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UI unresponsive + progress bar not working while using backgroundworker c#

I'm working on a WPF application in Visual Studio, I need to download a large file and extract it in my code. Someone recommended that I use background workers, but now when I try to increase the value on my progress bar it doesn't work... Can anyone help?
public void InstallVersion(string version)
{
string location = File.ReadAllText(#"C:\Users\" + Environment.UserName + #"\AppData\Roaming\MidnightFallsLauncher\data\locator.txt");
location = location + #"\Versions\" + version;
if (File.Exists(location + ".zip"))
File.Delete(location + ".zip");
if (Directory.Exists(location))
{
DirectoryInfo di = new DirectoryInfo(location);
foreach (FileInfo file in di.GetFiles())
{
file.Delete();
}
foreach (DirectoryInfo dir in di.GetDirectories())
{
dir.Delete(true);
}
}
if (!myWorker.IsBusy)
{
myWorker.RunWorkerAsync();
}
}
And here is my worker code
public MainWindow()
{
InitializeComponent();
myWorker.DoWork += new DoWorkEventHandler(myWorker_DoWork);
myWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(myWorker_RunWorkerCompleted);
myWorker.ProgressChanged += new ProgressChangedEventHandler(myWorker_ProgressChanged);
myWorker.WorkerReportsProgress = true;
myWorker.WorkerSupportsCancellation = true;
}
protected void myWorker_DoWork(object sender, DoWorkEventArgs e)
{
string location = File.ReadAllText(#"C:\Users\" + Environment.UserName + #"\AppData\Roaming\MidnightFallsLauncher\data\locator.txt");
location = location + #"\Versions\" + Version;
WebClient Client = new WebClient();
string url = "";
string content = "";
string downloadlink = "";
List<string> availibleVersions = new List<string>();
List<string> versionDownload = new List<string>();
url = "https://midnightfalls.glitch.me/versions.html";
content = Client.DownloadString(url);
foreach (string line in content.Split(new string[] { "<br>", "<br />" }, StringSplitOptions.None))
{
if (line.Contains("0"))
{
availibleVersions.Add(line);
}
}
url = "https://midnightfalls.glitch.me/versionslink.html";
content = Client.DownloadString(url);
foreach (string line in content.Split(new string[] { "<br>", "<br />" }, StringSplitOptions.None))
{
if (line.Contains("https"))
{
versionDownload.Add(line);
}
}
for (var i = 0; i < availibleVersions.Count; i++)
{
if (availibleVersions[i] == Version)
{
downloadlink = versionDownload[i];
}
}
Client.DownloadFile(downloadlink, location + ".zip");
ZipFile.ExtractToDirectory(location + ".zip", location);
File.Delete(location + ".zip");
RunGame(Version);
}
protected void myWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
}
protected void myWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.Dispatcher.Invoke(() =>
{
progress.Value += 10;
});
}
Also, while my worker is running, the UI freezes... I'm pretty sure that's not meant to happen.
EDIT:
The UI is now updating but the progress bar still doesnt work...

It looks like the problem is that the main thread is constantly working while the background worker is doing its work:
while (this.myWorker.IsBusy)
{
this.Dispatcher.Invoke(() =>
{
progress.Value += 10;
});
}
means that your main thread is constantly doing stuff while the background job is working, which is why the UI doesn't update.
You need to move the progress update to the background worker (where you could also set a value that actually makes some sense, e.g. to indicate how many of the 'availableVersion's you have downloaded).
Hope that makes sense.
EDIT:
Suppose we'll put all the code directly in the view, so assume we have a progress bar named 'progressBar' and a button named 'btnStart' (which kicks of the backgroundworker).
Here's the codebehind:
private BackgroundWorker worker;
public MainWindow()
{
InitializeComponent();
this.worker = new BackgroundWorker();
this.worker.DoWork += new DoWorkEventHandler(myWorker_DoWork);
this.worker.RunWorkerCompleted += new
RunWorkerCompletedEventHandler(myWorker_RunWorkerCompleted);
this.worker.ProgressChanged += new
ProgressChangedEventHandler(myWorker_ProgressChanged);
this.worker.WorkerReportsProgress = true;
this.worker.WorkerSupportsCancellation = true;
}
private void myWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.progressBar.Value = e.ProgressPercentage;
}
private void myWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
// Whatever you need to do when finished here (alert, update a label, etc.)
}
private void myWorker_DoWork(object sender, DoWorkEventArgs e)
{
// Just loop and report new progress. Sleep a little in between each
// progress update so that it isn't over before we have a chance to see it.
for(int i=0;i<100;i++)
{
Thread.Sleep(200);
this.worker.ReportProgress(i);
}
}
private void btnStart_Click(object sender, RoutedEventArgs e)
{
this.worker.RunWorkerAsync();
}
What happens is that the background worker fires an event notifying that progress has changed.
The main thread has a handle on that event, and updates the progress bar.
Since it's a background worker you don't need to use Dispatcher.Invoke - this is already taken care of.
Hope the example clarifies things for you.

I'm pretty sure you're blocking right here:
while (this.myWorker.IsBusy)
{
this.Dispatcher.Invoke(() =>
{
progress.Value += 10;
});
}
You should be calling ReportProgress on your BackgroundWorker instance within your myWorker_DoWork method.
Also, if you're using .NET 4.5 or later, you can dump the BackgroundWorker entirely and rewrite this code using the async/await pattern.

I'm using a webclient to download files inside a backgroundworker's "DoWork"

I could use only the web client I guess.
But now I'm using a BackgroundWorker thread and the web client for downloading files.
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
var v = lines.Where(s => s.Contains("Name")).Select(s => s.Substring(15));
var q = lines.Where(s => s.Contains("Code")).Select(s => s.Substring(15));
var r = q.Where(c => c == "is").Concat(q.Where(c => c != "is"));
var p = v.Where(c => c == "Israel").Concat(v.Where(c => c != "Israel"));
var n = r.Count();
int i = 0;
var results = p.ToList();
using (var client = new WebClient())
{
foreach (var c in r)
{
string filesPath = defaultPath + "\\Countries" + "\\" + results[i] + "\\" + results[i] + ".gif";
Uri uri = new Uri("http://api.sat24.com/animated/" + c + "/infraPolair/1/JerusalemStandardTime/1897199");
client.DownloadFile(uri, filesPath);
backgroundWorker1.ReportProgress(i * 100 / n, results[i]);
++i;
}
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
try
{
progressBar1.Value = e.ProgressPercentage;
label1.Text = e.ProgressPercentage.ToString() + "%";
label2.Text = e.UserState.ToString();
}
catch (Exception ex)
{
string ttt = ex.ToString();
}
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error == null)
{
progressBar1.Value = 100;
}
else
{
}
}
private void timer1_Tick(object sender, EventArgs e)
{
DirectoryInfo dir1 = new DirectoryInfo(#"C:\Users\Chocolade\AppData\Local\SatellitesImagesDownloads\SatellitesImagesDownloads\Countries\");
fi = dir1.GetFiles("*.gif", SearchOption.AllDirectories);
foreach (FileInfo finfo in fi)
{
if (fi.Length > 0 && finfo.Length > 0)
{
timer1.Enabled = false;
pictureBox1.Load(finfo.FullName);
listView1.Items[0].Checked = true;
}
}
}
The first problem as I asked yesterday was about the timer1 tick event.
But maybe I can use some other way then a timer to check in real time the sub directories?
The idea here is to check all the time every 100ms in the timer tick event the main directory and all sub directories for gif files.
The rule is first check and find the Israel.gif file display it in pictureBox1 and set the checkbox to true.
Then after that continue and find all sub directories gif files and set the checkboxes near them to true. Don't show the other gifs in the pictureBox1 only the Israel.gif
Why I'm asking this way? Because I wanted to display maybe a progressBar or some other indication too when each gif is downloaded. But the way I'm using the BackgroundWorker and the web client - how can I check when a gif is downloaded completely? I can check and I'm using a progressBar for overall process - but per gif download?
That's why I'm using the timer1.

You may change your approach:
keep the timer,
don't use a backgroundworker,
execute the files download in a secondary thread.
In the secondary thread, store somewhere (in variables of the form) the number of files downloaded and the name of the file currently downloaded + any additional info you want to display.
Use the timer to increment your progressbar, to display the file in progress + other info.
You don't need to browse your directory: all info is set in variables by the secondary thread.

How can I make sure 100% that the backgroundworker is not busy and then start it over again?

I have a button click event where I make once some Lists and start the backgroundworker1:
private void btnDownload_Click(object sender, EventArgs e)
{
btnDownload.Enabled = false;
label7.Text = "Downloading...";
ei.Init();
if (countryList.Count() == 0)
{
foreach (ExtractImages.Continent continent in ei.world.continents)
{
foreach (ExtractImages.Country country in continent.countries)
{
if (country.name == "Israel")
{
foreach (string imageUri in country.imageUrls)
{
countryList.Add(imageUri);
}
}
else
{
foreach (string imageUri in country.imageUrls)
{
newList.Add(imageUri);
}
}
}
}
}
backgroundWorker1.RunWorkerAsync();
}
In the dowork event:
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
if (downloaded == false)
{
getTotalBytes(countryList);
CreateCountryDateTimeDirectories(countryList);
downloadFile(countryList);
}
else
{
getTotalBytes(newList);
CreateCountryDateTimeDirectories(newList);
downloadFile(newList);
}
}
In the dowork event I have two phases first it will make calculations and will download the links in the List countryList.
What I want to do is once it finish to download all the link in countryLinks start backgroundworker1 over again and this time download the links in the List newList.
This is how l'm downloading the links in the List.
private Queue<string> _downloadUrls = new Queue<string>();
private int urlCount = 0; // keep track of how many urls are processed
private async void downloadFile(IEnumerable<string> urls)
{
urlCount = 0;
foreach (var url in urls)
{
_downloadUrls.Enqueue(url);
urlCount++;
}
// urlCount is now set
await DownloadFile();
}
private async Task DownloadFile()
{
if (_downloadUrls.Any())
{
WebClient client = new WebClient();
client.DownloadProgressChanged += ProgressChanged;
client.DownloadFileCompleted += Completed;
var url = _downloadUrls.Dequeue();
sw = Stopwatch.StartNew();
if (url.Contains("true"))
{
await client.DownloadFileTaskAsync(new Uri(url), #"c:\temp\TempSatFiles\" + urlCount + "Infrared.jpg");
//await client.DownloadFileTaskAsync(new Uri(url), countriesMainPath + "\\" + currentDownloadCountry + "\\" + urlCount + "Infrared.jpg");
}
else
{
await client.DownloadFileTaskAsync(new Uri(url), #"c:\temp\TempSatFiles\" + urlCount + "Invisible.jpg");
//await client.DownloadFileTaskAsync(new Uri(url), countriesMainPath + "\\" + currentDownloadCountry + "\\" + urlCount + "Invisible.jpg");
}
return;
}
}
double percentageTotalDownload = 0;
double totalBytesDownloaded = 0;
private void ProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
// Calculate download speed and output it to labelSpeed.
label3.Text = string.Format("{0} kb/s", (e.BytesReceived / 1024d / sw.Elapsed.TotalSeconds).ToString("0.00"));
// Update the progressbar percentage only when the value is not the same.
double bytesInCurrentDownload = (double)e.BytesReceived;
double totalBytesCurrentDownload = double.Parse(e.TotalBytesToReceive.ToString());
double percentageCurrentDownload = bytesInCurrentDownload / totalBytesCurrentDownload * 100;
ProgressBar1.Value = int.Parse(Math.Truncate(percentageCurrentDownload).ToString());//e.ProgressPercentage;
// Show the percentage on our label.
Label4.Text = e.ProgressPercentage.ToString() + "%";
// Update the label with how much data have been downloaded so far and the total size of the file we are currently downloading
label10.Text = string.Format("{0} MB's / {1} MB's",
(e.BytesReceived / 1024d / 1024d).ToString("0.00"),
(e.TotalBytesToReceive / 1024d / 1024d).ToString("0.00"));
//Let's update ProgressBar2
totalBytesDownloaded = e.BytesReceived + bytesFromCompletedFiles;
percentageTotalDownload = totalBytesDownloaded / totalBytesToDownload * 100;
progressBar2.Value = (int)percentageTotalDownload;
label6.Text = progressBar2.Value.ToString() + "%";
}
long bytesFromCompletedFiles = 0;
private async void Completed(object sender, AsyncCompletedEventArgs e)
{
var cnt = System.Threading.Interlocked.Decrement(ref urlCount);
if (cnt > 0)
{
await DownloadFile();
label9.Text = urlCount.ToString();
}
else
{
label7.Text = "Download completed";
downloaded = true;
btnDownload.Enabled = true;
sw.Stop();
}
}
Now it will download the links in countryList.
When it finish download all the files in the List it will get to the else part:
label7.Text = "Download completed";
downloaded = true;
btnDownload.Enabled = true;
sw.Stop();
Here i want to restart the backgroundworker1 and this time in the dowork event it will download the links in the newList.
The problem is how do I know that the backgroundworker1 is not busy ? There might be a situation that it downloaded the all the files and the backgroundworker1 is still busy ?
Or maybe I should start the backgroundworker in the completed event of the backgroundworker ? If it finished all the downloads it will then get to the backgroundworker completed event ? or first it will get to the webclient completed event ?

You can check if the worker is busy or not by using...
if(!backgroundworker1 .IsBusy)
backgroundworker1 .RunWorkerAsync();
No, if you've properly checked when it finishes then the worker will finish on when the downloading completes, it can be busy when it will wait for response and the response doesn't come soon.
Yes, when worker completes it work, it is recommended(from my side) to start it again to perform some other tasks.
Yes whenever it will finish, the completed event will be fired.
the event of webclient is inside the backgroundworker event, webclient completed event will be first. You've to debug your code first to see the sequential flow of your code.

C# Multiple progress bars for multiple file downloads

I am writing a C# application for uploading and downloading file. The download uses WebClient object and its DownloadAsycDownload method. The download works fine for multiple files. It downloads as much files as I want.
My problem is I am not able to show the progress of all file in different progress bars which are dynamically added to the form's flowlayout control.
Here is my code:
public ProgressBar[] bar;
public int countBar=0;
...
bar[countBar] = new ProgressBar();
flowLayoutPanel1.Controls.Add(bar[countBar]);
countBar++;
request.DownloadProgressChanged += new DownloadProgressChangedEventHandler(DownoadInProgress);
request.DownloadFileCompleted += new AsyncCompletedEventHandler(DownloadFileCompleted);
request.DownloadFileAsync(new Uri(this.uri), localPath);
byte[] fileData = request.DownloadData(this.uri);
FileStream file = File.Create(localPath);
file.Write(fileData, 0, fileData.Length);
file.Close();
}
public void DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
flowLayoutPanel1.Controls.Remove(bar[countBar]);
countBar--;
MessageBox.Show("Download Completed");
}
public void DownoadInProgress(object sender, DownloadProgressChangedEventArgs e)
{
bar[countBar].Maximum = total_bytes;
bar[countBar].Value = (int)e.BytesReceived;
}

You're using a count to index into progress bars, but once one is complete - you remove the last one, where you really should remove the one associated with the file.
I suggest, in this case, using a Dictionary<WebClient, ProgressBar> (might not be WebCliet - should be the type of sender in the events).
...
var progBar = new ProgressBar();
progBar.Maximum = 100;
flowLayoutPanel1.Controls.Add(progBar);
request.DownloadProgressChanged += DownoadInProgress;
request.DownloadFileCompleted += DownloadFileCompleted;
request.DownloadFileAsync(new Uri(this.uri), localPath);
dic.Add(request, progBar);
// You shouldn't download the file synchronously as well!
// You're already downloading it asynchronously.
// byte[] fileData = request.DownloadData(this.uri);
// FileStream file = File.Create(localPath);
// file.Write(fileData, 0, fileData.Length);
// file.Close();
Then, you can remove countBar altogether, and have the new methods:
public void DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
// Can remove (WebClient) cast, if dictionary is <object, ProgressBar>
var request = (WebClient)sender;
flowLayoutPanel1.Controls.Remove(dic[request]);
dic.Remove(request);
MessageBox.Show("Download Completed");
}
public void DownoadInProgress(object sender, DownloadProgressChangedEventArgs e)
{
var progBar = dic[(WebClient)sender];
progBar.Value = e.ProgressPercentage;
}

I would use something like this with lambdas, a bit more concise, no need in dictionary:
var webClient = new WebClient();
var pb = new ProgressBar();
pb.Maximum = 100;
flowLayoutPanel1.Controls.Add(pb);
webClient.DownloadProgressChanged += (o, args) =>
{
pb.Value = args.ProgressPercentage;
};
webClient.DownloadFileCompleted += (o, args) =>
{
flowLayoutPanel1.Controls.Remove(pb);
};
webClient.DownloadFileAsync(new Uri(this.uri), localPath);

How do I Async download multiple files using webclient, but one at a time?

It has been surprisingly hard to find a code example of downloading multiple files using the webclient class asynchronous method, but downloading one at a time.
How can I initiate a async download, but wait until the first is finished until the second, etc. Basically a que.
(note I do not want to use the sync method, because of the increased functionality of the async method.)
The below code starts all my downloads at once. (the progress bar is all over the place)
private void downloadFile(string url)
{
WebClient client = new WebClient();
client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(client_DownloadProgressChanged);
client.DownloadFileCompleted += new AsyncCompletedEventHandler(client_DownloadFileCompleted);
// Starts the download
btnGetDownload.Text = "Downloading...";
btnGetDownload.Enabled = false;
progressBar1.Visible = true;
lblFileName.Text = url;
lblFileName.Visible = true;
string FileName = url.Substring(url.LastIndexOf("/") + 1,
(url.Length - url.LastIndexOf("/") - 1));
client.DownloadFileAsync(new Uri(url), "C:\\Test4\\" + FileName);
}
void client_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
}
void client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
double bytesIn = double.Parse(e.BytesReceived.ToString());
double totalBytes = double.Parse(e.TotalBytesToReceive.ToString());
double percentage = bytesIn / totalBytes * 100;
progressBar1.Value = int.Parse(Math.Truncate(percentage).ToString());
}

What I have done is populate a Queue containing all my urls, then I download each item in the queue. When there are no items left, I can then process all the items. I've mocked some code up below. Keep in mind, the code below is for downloading strings and not files. It shouldn't be too difficult to modify the below code.
private Queue<string> _items = new Queue<string>();
private List<string> _results = new List<string>();
private void PopulateItemsQueue()
{
_items.Enqueue("some_url_here");
_items.Enqueue("perhaps_another_here");
_items.Enqueue("and_a_third_item_as_well");
DownloadItem();
}
private void DownloadItem()
{
if (_items.Any())
{
var nextItem = _items.Dequeue();
var webClient = new WebClient();
webClient.DownloadStringCompleted += OnGetDownloadedStringCompleted;
webClient.DownloadStringAsync(new Uri(nextItem));
return;
}
ProcessResults(_results);
}
private void OnGetDownloadedStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
if (e.Error == null && !string.IsNullOrEmpty(e.Result))
{
// do something with e.Result string.
_results.Add(e.Result);
}
DownloadItem();
}
Edit:
I've modified your code to use a Queue. Not entirely sure how you wanted progress to work. I'm sure if you wanted the progress to cater for all downloads, then you could store the item count in the 'PopulateItemsQueue()' method and use that field in the progress changed method.
private Queue<string> _downloadUrls = new Queue<string>();
private void downloadFile(IEnumerable<string> urls)
{
foreach (var url in urls)
{
_downloadUrls.Enqueue(url);
}
// Starts the download
btnGetDownload.Text = "Downloading...";
btnGetDownload.Enabled = false;
progressBar1.Visible = true;
lblFileName.Visible = true;
DownloadFile();
}
private void DownloadFile()
{
if (_downloadUrls.Any())
{
WebClient client = new WebClient();
client.DownloadProgressChanged += client_DownloadProgressChanged;
client.DownloadFileCompleted += client_DownloadFileCompleted;
var url = _downloadUrls.Dequeue();
string FileName = url.Substring(url.LastIndexOf("/") + 1,
(url.Length - url.LastIndexOf("/") - 1));
client.DownloadFileAsync(new Uri(url), "C:\\Test4\\" + FileName);
lblFileName.Text = url;
return;
}
// End of the download
btnGetDownload.Text = "Download Complete";
}
private void client_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
if (e.Error != null)
{
// handle error scenario
throw e.Error;
}
if (e.Cancelled)
{
// handle cancelled scenario
}
DownloadFile();
}
void client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
double bytesIn = double.Parse(e.BytesReceived.ToString());
double totalBytes = double.Parse(e.TotalBytesToReceive.ToString());
double percentage = bytesIn / totalBytes * 100;
progressBar1.Value = int.Parse(Math.Truncate(percentage).ToString());
}

I am struggling to understand where the issue is. If you only call the async method for the first file, won't it only download that file? Why not use the client_downlaodFileCompleted event to initiate the next file download based on some value passed by AsyncCompletedEvents, or maintain a list of downloaded files as a static variable and have client_DownloadFileCompleted iterate tht list to find the next file to download.
Hope that helps but please post more information if I have miunderstood your question.

I would make a new method, for example named getUrlFromQueue which returns me a new url from the queue (collection or array) and deletes it.. then it calls downloadFile(url) - and in client_DownloadFileCompleted I call getUrlFromQueue again.