Cleaned and added a base class for view models with background processing tha uses the new ThreadedAction class to do its background processing; added a view binding interface for WinForms that emulates the WPF design
git-svn-id: file:///srv/devel/repo-conversion/nusu@334 d2e56fa2-650e-0410-a79f-9358c0239efd
This commit is contained in:
Markus Ewald
parent
97183d2335
commit
8cc16143de
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@ -28,433 +28,433 @@ using System.Threading.Tasks;
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namespace Nuclex.Support.Threading {
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/// <summary>Executes actions in a threads</summary>
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public abstract class ThreadRunner : IDisposable {
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/// <summary>Executes actions in a threads</summary>
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public abstract class ThreadRunner : IDisposable {
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#region interface IRunner
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#region interface IRunner
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/// <summary>Interface for a background task runner</summary>
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private interface IRunner {
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/// <summary>Interface for a background task runner</summary>
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private interface IRunner {
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/// <summary>Runs the background task</summary>
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void Run();
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/// <summary>Runs the background task</summary>
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void Run();
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/// <summary>The runner's cancellation token source</summary>
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CancellationTokenSource CancellationTokenSource { get; }
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/// <summary>The runner's cancellation token source</summary>
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CancellationTokenSource CancellationTokenSource { get; }
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}
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}
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#endregion // interface IRunner
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#endregion // interface IRunner
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#region struct Runner
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#region struct Runner
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/// <summary>Runs a background task with no parameters</summary>
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private struct Runner : IRunner {
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/// <summary>Runs a background task with no parameters</summary>
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private struct Runner : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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public Runner(Action action) {
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this.action = action;
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}
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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public Runner(Action action) {
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this.action = action;
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action();
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action();
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return null; }
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return null; }
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}
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/// <summary>Action the runner will execute</summary>
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private Action action;
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/// <summary>Action the runner will execute</summary>
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private Action action;
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}
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}
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#endregion // struct Runner
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#endregion // struct Runner
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#region struct CancellableRunner
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#region struct CancellableRunner
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/// <summary>Runs a background task with no parameters</summary>
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private struct CancellableRunner : IRunner {
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/// <summary>Runs a background task with no parameters</summary>
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private struct CancellableRunner : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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public CancellableRunner(CancellableAction action) {
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this.action = action;
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this.cancellationTokenSource = new CancellationTokenSource();
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}
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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public CancellableRunner(CancellableAction action) {
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this.action = action;
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this.cancellationTokenSource = new CancellationTokenSource();
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.cancellationTokenSource.Token);
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.cancellationTokenSource.Token);
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return this.cancellationTokenSource; }
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return this.cancellationTokenSource; }
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}
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/// <summary>The runner's cancellation token source</summary>
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private CancellationTokenSource cancellationTokenSource;
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/// <summary>Action the runner will execute</summary>
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private CancellableAction action;
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/// <summary>The runner's cancellation token source</summary>
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private CancellationTokenSource cancellationTokenSource;
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/// <summary>Action the runner will execute</summary>
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private CancellableAction action;
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}
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}
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#endregion // struct CancellableRunner
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#endregion // struct CancellableRunner
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#region struct Runner<P1>
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#region struct Runner<P1>
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/// <summary>Runs a background task with one parameter</summary>
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private struct Runner<P1> : IRunner {
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/// <summary>Runs a background task with one parameter</summary>
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private struct Runner<P1> : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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/// <param name="parameter1">Parameter that will be passed to the action</param>
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public Runner(Action<P1> action, P1 parameter1) {
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this.action = action;
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this.parameter1 = parameter1;
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}
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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/// <param name="parameter1">Parameter that will be passed to the action</param>
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public Runner(Action<P1> action, P1 parameter1) {
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this.action = action;
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this.parameter1 = parameter1;
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.parameter1);
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.parameter1);
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return null; }
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return null; }
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}
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/// <summary>Action the runner will execute</summary>
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private Action<P1> action;
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/// <summary>Parameter that will be passed to the action</summary>
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private P1 parameter1;
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/// <summary>Action the runner will execute</summary>
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private Action<P1> action;
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/// <summary>Parameter that will be passed to the action</summary>
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private P1 parameter1;
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}
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}
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#endregion // struct Runner<P1>
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#region struct CancellableRunner<P1>
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/// <summary>Runs a background task with one parameter</summary>
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private struct CancellableRunner<P1> : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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/// <param name="parameter1">Parameter that will be passed to the action</param>
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public CancellableRunner(CancellableAction<P1> action, P1 parameter1) {
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this.action = action;
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this.parameter1 = parameter1;
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this.cancellationTokenSource = new CancellationTokenSource();
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.parameter1, this.cancellationTokenSource.Token);
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return this.cancellationTokenSource; }
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}
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/// <summary>The runner's cancellation token source</summary>
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private CancellationTokenSource cancellationTokenSource;
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/// <summary>Action the runner will execute</summary>
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private CancellableAction<P1> action;
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/// <summary>Parameter that will be passed to the action</summary>
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private P1 parameter1;
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}
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#endregion // struct CancellableRunner<P1>
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#region struct Runner<P1, P2>
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/// <summary>Runs a background task with one parameter</summary>
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private struct Runner<P1, P2> : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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/// <param name="parameter1">First parameter that will be passed to the action</param>
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/// <param name="parameter2">Second parameter that will be passed to the action</param>
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public Runner(Action<P1, P2> action, P1 parameter1, P2 parameter2) {
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this.action = action;
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this.parameter1 = parameter1;
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this.parameter2 = parameter2;
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.parameter1, this.parameter2);
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return null; }
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}
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/// <summary>Action the runner will execute</summary>
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private Action<P1, P2> action;
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/// <summary>First parameter that will be passed to the action</summary>
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private P1 parameter1;
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/// <summary>Second parameter that will be passed to the action</summary>
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private P2 parameter2;
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}
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#endregion // struct Runner<P1, P2>
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#region struct CancellableRunner<P1, P2>
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/// <summary>Runs a background task with one parameter</summary>
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private struct CancellableRunner<P1, P2> : IRunner {
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/// <summary>Initializes a new runner</summary>
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/// <param name="action">Action the runner will execute</param>
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/// <param name="parameter1">First parameter that will be passed to the action</param>
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/// <param name="parameter2">Second parameter that will be passed to the action</param>
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public CancellableRunner(CancellableAction<P1, P2> action, P1 parameter1, P2 parameter2) {
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this.action = action;
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this.parameter1 = parameter1;
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this.parameter2 = parameter2;
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this.cancellationTokenSource = new CancellationTokenSource();
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}
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/// <summary>Executes the runner's action</summary>
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public void Run() {
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this.action(this.parameter1, this.parameter2, this.cancellationTokenSource.Token);
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}
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/// <summary>The runner's cancellation token source</summary>
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public CancellationTokenSource CancellationTokenSource {
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get { return this.cancellationTokenSource; }
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}
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/// <summary>The runner's cancellation token source</summary>
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private CancellationTokenSource cancellationTokenSource;
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/// <summary>Action the runner will execute</summary>
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private CancellableAction<P1, P2> action;
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/// <summary>First parameter that will be passed to the action</summary>
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private P1 parameter1;
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/// <summary>Second parameter that will be passed to the action</summary>
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private P2 parameter2;
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}
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#endregion // struct CancellableRunner<P1, P2>
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/// <summary>Initializes a new background processing handler</summary>
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public ThreadRunner() {
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this.executeQueuedRunnersInThreadDelegate = new Action(executeQueuedRunnersInThread);
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this.queuedRunners = new ConcurrentQueue<IRunner>();
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}
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/// <summary>
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/// Immediately cancels all operations and releases the resources used by the instance
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/// </summary>
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public void Dispose() {
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Dispose(timeoutMilliseconds: 2500);
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}
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/// <summary>
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/// Immediately cancels all operations and releases the resources used by the instance
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/// </summary>
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/// <param name="timeoutMilliseconds">
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/// Time to wait for the background tasks before dropping the tasks unfinished
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/// </param>
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public void Dispose(int timeoutMilliseconds) {
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CancelAllBackgroundOperations();
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Task currentTask;
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lock(this) {
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currentTask = this.currentTask;
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}
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if(currentTask != null) {
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if(!currentTask.Wait(timeoutMilliseconds)) {
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Debug.Assert(false, "Task does not support cancellation or did not cancel in time");
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}
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lock(this) {
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this.currentTask = null;
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IsBusy = false;
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}
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}
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}
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/// <summary>Whether the view model is currently busy executing a task</summary>
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public bool IsBusy {
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get { return this.isBusy; }
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private set {
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if(value != this.isBusy) {
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this.isBusy = value;
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BusyChanged();
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}
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}
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}
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/// <summary>Reports an error</summary>
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/// <param name="exception">Error that will be reported</param>
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protected abstract void ReportError(Exception exception);
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/// <summary>Called when the status of the busy flag changes</summary>
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protected abstract void BusyChanged();
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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public void RunInBackground(Action action) {
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this.queuedRunners.Enqueue(new Runner(action));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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public void RunInBackground(CancellableAction action) {
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this.queuedRunners.Enqueue(new CancellableRunner(action));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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/// <param name="parameter1">Parameter that will be passed to the action</param>
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public void RunInBackground<P1>(Action<P1> action, P1 parameter1) {
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this.queuedRunners.Enqueue(new Runner<P1>(action, parameter1));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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/// <param name="parameter1">Parameter that will be passed to the action</param>
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public void RunInBackground<P1>(CancellableAction<P1> action, P1 parameter1) {
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this.queuedRunners.Enqueue(new CancellableRunner<P1>(action, parameter1));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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/// <param name="parameter1">First parameter that will be passed to the action</param>
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/// <param name="parameter2">Second parameter that will be passed to the action</param>
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public void RunInBackground<P1, P2>(Action<P1, P2> action, P1 parameter1, P2 parameter2) {
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this.queuedRunners.Enqueue(new Runner<P1, P2>(action, parameter1, parameter2));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Executes the specified operation in the background</summary>
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/// <param name="action">Action that will be executed in the background</param>
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/// <param name="parameter1">First parameter that will be passed to the action</param>
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/// <param name="parameter2">Second parameter that will be passed to the action</param>
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public void RunInBackground<P1, P2>(
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CancellableAction<P1, P2> action, P1 parameter1, P2 parameter2
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) {
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this.queuedRunners.Enqueue(new CancellableRunner<P1, P2>(action, parameter1, parameter2));
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startBackgroundProcessingIfNecessary();
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}
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/// <summary>Cancels the currently running background operation</summary>
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public void CancelBackgroundOperation() {
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IRunner currentRunner = this.currentRunner;
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if(currentRunner != null) {
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CancellationTokenSource cancellationTokenSource = currentRunner.CancellationTokenSource;
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if(cancellationTokenSource != null) {
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cancellationTokenSource.Cancel();
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}
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}
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}
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/// <summary>Cancels all queued and the currently running background operation</summary>
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public void CancelAllBackgroundOperations() {
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IRunner runner;
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while(this.queuedRunners.TryDequeue(out runner)) {
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CancellationTokenSource cancellationTokenSource = runner.CancellationTokenSource;
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if(cancellationTokenSource != null) {
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cancellationTokenSource.Cancel();
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}
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}
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CancelBackgroundOperation();
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}
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/// <summary>Whether the background operation has been cancelled</summary>
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//[Obsolete("Please use a method accepting a cancellation token instead of using this")]
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public bool IsBackgroundOperationCancelled {
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get {
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IRunner currentRunner = this.currentRunner;
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if(currentRunner != null) {
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return currentRunner.CancellationTokenSource.IsCancellationRequested;
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} else {
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return false;
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}
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}
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}
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/// <summary>Throws an exception if the background operation was cancelled</summary>
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//[Obsolete("Please use a method accepting a cancellation token instead of using this")]
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public void ThrowIfBackgroundOperationCancelled() {
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IRunner currentRunner = this.currentRunner;
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if(currentRunner != null) {
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currentRunner.CancellationTokenSource.Token.ThrowIfCancellationRequested();
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}
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}
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/// <summary>Executes the queued runners in the background</summary>
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private void executeQueuedRunnersInThread() {
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IsBusy = true;
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IRunner runner;
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while(this.queuedRunners.TryDequeue(out runner)) {
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try {
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this.currentRunner = runner;
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runner.Run();
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}
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catch(OperationCanceledException) {
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// Ignore
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}
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catch(Exception exception) {
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this.currentRunner = null; // When the error is reported this should already be null
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ReportError(exception);
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}
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this.currentRunner = null;
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}
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lock(this) {
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this.currentTask = null;
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IsBusy = false;
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}
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}
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/// <summary>Starts the background processing thread, if needed</summary>
|
||||
private void startBackgroundProcessingIfNecessary() {
|
||||
Task currentTask;
|
||||
|
||||
lock(this) {
|
||||
if(this.currentTask == null) {
|
||||
currentTask = new Task(this.executeQueuedRunnersInThreadDelegate);
|
||||
this.currentTask = currentTask;
|
||||
} else {
|
||||
return; // Task is already running
|
||||
}
|
||||
}
|
||||
|
||||
// Start the task outside of the lock statement so that when the thread starts to run,
|
||||
// it is guaranteed to read the currentTask variable as the task we just created.
|
||||
currentTask.Start();
|
||||
}
|
||||
|
||||
/// <summary>Whether the view model is currently busy executing a task</summary>
|
||||
private volatile bool isBusy;
|
||||
/// <summary>Delegate for the executedQueuedRunnersInThread() method</summary>
|
||||
private Action executeQueuedRunnersInThreadDelegate;
|
||||
/// <summary>Queued background operations</summary>
|
||||
private ConcurrentQueue<IRunner> queuedRunners;
|
||||
/// <summary>Runner currently executing in the background</summary>
|
||||
private volatile IRunner currentRunner;
|
||||
/// <summary>Task that is currently executing the runners</summary>
|
||||
private Task currentTask;
|
||||
|
||||
}
|
||||
#endregion // struct Runner<P1>
|
||||
|
||||
#region struct CancellableRunner<P1>
|
||||
|
||||
/// <summary>Runs a background task with one parameter</summary>
|
||||
private struct CancellableRunner<P1> : IRunner {
|
||||
|
||||
/// <summary>Initializes a new runner</summary>
|
||||
/// <param name="action">Action the runner will execute</param>
|
||||
/// <param name="parameter1">Parameter that will be passed to the action</param>
|
||||
public CancellableRunner(CancellableAction<P1> action, P1 parameter1) {
|
||||
this.action = action;
|
||||
this.parameter1 = parameter1;
|
||||
this.cancellationTokenSource = new CancellationTokenSource();
|
||||
}
|
||||
|
||||
/// <summary>Executes the runner's action</summary>
|
||||
public void Run() {
|
||||
this.action(this.parameter1, this.cancellationTokenSource.Token);
|
||||
}
|
||||
|
||||
/// <summary>The runner's cancellation token source</summary>
|
||||
public CancellationTokenSource CancellationTokenSource {
|
||||
get { return this.cancellationTokenSource; }
|
||||
}
|
||||
|
||||
/// <summary>The runner's cancellation token source</summary>
|
||||
private CancellationTokenSource cancellationTokenSource;
|
||||
/// <summary>Action the runner will execute</summary>
|
||||
private CancellableAction<P1> action;
|
||||
/// <summary>Parameter that will be passed to the action</summary>
|
||||
private P1 parameter1;
|
||||
|
||||
}
|
||||
|
||||
#endregion // struct CancellableRunner<P1>
|
||||
|
||||
#region struct Runner<P1, P2>
|
||||
|
||||
/// <summary>Runs a background task with one parameter</summary>
|
||||
private struct Runner<P1, P2> : IRunner {
|
||||
|
||||
/// <summary>Initializes a new runner</summary>
|
||||
/// <param name="action">Action the runner will execute</param>
|
||||
/// <param name="parameter1">First parameter that will be passed to the action</param>
|
||||
/// <param name="parameter2">Second parameter that will be passed to the action</param>
|
||||
public Runner(Action<P1, P2> action, P1 parameter1, P2 parameter2) {
|
||||
this.action = action;
|
||||
this.parameter1 = parameter1;
|
||||
this.parameter2 = parameter2;
|
||||
}
|
||||
|
||||
/// <summary>Executes the runner's action</summary>
|
||||
public void Run() {
|
||||
this.action(this.parameter1, this.parameter2);
|
||||
}
|
||||
|
||||
/// <summary>The runner's cancellation token source</summary>
|
||||
public CancellationTokenSource CancellationTokenSource {
|
||||
get { return null; }
|
||||
}
|
||||
|
||||
/// <summary>Action the runner will execute</summary>
|
||||
private Action<P1, P2> action;
|
||||
/// <summary>First parameter that will be passed to the action</summary>
|
||||
private P1 parameter1;
|
||||
/// <summary>Second parameter that will be passed to the action</summary>
|
||||
private P2 parameter2;
|
||||
|
||||
}
|
||||
|
||||
#endregion // struct Runner<P1, P2>
|
||||
|
||||
#region struct CancellableRunner<P1, P2>
|
||||
|
||||
/// <summary>Runs a background task with one parameter</summary>
|
||||
private struct CancellableRunner<P1, P2> : IRunner {
|
||||
|
||||
/// <summary>Initializes a new runner</summary>
|
||||
/// <param name="action">Action the runner will execute</param>
|
||||
/// <param name="parameter1">First parameter that will be passed to the action</param>
|
||||
/// <param name="parameter2">Second parameter that will be passed to the action</param>
|
||||
public CancellableRunner(CancellableAction<P1, P2> action, P1 parameter1, P2 parameter2) {
|
||||
this.action = action;
|
||||
this.parameter1 = parameter1;
|
||||
this.parameter2 = parameter2;
|
||||
this.cancellationTokenSource = new CancellationTokenSource();
|
||||
}
|
||||
|
||||
/// <summary>Executes the runner's action</summary>
|
||||
public void Run() {
|
||||
this.action(this.parameter1, this.parameter2, this.cancellationTokenSource.Token);
|
||||
}
|
||||
|
||||
/// <summary>The runner's cancellation token source</summary>
|
||||
public CancellationTokenSource CancellationTokenSource {
|
||||
get { return this.cancellationTokenSource; }
|
||||
}
|
||||
|
||||
/// <summary>The runner's cancellation token source</summary>
|
||||
private CancellationTokenSource cancellationTokenSource;
|
||||
/// <summary>Action the runner will execute</summary>
|
||||
private CancellableAction<P1, P2> action;
|
||||
/// <summary>First parameter that will be passed to the action</summary>
|
||||
private P1 parameter1;
|
||||
/// <summary>Second parameter that will be passed to the action</summary>
|
||||
private P2 parameter2;
|
||||
|
||||
}
|
||||
|
||||
#endregion // struct CancellableRunner<P1, P2>
|
||||
|
||||
/// <summary>Initializes a new background processing handler</summary>
|
||||
public ThreadRunner() {
|
||||
this.executeQueuedRunnersInThreadDelegate = new Action(executeQueuedRunnersInThread);
|
||||
this.queuedRunners = new ConcurrentQueue<IRunner>();
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Immediately cancels all operations and releases the resources used by the instance
|
||||
/// </summary>
|
||||
public void Dispose() {
|
||||
Dispose(timeoutMilliseconds: 2500);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Immediately cancels all operations and releases the resources used by the instance
|
||||
/// </summary>
|
||||
/// <param name="timeoutMilliseconds">
|
||||
/// Time to wait for the background tasks before dropping the tasks unfinished
|
||||
/// </param>
|
||||
public void Dispose(int timeoutMilliseconds) {
|
||||
CancelAllBackgroundOperations();
|
||||
|
||||
Task currentTask;
|
||||
lock(this) {
|
||||
currentTask = this.currentTask;
|
||||
}
|
||||
|
||||
if(currentTask != null) {
|
||||
if(!currentTask.Wait(timeoutMilliseconds)) {
|
||||
Debug.Assert(false, "Task does not support cancellation or did not cancel in time");
|
||||
}
|
||||
lock(this) {
|
||||
this.currentTask = null;
|
||||
IsBusy = false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Whether the view model is currently busy executing a task</summary>
|
||||
public bool IsBusy {
|
||||
get { return this.isBusy; }
|
||||
private set {
|
||||
if(value != this.isBusy) {
|
||||
this.isBusy = value;
|
||||
BusyChanged();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Reports an error</summary>
|
||||
/// <param name="exception">Error that will be reported</param>
|
||||
protected abstract void ReportError(Exception exception);
|
||||
|
||||
/// <summary>Called when the status of the busy flag changes</summary>
|
||||
protected abstract void BusyChanged();
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
public void RunInBackground(Action action) {
|
||||
this.queuedRunners.Enqueue(new Runner(action));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
public void RunInBackground(CancellableAction action) {
|
||||
this.queuedRunners.Enqueue(new CancellableRunner(action));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
/// <param name="parameter1">Parameter that will be passed to the action</param>
|
||||
public void RunInBackground<P1>(Action<P1> action, P1 parameter1) {
|
||||
this.queuedRunners.Enqueue(new Runner<P1>(action, parameter1));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
/// <param name="parameter1">Parameter that will be passed to the action</param>
|
||||
public void RunInBackground<P1>(CancellableAction<P1> action, P1 parameter1) {
|
||||
this.queuedRunners.Enqueue(new CancellableRunner<P1>(action, parameter1));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
/// <param name="parameter1">First parameter that will be passed to the action</param>
|
||||
/// <param name="parameter2">Second parameter that will be passed to the action</param>
|
||||
public void RunInBackground<P1, P2>(Action<P1, P2> action, P1 parameter1, P2 parameter2) {
|
||||
this.queuedRunners.Enqueue(new Runner<P1, P2>(action, parameter1, parameter2));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Executes the specified operation in the background</summary>
|
||||
/// <param name="action">Action that will be executed in the background</param>
|
||||
/// <param name="parameter1">First parameter that will be passed to the action</param>
|
||||
/// <param name="parameter2">Second parameter that will be passed to the action</param>
|
||||
public void RunInBackground<P1, P2>(
|
||||
CancellableAction<P1, P2> action, P1 parameter1, P2 parameter2
|
||||
) {
|
||||
this.queuedRunners.Enqueue(new CancellableRunner<P1, P2>(action, parameter1, parameter2));
|
||||
startBackgroundProcessingIfNecessary();
|
||||
}
|
||||
|
||||
/// <summary>Cancels the currently running background operation</summary>
|
||||
public void CancelBackgroundOperation() {
|
||||
IRunner currentRunner = this.currentRunner;
|
||||
if(currentRunner != null) {
|
||||
CancellationTokenSource cancellationTokenSource = currentRunner.CancellationTokenSource;
|
||||
if(cancellationTokenSource != null) {
|
||||
cancellationTokenSource.Cancel();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Cancels all queued and the currently running background operation</summary>
|
||||
public void CancelAllBackgroundOperations() {
|
||||
IRunner runner;
|
||||
while(this.queuedRunners.TryDequeue(out runner)) {
|
||||
CancellationTokenSource cancellationTokenSource = runner.CancellationTokenSource;
|
||||
if(cancellationTokenSource != null) {
|
||||
cancellationTokenSource.Cancel();
|
||||
}
|
||||
}
|
||||
|
||||
CancelBackgroundOperation();
|
||||
}
|
||||
|
||||
/// <summary>Whether the background operation has been cancelled</summary>
|
||||
//[Obsolete("Please use a method accepting a cancellation token instead of using this")]
|
||||
public bool IsBackgroundOperationCancelled {
|
||||
get {
|
||||
IRunner currentRunner = this.currentRunner;
|
||||
if(currentRunner != null) {
|
||||
return currentRunner.CancellationTokenSource.IsCancellationRequested;
|
||||
} else {
|
||||
return false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Throws an exception if the background operation was cancelled</summary>
|
||||
//[Obsolete("Please use a method accepting a cancellation token instead of using this")]
|
||||
public void ThrowIfBackgroundOperationCancelled() {
|
||||
IRunner currentRunner = this.currentRunner;
|
||||
if(currentRunner != null) {
|
||||
currentRunner.CancellationTokenSource.Token.ThrowIfCancellationRequested();
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Executes the queued runners in the background</summary>
|
||||
private void executeQueuedRunnersInThread() {
|
||||
IsBusy = true;
|
||||
|
||||
IRunner runner;
|
||||
while(this.queuedRunners.TryDequeue(out runner)) {
|
||||
try {
|
||||
this.currentRunner = runner;
|
||||
runner.Run();
|
||||
}
|
||||
catch(OperationCanceledException) {
|
||||
// Ignore
|
||||
}
|
||||
catch(Exception exception) {
|
||||
this.currentRunner = null; // When the error is reported this should already be null
|
||||
ReportError(exception);
|
||||
}
|
||||
this.currentRunner = null;
|
||||
}
|
||||
|
||||
lock(this) {
|
||||
this.currentTask = null;
|
||||
IsBusy = false;
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>Starts the background processing thread, if needed</summary>
|
||||
private void startBackgroundProcessingIfNecessary() {
|
||||
Task currentTask;
|
||||
|
||||
lock(this) {
|
||||
if(this.currentTask == null) {
|
||||
currentTask = new Task(this.executeQueuedRunnersInThreadDelegate);
|
||||
this.currentTask = currentTask;
|
||||
} else {
|
||||
return; // Task is already running
|
||||
}
|
||||
}
|
||||
|
||||
// Start the task outside of the lock statement so that when the thread starts to run,
|
||||
// it is guaranteed to read the currentTask variable as the task we just created.
|
||||
currentTask.Start();
|
||||
}
|
||||
|
||||
/// <summary>Whether the view model is currently busy executing a task</summary>
|
||||
private volatile bool isBusy;
|
||||
/// <summary>Delegate for the executedQueuedRunnersInThread() method</summary>
|
||||
private Action executeQueuedRunnersInThreadDelegate;
|
||||
/// <summary>Queued background operations</summary>
|
||||
private ConcurrentQueue<IRunner> queuedRunners;
|
||||
/// <summary>Runner currently executing in the background</summary>
|
||||
private volatile IRunner currentRunner;
|
||||
/// <summary>Task that is currently executing the runners</summary>
|
||||
private Task currentTask;
|
||||
|
||||
}
|
||||
|
||||
} // namespace Nuclex.Support.Threading
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user