 100));
if (status != CurrentCartridgeStatus.Processed)
{
Thread.Sleep(55);
}
}
counter = 50;
TotalPrecentagebasedOnNumberOfStates += 50;
}
th.Join();
th2.Join();
}
private void PropertyCallBackChangedInstance_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (e.PropertyName == "CurrentCartridgeStatusChanged")
{
var value = sender as InstrumentCallBackProperties;
CurrentStatus = EnumExtensions.GetDescription(value.CurrentCartridgeStatusChanged);
}
}
private void ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.ProgressValue = e.ProgressPercentage;
}
private void Worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
EstimatedTimeRemaining = "00:00:00";
stopWatch.Stop();
timer.Stop();
Messenger.Default.Send(new NotificationMessage("RunComplete"));
if (e.Cancelled)
{
SelectedVolume = string.Empty;
}
else
{
IsLiveProgress = false;
if (IsRunSuccessfullyComplete != null && !WhenCancelledBlurVolumesGrid) //This indicates that Success will only open when the run is complete
{
IsRunSuccessfullyComplete(NoErrors);//This event opens the success window from a different page
}
WhenCancelledBlurVolumesGrid = true;
}
//I have some Dispose method that i am trying to do after the first run.
public void Dispose()
{
if (this.worker != null)
{
this.ProgressValue = 0;
this.worker.CancelAsync();
this.worker.Dispose();
this.worker = null;
timer = null;
stopWatch = null;
TimeElapsed = string.Empty;
}
}

Windows form progress bar not working?

I have a button .It will open a file and process a file .I want to show the progress bar while processing the file .
when i am doing .its working
public MainframeDataExchangeTool()
{
InitializeComponent();
_ProgressBar.Style = ProgressBarStyle.Marquee;
_ProgressBar.Visible = false;
_Random = new Random();
InitializeBackgroundWorker();
}
private void InitializeBackgroundWorker()
{
_BackgroundWorker = new BackgroundWorker();
_BackgroundWorker.WorkerReportsProgress = true;
_BackgroundWorker.DoWork += (sender, e) => ((MethodInvoker)e.Argument).Invoke();
_BackgroundWorker.ProgressChanged += (sender, e) =>
{
_ProgressBar.Style = ProgressBarStyle.Continuous;
_ProgressBar.Value = e.ProgressPercentage;
};
_BackgroundWorker.RunWorkerCompleted += (sender, e) =>
{
if (_ProgressBar.Style == ProgressBarStyle.Marquee)
{
_ProgressBar.Visible = false;
}
};
}
In my button click i am doing
private void btnOpenScriptFile_Click(object sender, EventArgs e)
{
try
{
loadScriptFlDlg.Filter = Constants.SCRIPT_FILE_FILTER;
loadScriptFlDlg.FilterIndex = 3;
loadScriptFlDlg.RestoreDirectory = true;
loadScriptFlDlg.FileName = string.Empty;
DialogResult objDialogResult = loadScriptFlDlg.ShowDialog();
if (objDialogResult.Equals(DialogResult.OK))
{
_BackgroundWorker.RunWorkerAsync(new MethodInvoker(() =>
{
_ProgressBar.BeginInvoke(new MethodInvoker(() => _ProgressBar.Visible = true));
for (int i = 0; i < 100; i++)
{
Thread.Sleep(10);
_BackgroundWorker.ReportProgress(i);
}
}));
EnableDisableControls("OpenScript");
string strScriptError = LoadScriptFromFile(loadScriptFlDlg.FileName);///loading will taking time but progress bar not showing
Basically progress bar is showing at the end of data load but not while loading the data

You cannot see the progress as UI thread cannot update UI because it is busy loading your file. You must call LoadScriptFromFile from the background worker and keep UI thread free to process events and update UI.

I used this in my project with 2 methode (exemple):
1* Invoke(new Action(() => _ProgressBar.Visible = true));
2* or use Application.DoEvents() after your _BackgroundWorker.ReportProgress(i);

Surprised the compiler didn't throw a hissy fit...because you need an extra }.
You open 4 levels of nesting, but only close 3.
I have modified your code as shown below:
private void btnOpenScriptFile_Click(object sender, EventArgs e)
{
try
{
if (objDialogResult.Equals(DialogResult.OK))
{
_ProgressBar.Style = ProgressBarStyle.Marquee;
_ProgressBar.BeginInvoke(new MethodInvoker(() => _ProgressBar.Visible = true));
for (int i = 0; i < 100; i++)
{
Thread.Sleep(10);
_ProgressBar.BeginInvoke(new Action(() => _ProgressBar.Value = i));
//Process my file here
}
}
}
Catch
{
}
}
I would always suggest reducing the number of empty lines, for readability.
I also find that the 'allman' style bracketing is easiest to debug.
But as always, each to his own.
EDIT:
After OP editted code:
Try adding:
application.doevents()
after your:
_BackgroundWorker.ReportProgress(i);
Why? The code will stay in the for loop until completes. By doing 'doevents' you are telling it to update externally, before the next loop.
Without the 'doevents' i guess you would see 0 and 100 only.

Simply do something like this with a BackgroundWorker (bgw).
private void MyMethod()
{
bgw.RunWorkerAsync(); //this calls the DoWork event
}
private void bgw_DoWork(object sender, DoWorkEventArgs e)
{
//Expensive task
//Calculate how far you through your task (ie has read X of Y bytes of file)
bgw.ReportProgress(myInteger);
}
private void bgw_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
myProgressBar.Value = e.ProgressPercentage;
}
Make sure you set the BackgroundWorker's "WorkerReportsProgress" property to True!

C#, Constantly monitor battery level

I am designing a program that depends on monitoring the battery level of the computer.
This is the C# code I am using:
PowerStatus pw = SystemInformation.PowerStatus;
if (pw.BatteryLifeRemaining >= 75)
{
//Do stuff here
}
My failed attempt of the while statement, it uses all the CPU which is undesirable.
int i = 1;
while (i == 1)
{
if (pw.BatteryLifeRemaining >= 75)
{
//Do stuff here
}
}
How do I monitor this constantly with an infinite loop so that when it reaches 75% it will execute some code.

Try Timer:
public class Monitoring
{
System.Windows.Forms.Timer timer1 = new System.Windows.Forms.Timer();
public Monitoring()
{
timer1.Interval = 1000; //Period of Tick
timer1.Tick += timer1_Tick;
}
private void timer1_Tick(object sender, EventArgs e)
{
CheckBatteryStatus();
}
private void CheckBatteryStatus()
{
PowerStatus pw = SystemInformation.PowerStatus;
if (pw.BatteryLifeRemaining >= 75)
{
//Do stuff here
}
}
}
UPDATE:
There is another way to do your task complete. You can use SystemEvents.PowerModeChanged.
Call it and wait for changes, monitor the changes occured then do your stuff.
static void SystemEvents_PowerModeChanged(object sender, Microsoft.Win32.PowerModeChangedEventArgs e)
{
if (e.Mode == Microsoft.Win32.PowerModes.StatusChange)
{
if (pw.BatteryLifeRemaining >= 75)
{
//Do stuff here
}
}
}

While loop will cause your UI to response poor and the application will get crashed. You can solve this by using many ways. Please check out the below code snippet will help your needs.
public delegate void DoAsync();
private void button1_Click(object sender, EventArgs e)
{
DoAsync async = new DoAsync(GetBatteryDetails);
async.BeginInvoke(null, null);
}
public void GetBatteryDetails()
{
int i = 0;
PowerStatus ps = SystemInformation.PowerStatus;
while (true)
{
if (this.InvokeRequired)
this.Invoke(new Action(() => this.Text = ps.BatteryLifePercent.ToString() + i.ToString()));
else
this.Text = ps.BatteryLifePercent.ToString() + i.ToString();
i++;
}
}

BatteryChargeStatus.Text = SystemInformation.PowerStatus.BatteryChargeStatus.ToString();
BatteryFullLifetime.Text = SystemInformation.PowerStatus.BatteryFullLifetime.ToString();
BatteryLifePercent.Text = SystemInformation.PowerStatus.BatteryLifePercent.ToString();
BatteryLifeRemaining.Text = SystemInformation.PowerStatus.BatteryLifeRemaining.ToString();
PowerLineStatus.Text = SystemInformation.PowerStatus.PowerLineStatus.ToString();
If you want to perform some operation just convert these string values into the integer.

How to avoid freezing of GUI?

i have a code which is like this :
private void testToolStripMenuItem_Click(object sender, EventArgs e)
{
toolStripStatusLabel1.Text = " Device Testing...";
positive = false;
clearsensors_gui();
datarec = false;
cmd = 04;
datarec = serialport_FT(0, 1);
if (datarec)
{
char ab = Convert.ToChar(rec_data[1]);
//MessageBox.Show("\n" + ab + "\n");
int cab = Convert.ToInt16(ab);
int cabc1 = cab & 1;
int cabc2 = cab & 2;
int cabc3 = cab & 4;
int cabc4 = cab & 8;
int cabc5 = cab & 16;
int cabc6 = cab & 32;
if (cabc1 == 1)
ovalShape1.FillColor = Color.Green;
else
ovalShape1.FillColor = Color.Red;
if (cabc2 == 2)
ovalShape2.FillColor = Color.Green;
else
ovalShape2.FillColor = Color.Red;
if (cabc3 == 4)
ovalShape3.FillColor = Color.Green;
else
ovalShape3.FillColor = Color.Red;
if (cabc4 == 8)
ovalShape4.FillColor = Color.Green;
else
ovalShape4.FillColor = Color.Red;
if (cabc5 == 16)
ovalShape5.FillColor = Color.Green;
else
ovalShape5.FillColor = Color.Red;
if (cabc6 == 32)
ovalShape6.FillColor = Color.Green;
else
ovalShape6.FillColor = Color.Red;
toolStripStatusLabel1.Text = " Device Tested";
}
else
{
toolStripStatusLabel1.Text = "Try Again or Communication With Device Failure....";
}
}
the above code is to read a the sensors i.e datarec = serialport_FT(0, 1); function provides me a sensor output at the GUI side which'll be later depicted with red\green ovalShapeX(1-6)
Question: datarec = serialport_FT(0, 1); this function takes liltime and so the GUI freezes till that time how to avoid this?
i tried using background worker but didn't get where to put this whole process
also encountered with cross-threaded operation error when it goes to ovalShape and changing its properties.
I'm not getting what part of the function to be used in the background and where and when to get back to the 1st thread
please help me to use backgroundworker or use invoke if i have to use Threading

You could do something like this:
toolStripStatusLabel1.Text = " Device Testing...";
positive = false;
clearsensors_gui();
datarec = false;
cmd = 04;
BackgroundWorker worker = new BackgroundWorker();
worker.DoWork += delegate(object s, DoWorkEventArgs args)
{
// Will be run on background thread
args.Result = serialport_FT(0, 1);
};
worker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args)
{
bool result = (bool)args.Result;
if (result)
{
// Do your UI updates here
}
};
worker.RunWorkerAsync();
One improvement could be to combine datarec and rec_data as a Tuple in args.Result.

In the background worker you use the DoWork event.
worker.DoWork += new DoWorkEventHandler(yourEventHandler);
void yourEventHandler(object sender, DoWorkEventArgs e)
{
//your work here
}

As you are using WinForms, here is a great MSDN article to get you started with using multiple threads in an application: Give Your .NET-based Application a Fast and Responsive UI with Multiple Threads
The article is 'a few days old', but the principles remain absolutely valid today.
If you are working in a .NET 4.x version, you can also use the Task Parallel Library to make working with multiple threads easier.
The upcoming .NET 4.5 also offers the even more comfortable await and asyc keywords: Asynchronous Programming with Async and Await.

Put this in a background thread as you already tried (or better yet, a Task), but be careful to call GUI-related operations only through Control.Invoke (for WinForms) or Dispatcher.Invoke (for WPF).

Used a Label which updates in real time as the task progresses. You can try this code [using BackGroundWorker]. Look at DoWork where you put your business logic [See BusinessClass usage in the code], then see the ProgressChanged where the background task signals the UI in real time as the task progresses & finally see the RunWorkerCompleted where you handle code after task completion, error or cancellation.
using System.ComponentModel;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form3 : Form
{
private BackgroundWorker _worker;
BusinessClass _biz = new BusinessClass();
public Form3()
{
InitializeComponent();
InitWorker();
}
private void InitWorker()
{
if (_worker != null)
{
_worker.Dispose();
}
_worker = new BackgroundWorker
{
WorkerReportsProgress = true,
WorkerSupportsCancellation = true
};
_worker.DoWork += DoWork;
_worker.RunWorkerCompleted += RunWorkerCompleted;
_worker.ProgressChanged += ProgressChanged;
_worker.RunWorkerAsync();
}
void DoWork(object sender, DoWorkEventArgs e)
{
int highestPercentageReached = 0;
if (_worker.CancellationPending)
{
e.Cancel = true;
}
else
{
double i = 0.0d;
int junk = 0;
for (i = 0; i <= 199990000; i++)
{
int result = _biz.MyFunction(junk);
junk++;
// Report progress as a percentage of the total task.
var percentComplete = (int)(i / 199990000 * 100);
if (percentComplete > highestPercentageReached)
{
highestPercentageReached = percentComplete;
// note I can pass the business class result also and display the same in the LABEL
_worker.ReportProgress(percentComplete, result);
_worker.CancelAsync();
}
}
}
}
void RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Cancelled)
{
// Display some message to the user that task has been
// cancelled
}
else if (e.Error != null)
{
// Do something with the error
}
}
void ProgressChanged(object sender, ProgressChangedEventArgs e)
{
label1.Text = string.Format("Result {0}: Percent {1}",e.UserState, e.ProgressPercentage);
}
}
public class BusinessClass
{
public int MyFunction(int input)
{
return input+10;
}
}
}