Progress Bar for unknown process time - winforms

I am developing winform(c#) that start/stop/restart windows services. I want to put a progress bar till the action is completed. I am new to .net programming. Kindly help me on to achieve this.

You cannot show meaningful progress when you don't know how long it takes. You can't know, services take anywhere from 1 to 30 seconds to start. All you can do is show a "I'm not dead, working on it" indicator to the user. ProgressBar supports that, set the Style property to "Marquee".
You'll also need to start the service in a worker thread to avoid your UI from freezing. That's best done with a BackgroundWorker. Make it look similar to this:
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
ServiceProgressBar.Style = ProgressBarStyle.Marquee;
ServiceProgressBar.Visible = false;
}
private void StartButton_Click(object sender, EventArgs e) {
this.StartButton.Enabled = false;
this.ServiceProgressBar.Visible = true;
this.backgroundWorker1.RunWorkerAsync("foo");
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e) {
var ctl = new ServiceController((string)e.Argument);
ctl.Start();
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) {
this.StartButton.Enabled = true;
this.ServiceProgressBar.Visible = false;
if (e.Error != null) {
MessageBox.Show(e.Error.ToString(), "Could not start service");
}
}

You must divide up the start/stop/restart progress in small parts and after the part is finished you set the progress bar.
For an instant update you need to get into the methods you are executing to get feedback about its status.

Do you mean that you want to start/restart/stop more than one service and want the progress bar to indicate "how far you've processed the list of services to be started/restarted/stopped"? You could do something like:
progressBar.Maximum = listOfServicesToStart.Count;
progressBar.Value = 0;
for (int i = 0; i < listOfServicesToStart.Count; i++)
{
// Start service listOfServicesToStart[i]
progressBar.Value = i;
Application.DoEvents();
}
If you are planning to visualize the starting process of a service: I guess you can't do it nicely. What the Services snap-in in Windows seems to do is:
It tries to start/restart/stop the service
It calls ServiceController.WaitForStatus with a 1sec timeout to see whether the service has entered the respective state
Increases the progress bar value by one and goes to 2. until a timeout is detected (you need to find a reasonable number of seconds to wait for the service to enter the desired state)
This seems to be the only way.

Related

Add items to listbox By thread in WPF using C#

I am using the code below, however it is causing my application to hang and I am unsure as to why. Would anyone be able to help me out here?
void put_items() {
listb.Dispatcher.BeginInvoke(new Action(() =>
{
for (int i = 0; i < 9000000; i++)
{
listb.Items.Add(i.ToString());
}
}));
}
private void Button_Click(object sender, RoutedEventArgs e)
{
Thread mythread = new Thread(put_items);
mythread.Start();
}
If you want to update any UI controls this has to be done in the UI thread. By using the Dispatcher you force your application to execute the code within BeginInvoke-block to be executed on the ui thread.
Depending on how time consuming the work for one item in the for loop is, you could process a bunch of items (say 10 or 100) and then update the ui by using the dispatcher. Notice that each call of Dispatcher.BeginInvoke needs some time (maybe 500 ms).
Another way would be using an event aggregator see here. Then your class containing the button click method would register to the event aggregator and in the thread you would just need the instance of the aggregator and call ea.Publish(new YourCustomEvent(yourItemToUpdateUI)).
This approach is really nice if your application is going to be complex.
thank you but I think that code not work in netframwork 3.5 I think that I resolve By this code
public void put_items()
{
for (int i = 0; i < 999999999; i++)
{
this.Dispatcher.Invoke(new Action (() =>
{
listb.Items.Add(i.ToString());
}));
}
}
private void Button_Click(object sender, RoutedEventArgs e)
{
new Thread(put_items).Start();
}

Integration Testing of WPF GUI: How do I identify that current work was finished

I want to run integration UI tests on my WPF application, and I'm not sure how to detect when the current test has finished so that I can proceed to the next one.
Simplifying, suppose I have a button on my window. When the button is clicked I disable it, I modify the model, and I re-enable the button. Once it detects that the model has changed, WPF changes the view on the screen.
Now I want to run a test that simulates clicking the button again and again. To click the button I’ll use automation, as described in this SO question. But how do I know when the work is finished and the display updated, so as to "click" the button again? Do I hook the botton’s IsEnabledChanged, or is there some global indication that the current cycle of processing has finished?
Edit: What was missing in my description is that I want the user to see the interim results on the screen. For example, if the test has 10 phases I want the user to see something like a Step Counter label with values 1 .. 10 appearing on the screen, and not just the number changing immediately from 1 to 10. See my answer below.
how do I know when the work is finished and the display updated, so as to "click" the button again?
According to your description, you said When the button is clicked I disable it, I modify the model, and I re-enable the button.
Therefore, I can only assume that when the model has changed, the Button will be re-enabled. So you could either attach a handler to the model's NotifyPropertyChanged event, or as you suggested, add a handler for the IsEnabledChanged event.
Here is how I managed to get it working. This might be trivial - I'm a novice with GUI. I'm just posting it here in the hope it'll help other novices like me :)
Anyhow, what I used is a two button solutions: Test and Step. Test starts the testing sequence, Step runs each step of the tests. The Step buttons interact with an Integration Tester By Steps helper.
The helper receives an Init with the Number Of Commands as parameter, (currently the helper generates random commands by itself, so it just needs to know how many commands to generate). The helpe provides a Step method to execute the next command, and a Needs More Steps property to indicate whether testing should continue.
The helper derives form INotifyPropertyChanged and has a Counter dependency property that is displayed on the main window.
The states of the Test and Step buttons are controlled by three helper methods: SetButtonsFor_OutsideTesting, SetButtonsFor_InsideTestingOutsideAnyStep and SetButtonsFor_InsideTestingInsideAStep.
First, I verified that everything is working manually, and then I added a timer and automated the process using the Stack Overflow suggestions on how to programmatically click a button in WPF and how to make a WPF Timer Like C# Timer.
Now, here's the Main Window's code:
private void Test_Click(object sender, RoutedEventArgs e)
{
SetButtonsFor_InsideTestingOutsideAnyStep();
RunTheTestBySteps();
}
public readonly IntegrationTesterBySteps _integrationTesterBySteps =
new IntegrationTesterBySteps();
void RunTheTestBySteps()
{
SetButtonsFor_InsideTestingOutsideAnyStep();
IntegrationTesterBySteps.Init(10);
StartTheTimer();
}
private void StartTheTimer()
{
DispatcherTimer = new DispatcherTimer();
DispatcherTimer.Tick += DispatcherTimer_Tick;
DispatcherTimer.Interval = new TimeSpan(0, 0, 1);
DispatcherTimer.Start();
}
private void StopTheTimer()
{
DispatcherTimer.Stop();
DispatcherTimer.Tick -= DispatcherTimer_Tick;
}
private DispatcherTimer DispatcherTimer { get; set; }
private void DispatcherTimer_Tick(object sender, EventArgs e)
{
if (!BtnStep.IsEnabled) return;
ClickTheStepButton();
CommandManager.InvalidateRequerySuggested();
}
private void BtnStep_Click(object sender, RoutedEventArgs e)
{
SetButtonsFor_InsideTestingInsideAStep();
IntegrationTesterBySteps.Step();
if (this.IntegrationTesterBySteps.NeedsMoreSteps)
SetButtonsFor_InsideTestingOutsideAnyStep();
else
{
SetButtonsFor_OutsideTesting();
StopTheTimer();
}
}
private void ClickTheStepButton()
{
var peer = new ButtonAutomationPeer(BtnStep);
var invokeProv = peer.GetPattern(PatternInterface.Invoke)
as IInvokeProvider;
if (invokeProv != null)
invokeProv.Invoke();
}
void SetButtonsFor_InsideTestingInsideAStep()
{
BtnTest.IsEnabled = false;
BtnStep.IsEnabled = false;
}
void SetButtonsFor_InsideTestingOutsideAnyStep()
{
BtnTest.IsEnabled = false;
BtnStep.IsEnabled = true;
}
void SetButtonsFor_OutsideTesting()
{
BtnTest.IsEnabled = true;
BtnStep.IsEnabled = false;
}

How to ensure wcf service client finishs his works in silverlight?

I use wcf service client to submit changes of data for a silverlight project. The correlative codes like this:
public class DispatcherCollection : UpdatableCollection<DocumentDispatcher>
{
public override void SubmitChanges()
{
DocumentServiceClient client = new DocumentServiceClient();
client.NewDocumentCompleted += (s, e) =>
{
// (s as DocumentServiceClient).CloseAsync();
// do something
};
client.UpdateColumnCompleted += (s, e) =>
{
// (s as DocumentServiceClient).CloseAsync();
// do something
};
client.RemoveDocumentCompleted += (s, e) =>
{
// (s as DocumentServiceClient).CloseAsync();
// do something
};
foreach (DocumentDispatcher d in this)
{
if (d.IsNew)
{
// d=>object[] data
client.NewDocumentAsync(data);
d.IsNew=false;
}
else
{
foreach (string propertyName in d.modifiedProperties)
{
client.UpdateColumnAsync(d.ID, GetPropertyValue(propertyName));
}
dd.ClearModifications();
}
}
foreach (DocumentDispatcher dd in removedItems)
{
client.RemoveDocumentAsync(dd.ID);
}
removedItems.Clear();
}
}
Class UpdatableCollection derives from ObserableCollection, and I implemtent logics in class DocumentDispatcher and UpdatableCollection to buffer the changes of data such as new created, property modified and removed. I use SubmitChanges method to submit all changes to server.
Now I am stuck:
1. I am at a loss when to close the client after a bunlde fo async calls. I don't know which callback is the last one.
2. What will happen when a user closes the IE immediately right after clicking the save button (it seems to be done because it runs async but in fact the updating threads are industriously running.)?
You can keep a counter or use an isbusy function to monitor the callbacks from your Async calls - to make sure they all finished.
If the user fires off a request to the WCF service, the WCF service will complete but there will be no call back - as the application will be closed.
I think that there is no wait handle for silverlight asynchornized call brings inconvenience. Here is my experence. I want to check and submit modifications of data which are not expicitly submitted when browser is closing. I have implemented codes in App_Exit like this:
private void Application_Exit(object sender, EventArgs e)
{
Document doc = EDPViewModel.CurrentViewModel.Document;
if (doc != null) new ServiceClient().SubmitChangesAsync(doc);
}
provided that in the SubmitChangesAsync method, not submitted modifications of doc are found out and submitted. Therefore, because of the asynchronized running features, while the service invoking is being sent, the application is yet immediately closed. And that will dispose related resouces of the application, including Service Invoking Tasks. So the codes above work not. I hope so eagerly that somewhere exists a mechanism, which can export a wait handle from silverlight asynchronized call, so that I can update the above codes whith this:
private void Application_Exit(object sender, EventArgs e)
{
Document doc = EDPViewModel.CurrentViewModel.Document;
if (doc != null)
{
Task t = new TaskFactory().StartNew(() => new ServiceClient().SubmitChangesAsync(doc));
t.Wait();
}
}
With wait operation I can really be sure that all modifications are really definitely submitted. So is there any similar pattern that can be used in silverlight?
It's for me a good news, as you put it, that calls could work like the mode "requesting and forgetting". So I needn' to worry too much about data losing during submitting.
To ensure all service calls are sent out before application is closed, I think, counter is a simple and effient idea. I will try to implement it in my project.
Thank you for your help!

MessageBox.Show early in App startup causes app to terminate

As part of my App's startup procedure, it checks data integrity, and if it finds a problem it pops up a message to the user telling them that it might take a while to repair things.
I'm showing the message using MessageBox.Show. Because the data check is done from a worker thread, I'm switching over to the UI thread to make that call, and then setting a ManualResetEvent to tell the worker thread when the user has acknowledged the message.
I kick off the data check/load very early in the app's lifecycle from the constructor in the main Application class, by spinning off a worker thread (using the ThreadPool).
When I run with the debugger, and the message is displayed, the app just waits for input. When I run without the debugger, the app terminates after displaying the dialog for 10 seconds.
That 10 seconds is a big clue - it tells me that the OS thinks the app took too long to initialize (the OS kills apps that take too long to start up).
I think that my MessageBox.Show is blocking the UI thread before the App.RootFrameNavigating has a chance to be invoked.
My questions:
Does my diagnosis sound right?
I'd prefer to kick off my data load early, because it is almost entirely IO, except for this Message Box, and the sooner I can get my Model loaded, the better, but do you normally delay your data load until later in the app lifecycle?
Any other ideas/suggestions? I can't guarantee which page will be the start page, because the app could be resuming to any page. I'm also thinking of having the MessageBox.Show delay itself until the app has initialized, perhaps polling away for a flag set by App.RootFrameNavigating - does that make sense?
I think your problem is a result of kicking off the worker thread in the Application constructor. You should use the appropriate life-cycle event, in this case: PhoneApplicationService.Activated Event
So, the solution I've come up with is to still kick off the data load in a worker-thread from the Application's constructor, but in my PhoneService's class ShowDialog method that I invoke to invoke MessageBox.Show, I check to see if the initial navigation has occurred:
private readonly ManualResetEvent _appInitialized = new ManualResetEvent(false);
public void AppInitialized()
{
_appInitialized.Set();
}
public void ShowDialog(string caption, string text, Action<MessageBoxResult> callback, MessageBoxButton button = MessageBoxButton.OKCancel)
{
_appInitialized.WaitOne();
DispatcherHelper.CheckBeginInvokeOnUI(() =>
{
var result = MessageBox.Show(text, caption, button);
if (callback != null)
{
callback(result);
}
});
}
Then in my Application class:
private bool _firstNavigate = true;
private void RootFrameNavigating(object sender, NavigatingCancelEventArgs e)
{
if (_firstNavigate)
{
_firstNavigate = false;
var navigationService = (NavigationService) sender;
navigationService.Navigated += NavigationServiceNavigated;
}
....
private void NavigationServiceNavigated(object sender, NavigationEventArgs e)
{
var navigationService = (NavigationService)sender;
navigationService.Navigated -= NavigationServiceNavigated;
PhoneServices.Current.AppInitialized();
}
Anyone see any issues with this approach? Anyone come up with a better way?

What is the Alternative to show "Please wait" window in wpf while the call is non threaded

Recently I needed to implement please wait dialog in wpf application. i found below code. it's really good but it always open an window in saprate thread and hold the position. is there any other alter for below code. while my request of code is non threaded.
private void NewWindowThread<T,P>(Func<P, T> constructor, P param) where T : Window
{
Thread thread = new Thread(() =>
{
T w = constructor(param);
w.Show();
w.Closed += (sender, e) => w.Dispatcher.InvokeShutdown();
System.Windows.Threading.Dispatcher.Run();
});
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
}
to call above method use below lines. where loading window is you window which you want to show at dialog (please wait. windows)
string t = "Please Wait…";
NewWindowThread<LoadingWindow, string>(c => new LoadingWindow(c), t);
Blocking the ui thread was never a good idea, but it is increasingly more a bad idea.
Windows will tell the user that your app stopped responding. This may incite them to force your appliccations. If you render progress bars, they will lose the animation effects, and they may render incorrect. In WPF the gui animations will stop.
Use background threads for the heavy processing, and if you need to write data back in the objects used by your main thread, marshall them back to the gui thread. BackgroundWorker can be useful there.
this might help you out.
public partial class Splash : Window
{
private static Splash splash = new Splash();
// To refresh the UI immediately
private delegate void RefreshDelegate();
private static void Refresh(DependencyObject obj)
{
obj.Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.Render,
(RefreshDelegate)delegate { });
}
public Splash()
{
InitializeComponent();
}
public static void BeginDisplay()
{
splash.Show();
}
public static void EndDisplay()
{
splash.Close();
}
public static void Loading(string test)
{
splash.statuslbl.Content = test;
Refresh(splash.statuslbl);
}
}
using above code
Splash.BeginDisplay();
// Setting the status to show the application is still loading data
Splash.Loading("Connecting...");
// Set to sleep to simulate long running process
Thread.Sleep(1500);
Splash.Loading("Retrieving....");
Thread.Sleep(1500);
Splash.Loading("Success....");
Thread.Sleep(1500);
Splash.EndDisplay();

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