我是一名TDD新手,成功地使用MVP模式创建了一个漂亮的小样本应用程序。目前解决方案的主要问题是它阻塞了UI线程。因此,我尝试设置Presenter以使用SynchronizationContext.Current,但当我运行测试时,SynchronizationContext.Current为null。
线程之前的Presenter
public class FtpPresenter : IFtpPresenter
{
...
void _view_GetFilesClicked(object sender, EventArgs e)
{
_view.StatusMessage = Messages.Loading;
try
{
var settings = new FtpAuthenticationSettings()
{
Site = _view.FtpSite,
Username = _view.FtpUsername,
Password = _view.FtpPassword
};
var files = _ftpService.GetFiles(settings);
_view.FilesDataSource = files;
_view.StatusMessage = Messages.Done;
}
catch (Exception ex)
{
_view.StatusMessage = ex.Message;
}
}
...
}
线程前测试
[TestMethod]
public void Can_Get_Files()
{
var view = new FakeFtpView();
var presenter = new FtpPresenter(view, new FakeFtpService(), new FakeFileValidator());
view.GetFiles();
Assert.AreEqual(Messages.Done, view.StatusMessage);
}
现在,在我为Presenter添加了SynchronizationContext Threading之后,我尝试在我的Fake View上设置一个AutoResetEvent来获取StatusMessage,但是当我运行测试时,SynchronizationContext.Current为空。我意识到我在新的Presenter中使用的线程模型并不完美,但是这是测试多线程的正确技术吗?为什么SynchronizationContext.Current为空?我应该做些什么呢?
Presenter添加Threading后
public class FtpPresenter : IFtpPresenter
{
...
void _view_GetFilesClicked(object sender, EventArgs e)
{
_view.StatusMessage = Messages.Loading;
try
{
var settings = new FtpAuthenticationSettings()
{
Site = _view.FtpSite,
Username = _view.FtpUsername,
Password = _view.FtpPassword
};
// Wrap the GetFiles in a ThreadStart
var syncContext = SynchronizationContext.Current;
new Thread(new ThreadStart(delegate
{
var files = _ftpService.GetFiles(settings);
syncContext.Send(delegate
{
_view.FilesDataSource = files;
_view.StatusMessage = Messages.Done;
}, null);
})).Start();
}
catch (Exception ex)
{
_view.StatusMessage = ex.Message;
}
}
...
}
多线程测试
[TestMethod]
public void Can_Get_Files()
{
var view = new FakeFtpView();
var presenter = new FtpPresenter(view, new FakeFtpService(), new FakeFileValidator());
view.GetFiles();
view.GetFilesWait.WaitOne();
Assert.AreEqual(Messages.Done, view.StatusMessage);
}
虚假浏览量
public class FakeFtpView : IFtpView
{
...
public AutoResetEvent GetFilesWait = new AutoResetEvent(false);
public event EventHandler GetFilesClicked = delegate { };
public void GetFiles()
{
GetFilesClicked(this, EventArgs.Empty);
}
...
private List<string> _statusHistory = new List<string>();
public List<string> StatusMessageHistory
{
get { return _statusHistory; }
}
public string StatusMessage
{
get
{
return _statusHistory.LastOrDefault();
}
set
{
_statusHistory.Add(value);
if (value != Messages.Loading)
GetFilesWait.Set();
}
}
...
}