WPF用户控件清理

Question

I have an application coded using WPF and UserControl. I have linked a parent window together with the user control tabs which are loaded when the program starts-up.

From there I am able to select a tab which will open the corresponding UserControl. Some UserControls have background workers with threads some are purely used for data capturing and others for data output or generating reports. When each tab is closed using a class created by us called ClossableItems which allows you to select the close button as well as displaying the tab on our MainWindow.

The problem that we are encountering is that when the UserControl is closed none of the resources are released back to the system aka. the background worker and the resources needed to display the UserControl. I have googled ways to force close my UserControl's but to no avail. Things I have tried :

Background worker:
bwDataCollector.WorkerSupportsCancellation = true;
bwDataCollector.CancellationPending;
bwDataCollector.CancelAsync();


User Control:
this.Dispatcher.ShutdownStarted += Dispatcher_ShutdownStarted
private void Dispatcher_ShutdownStarted(object sender, EventArgs e)
        {
        }

So basically what i'm asking for if any knows of a way to close this UserControls called from a method such as onDestroy that will also release the resources?

And is there also a way that I can use this same method to shut down my background Workers?

Answer 1

You need to signal the background worker to stop and the background worker needs to make sure that is takes care of the signal. Signalling can be implemented using various patterns, the simplest being:

Derive all user controls you have from a basic control (or have them implement an interface) that contains a method named CloseControl . In the CloseControl method, set a flag that signals the background worker to stop.

Before closing the window that contains the user controls, call the CloseControl method on each of them.