Why WinForm Gets Stuck with BackgroundWorker? - c#

hi guys i tried to copy some files with this Code everything is good and the app will copy files but in copy progress i cant move my app or do anything
i tried to use thread but its not works i also use backgroundWorker but still nothing the only control that doesnt get stuck is progressBar its works fine here is my code :
public Form1()
{
InitializeComponent();
backgroundWorker1.Dispose();
backgroundWorker1.DoWork += BackgroundWorker_DoWork;
backgroundWorker1.RunWorkerCompleted += BackgroundWorker_RunWorkerCompleted;
backgroundWorker1.ProgressChanged += BackgroundWorker_ProgressChanged;
backgroundWorker1.WorkerReportsProgress = true;
backgroundWorker2.DoWork += BackgroundWorker2_DoWork;
backgroundWorker2.WorkerReportsProgress = true;
}
private void BackgroundWorker2_DoWork(object sender, DoWorkEventArgs e)
{
File.Copy(sourcePath, targetPath);
}
private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 0; i < fileSize; i++)
{
int p = (i + 1) * 100 / Convert.ToInt32(fileSize);
backgroundWorker1.ReportProgress(p);
}
}
private void BackgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
}
private void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
lbProgress.Text = e.ProgressPercentage.ToString();
progressBar1.Value = e.ProgressPercentage;
}
private void btnTarget_Click(object sender, EventArgs e)
{
folderBrowser = new FolderBrowserDialog();
if (folderBrowser.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
targetPath += folderBrowser.SelectedPath + #"\" + fileName;
lbTarget.Text = targetPath;
}
}
private void btnSource_Click(object sender, EventArgs e)
{
op = new OpenFileDialog();
if (op.ShowDialog() == DialogResult.OK)
{
sourcePath += op.FileName;
lbSource.Text = sourcePath;
fileInfo = new FileInfo(sourcePath);
fileSize = fileInfo.Length / 1024;
fileName = fileInfo.Name;
MessageBox.Show(string.Format("File size is: {0} KB", fileSize));
}
}
private void btnCopy_Click(object sender, EventArgs e)
{
backgroundWorker1.RunWorkerAsync();
backgroundWorker2.RunWorkerAsync();
}

You're updating the progress bar faster than the UI can update, for every single byte of the file being copied in a tight loop. You're flooding the UI thread with pointless work.
Remove backgroundWorker1, it's not doing anything useful anyway. If you don't have a way to track the progress (which you don't with File.Copy), just use a progress bar without progress (set Style to Marquee).

For testing I created a simple winform application with a button, a label and a background worker and added the following corresponding events:
private void OnBackgroundWorkerDoWork(object sender, DoWorkEventArgs e)
{
var worker = (BackgroundWorker)sender;
for (int i = 0; i < 10; i++)
{
Thread.Sleep(500);
worker.ReportProgress(i * 10);
}
}
private void OnBackgroundWorkerProgressChanged(object sender, ProgressChangedEventArgs e)
{
labelProgress.Text = e.ProgressPercentage.ToString();
}
private void OnBackgroundWorkerRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
labelProgress.Text = "Done";
}
private void OnButtonProgressClick(object sender, System.EventArgs e)
{
backgroundWorker.RunWorkerAsync();
}
Works as expected.

Could You try to update Your DoWork to this:
private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
int mainProgress = 0;
for (int i = 0; i < fileSize; i++)
{
int calculatedProgress = (i + 1) * 100 / Convert.ToInt32(fileSize);
if(calculatedProgress > mainProgress)
{
mainProgress = calculatedProgress;
backgroundWorker1.ReportProgress(mainProgress);
}
}
}
maybe You are doing so many updates that simply Window Thread is all the time updating only progress and don't have a time to make anything else?

Related

The calling thread cannot access this object, because another thread owns it

I am using BackgroundWorker for my WPF application, but what is in the Worker_RunDetection function does not work and there is no interface update from Worker_ProgressShow. Worker_ProgressShow is for updating interface and Worker_RunDetection processes images from path I got from user. This application must search for text in images and tell user how many images have already been processed. What`s wrong?
UPD: I used RunWorkerCompleted and got
The calling thread cannot access this object, because another thread owns it.
Not I use Dispatcher.Invoke, but interface freeze. Progress is a component (ProgressBar).
int numberProcessed = 0;
private void MainForm_ContentRendered(object sender, EventArgs e)
{
worker = new BackgroundWorker();
worker.WorkerReportsProgress = true;
worker.DoWork += Worker_RunDetection;
worker.ProgressChanged += Worker_ProgressShow;
}
private void Worker_ProgressShow(object sender, ProgressChangedEventArgs e)
{
this.Dispatcher.Invoke(() => {
Progress.Value = Convert.ToInt32(e.UserState);
if (Progress.Value % 10 == 0)
LogTextBox.Text += $"\n{Progress.Value} images are processed";
});
}
private void Worker_RunDetection(object sender, DoWorkEventArgs e)
{
this.Dispatcher.Invoke(() => {
foreach (String imageFileName in Directory.GetFiles(PathTextBox.Text))
{
detector = new ImageProcessing(isFolder, imageFileName, pathFolder);
detector.DetectTextOnImage();
numberProcessed++;
(sender as BackgroundWorker).ReportProgress(numberProcessed);
}
});
}
private void StartButton_Click(object sender, RoutedEventArgs e)
{
if (PathTextBox.Text != "")
{
worker.RunWorkerAsync();
}
}
Problem was with the Apth taken from PathTextBox.Text.
It must not reference Controls declared in the UI Thread in the DoWork() handler of a BackGroundWorker.
Everything works fine if the task logic is separated from the UI.
Corrected code:
int numberProcessed = 0;
private void MainForm_ContentRendered(object sender, EventArgs e)
{
worker = new BackgroundWorker();
worker.WorkerReportsProgress = true;
worker.DoWork += Worker_RunDetection;
worker.ProgressChanged += Worker_ProgressShow;
}
private void Worker_ProgressShow(object sender, ProgressChangedEventArgs e)
{
Progress.Value = Convert.ToInt32(numberProcessed);
if (Progress.Value % 10 == 0)
LogTextBox.Text += $"\n{Progress.Value} images are processed";
}
private void Worker_RunDetection(object sender, DoWorkEventArgs e)
{
foreach (String imageFileName in Directory.GetFiles(e.Argument.ToString()))
{
detector = new ImageProcessing(isFolder, imageFileName, pathFolder);
detector.DetectTextOnImage();
numberProcessed++;
(sender as BackgroundWorker).ReportProgress(numberProcessed);
}
}

How to run a progress bar on a timer - c#

I want to run a progress bar on a form through the use of a timer.
I have tried multiple ways and have not been able to get it to work.
I hope someone here can help me with this.
private void SplashScreen_Load(object sender, EventArgs e)
{
splashScreenTimer.Enabled = true;
splashScreenTimer.Start();
splashScreenTimer.Interval = 1000;
progressBar.Maximum = 100;
splashScreenTimer.Tick += new EventHandler(timer1_Tick);
}
private void timer_Tick(object sender, EventArgs e)
{
if (progressBar.Value != 10)
{
progressBar.Value++;
}
else
{
splashScreenTimer.Stop();
}
}
you are assigning event_handler like
splashScreenTimer.Tick += new EventHandler(timer1_Tick);
and you are changing the progressBar value in
private void timer_Tick(object sender, EventArgs e)
{
if (progressBar.Value != 10)
{
progressBar.Value++;
}
else
{
splashScreenTimer.Stop();
}
}
change event handler to
splashScreenTimer.Tick += new EventHandler(timer_Tick);
or move codes to the other event handler timer1_Tick which should be in your form
For running the progressBar full in 4 seconds you can do like this
private void Form1_Load(object sender, EventArgs e)
{
splashScreenTimer.Enabled = true;
splashScreenTimer.Start();
splashScreenTimer.Interval = 30;
progressBar.Maximum = 100;
splashScreenTimer.Tick += new EventHandler(timer_Tick);
}
int waitingTime = 0;
private void timer_Tick(object sender, EventArgs e)
{
if (progressBar.Value < 100)
{
progressBar.Value++;
}
else
{
if (waitingTime++ > 35)
this.Close();
}
}

How to make Trackbar works while media is playing

I am working on a simple mediaplayer application. It works great but I want to add some extra features. I have added a trackbar control.How can i set trackbar length the same as the music's length ?
Like if the song is halfways the trackbars halfways.This is what I have so far
string[] files, indexed_files;
private void button3_Click(object sender, EventArgs e)
{
OpenFileDialog ofd = new OpenFileDialog();
ofd.Multiselect = true;
if (ofd.ShowDialog() == DialogResult.OK) {
files = ofd.SafeFileNames;
indexed_files = ofd.FileNames;
for (int i = 0; i < files.Length; i++)
{
listBox1.Items.Add(files[i]);
}
}
button4.Enabled = true;
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
axWindowsMediaPlayer1.URL = indexed_files[listBox1.SelectedIndex];
progressBar1.Maximum =(int) axWindowsMediaPlayer1.currentMedia.duration;
axWindowsMediaPlayer1.PlayStateChange += axWindowsMediaPlayer1_PlayStateChange;
}
void axWindowsMediaPlayer1_PlayStateChange(object sender, AxWMPLib._WMPOCXEvents_PlayStateChangeEvent e)
{
trackBar1.Value = (int)axWindowsMediaPlayer1.Ctlcontrols.currentPosition;
}
int index = 0;
private void button4_Click(object sender, EventArgs e)
{
if (listBox1.Items.Count != 0) {
axWindowsMediaPlayer1.URL = indexed_files[index];
trackBar1.Maximum = (int)axWindowsMediaPlayer1.currentMedia.duration;
index++;
index = (index % listBox1.Items.Count);
}
}
This will bring you the desired outcome.In my example i just placed the url in the form load for demonstration purposes.The openstatechanged event its to set the trackbar maximum since you need to wait for the player to load the file,after that the code its pretty self-explanatory:
public partial class Form1 : Form
{
Timer t;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
axWindowsMediaPlayer1.URL = "YourUrlHere";
t = new Timer();
t.Interval = 1000;
t.Tick += new EventHandler(t_Tick);
}
void t_Tick(object sender, EventArgs e)
{
trackBar1.Value = (int)this.axWindowsMediaPlayer1.Ctlcontrols.currentPosition;
}
private void axWindowsMediaPlayer1_OpenStateChange(object sender, AxWMPLib._WMPOCXEvents_OpenStateChangeEvent e)
{
if (axWindowsMediaPlayer1.openState == WMPLib.WMPOpenState.wmposMediaOpen)
{
trackBar1.Maximum = (int)axWindowsMediaPlayer1.currentMedia.duration;
t.Start();
}
}
}
Yes its a timer:),and probably it is best to set it bellow 1000 for reasons of delay.
So you should now add a timer and insert the following code in timer Tick event handler:
trackbar.Value = this.axWindowsMediaPlayer1.ctlControls.CurrentPosition;

Running a method in BackGroundWorker and Showing ProgressBar

What I want is when some method is doing some task UI keeps itself active and I want to show the progress of the work in a progress-bar.
I have a method, a BackGroundWorker and a Progressbar. I want to call the method when BackGroundWorker starts running and show the progress. The method contains a loop. So, it can report the progress.
So, what can be done?
private void Form1_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'dataSet1.TBLMARKET' table. You can move, or remove it, as needed.
myBGWorker.WorkerReportsProgress = true;
}
private void myBGWorker_DoWork(object sender, DoWorkEventArgs e)
{
parseFiles();
}
private void myBGWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
myProgressBar.Value = e.ProgressPercentage;
}
private void myBGWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
MessageBox.Show("Done");
}
private void parseButton_Click(object sender, EventArgs e)
{
myBGWorker.RunWorkerAsync();
}
public void parseFiles()
{
for()
{
//parsing
myBGWorker.ReportProgress(...);
}
}
But it's not working. The Progressbar is not updating. Only a small progress is showing after the MessageBox "Done".
Instead of using one ParseFiles method (which should depend on myBGWorker) use loop and method which parse one file. Report progress percentage in that loop:
private void parseButton_Click(object sender, EventArgs e)
{
parseButton.Enabled = false;
myBGWorker.RunWorkerAsync();
}
private void myBGWorker_DoWork(object sender, DoWorkEventArgs e)
{
for(int i = 0; i < filesCount; i++)
{
ParseSingleFile(); // pass filename here
int percentage = (i + 1) * 100 / filesCount;
myBGWorker.ReportProgress(percentage);
}
}
void myBGWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
myProgressBar.Value = e.ProgressPercentage;
}
void myBGWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
parseButton.Enabled = true;
MessageBox.Show("Done");
}
To. soham.m17
using with sender argument
private void myBGWorker_DoWork(object sender, DoWorkEventArgs e)
{
var worker = sender as BackgroundWorker;
for(int i = 0; i < filesCount; i++)
{
ParseSingleFile(); // pass filename here
int percentage = (i + 1) * 100 / filesCount;
worker.ReportProgress(percentage); // use not myBGWorker but worker from sender
}
}
I am sorry about the question. Actually the code works fine. It was not showing the Progressbar as the argument in myBGWorker.ReportProgress() was fraction and not percentage. So, it was not showing it. Sorry for the inconvenience.
Moderator may delete this thread. Otherwise it can be a tutorial for others.

Background Worker Issue

Edit: I solved the problem by creating the background worker by creating it in code instead of dragging and dropping in design.
Now I know how to use a background worker.
Question
It's my first time using a BGWorker, so here's my issue...
The cursor doesn't change to "Wait".
The progress bar doesn't update.
RunWorkerCompleted isn't invoked.
But the textbox does update.
Am I doing something wrong ?
The Code
using System;
using System.ComponentModel;
using System.Windows.Forms;
namespace BGWorker
{
public partial class Main : Form
{
public Main()
{
InitializeComponent();
progressBar1.Minimum = 0;
progressBar1.Value = 0;
progressBar1.Maximum = 100;
}
private void button1_Click(object sender, EventArgs e)
{
Cursor.Current = Cursors.WaitCursor;
backgroundWorker1.RunWorkerAsync();
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 1; i <= 100; i++)
{
textBox1.AppendText(i.ToString());
textBox1.AppendText("\n");
backgroundWorker1.ReportProgress(i);
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error != null)
{
label1.Text = e.Error.Message;
}
else
{
label1.Text = "All Done !";
Cursor.Current = Cursors.Default;
}
}
}
}
Thanks.
I agree with pst.
Always create your worker in the code behind - dragging and dropping on the form is never a good idea
You never access UI elements from the DoWork. You can only do this from the ReportProgress and RunWorker Completed Events
Your if statement segment should contain your most common path with the least common path in the else.
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
StringBuilder sb = new StringBuilder();
for (int i = 1; i <= 100; i++)
{
sb.AppendLine(i.ToString());
backgroundWorker1.ReportProgress(i);
}
e.Result = sb.ToString();
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error == null)
{
textbox1.Text = e.Result.ToString();
label1.Text = "All Done !";
Cursor.Current = Cursors.Default;
}
else
{
label1.Text = e.Error.Message;
}
}

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