Backgroundworker ObservableCollection

Question

There is a file search method:

static public void FindLibrarys(String directoriesPath) { ... //Ищет файлы. Каждый найденный файл передаёт в метод. ProgramsList.FormationProgramsList(file); }

This method processes the file and places in its ObservableCollection:

 static public void FormationProgramsList(String file) { ... // NewData возвращает новый экземпляр структуры. _fileList.Add( NewData( fileName + " | x" + bitCapacityProgram + " | " + myFileInfo.DirectoryName + fileVersion + productName, _fileList.Count, bitCapacityProgram == KompasCapacity ) ); }

In the ViewModel, this collection is associated with the model collection:

 public ProjectViewModel() { InitializeComponent(); _model = (ProjectModel)this.Resources["Model"]; backgroundWorker = ((BackgroundWorker)this.FindResource("backgroundWorker")); _model.ProgramsList = ProgramsList.FileList; // Ну и с самим контроллом ResultName.ItemsSource = _model.ProgramsList; }

So I had to do this search by button, but that the interface does not hang. I did it through Application.DoEvent, but this is Windows.Forms. By this I was told to try by other means. I decided to try through BackgroundWorker.

In VM, in the handler of the button I call:

 backgroundWorker.RunWorkerAsync();

And wrote the following code:

 private void backgroundWorker_DoWork(object sender, DoWorkEventArgs e) { foreach (String path in _model.SearchPathsList) { if (_isContinueSearch) { LibraryFinder.FindLibrarys(path); } else break; } }

Everything starts, only at the first found file throws an exception: System.NotSupportedException when adding an item to the _fileList collection in the FormationProgramsList method.

Questions:

Is it possible to make my project architecture work?
Is it not worth changing the architecture?
Are there any more convenient tools that could be used instead of BackgroundWorker?

Changes:

 // Здесь я просто возвращаю кнопку в исходное состояние, т.к. при первом нажатии она меняет параметры и становится кнопкой остановки поиска. private void backgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) { // Возврат параметров поиска в исходное состояние. FindApp.Tag = true; FindApp.Content = "Найти приложения"; }

And there is no ProgressChanged.

Show RunWorkerCompleted and PropgessChanged if there is one
Do you want the files to be added to the list as they are found or all at once?

andreycha 23.7k 3 39 77 · Accepted Answer · 2016-09-08T07:45:28

In this case, add the ProgressChanged event handler and set the WorkerReportsProgress="True" property (the same in xaml, where the 'DoWork` handler was added).

 private void backgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e) { string file = (string)e.UserState; ProgramsList.FormationProgramsList(file); } private void FindLibrarys(String directoriesPath) { //Ищет файлы. Каждый найденный файл передаёт в метод. backgroundWorker.ReportProgress(0, file); }

Also, make the methods non-static, otherwise you won't have access to backgroundWorker or pass the reference to backgroundWorker to the FindLibrarys method.

Many thanks, I will try. I will report on the results. - Sergey

Backgroundworker ObservableCollection

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