WPF에서 안전하게 UI (기본) 스레드에 액세스

WPF에서 안전하게 UI (기본) 스레드에 액세스

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내가보고있는 로그 파일이 다음과 같은 방식으로 업데이트 (새 텍스트로 추가됨) 될 때마다 데이터 그리드를 업데이트하는 애플리케이션이 있습니다.

private void DGAddRow(string name, FunctionType ft)
    {
                ASCIIEncoding ascii = new ASCIIEncoding();

    CommDGDataSource ds = new CommDGDataSource();

    int position = 0;
    string[] data_split = ft.Data.Split(' ');
    foreach (AttributeType at in ft.Types)
    {
        if (at.IsAddress)
        {

            ds.Source = HexString2Ascii(data_split[position]);
            ds.Destination = HexString2Ascii(data_split[position+1]);
            break;
        }
        else
        {
            position += at.Size;
        }
    }
    ds.Protocol = name;
    ds.Number = rowCount;
    ds.Data = ft.Data;
    ds.Time = ft.Time;

    dataGridRows.Add(ds); 

    rowCount++;
    }
    ...
    private void FileSystemWatcher()
    {
        FileSystemWatcher watcher = new FileSystemWatcher(Environment.CurrentDirectory);
        watcher.Filter = syslogPath;
        watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite
            | NotifyFilters.FileName | NotifyFilters.DirectoryName;
        watcher.Changed += new FileSystemEventHandler(watcher_Changed);
        watcher.EnableRaisingEvents = true;
    }

    private void watcher_Changed(object sender, FileSystemEventArgs e)
    {
        if (File.Exists(syslogPath))
        {
            string line = GetLine(syslogPath,currentLine);
            foreach (CommRuleParser crp in crpList)
            {
                FunctionType ft = new FunctionType();
                if (crp.ParseLine(line, out ft))
                {
                    DGAddRow(crp.Protocol, ft);
                }
            }
            currentLine++;
        }
        else
            MessageBox.Show(UIConstant.COMM_SYSLOG_NON_EXIST_WARNING);
    }

FileWatcher에 대한 이벤트가 발생하면 별도의 스레드가 생성되므로 dataGridRows.Add (ds); 새 행을 추가하기 위해 프로그램은 디버그 모드 중에 경고없이 충돌합니다.

Winforms에서는 Invoke 기능을 사용하여 쉽게 해결되었지만 WPF에서 어떻게해야할지 모르겠습니다.

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당신이 사용할 수있는

Dispatcher.Invoke(Delegate, object[])

온 Application의 (또는 UIElement의) 디스패처.

예를 들어 다음과 같이 사용할 수 있습니다.

Application.Current.Dispatcher.Invoke(new Action(() => { /* Your code here */ }));

또는

someControl.Dispatcher.Invoke(new Action(() => { /* Your code here */ }));

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The best way to go about it would be to get a SynchronizationContext from the UI thread and use it. This class abstracts marshalling calls to other threads, and makes testing easier (in contrast to using WPF's Dispatcher directly). For example:

class MyViewModel
{
    private readonly SynchronizationContext _syncContext;

    public MyViewModel()
    {
        // we assume this ctor is called from the UI thread!
        _syncContext = SynchronizationContext.Current;
    }

    // ...

    private void watcher_Changed(object sender, FileSystemEventArgs e)
    {
         _syncContext.Post(o => DGAddRow(crp.Protocol, ft), null);
    }
}

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Use [Dispatcher.Invoke(DispatcherPriority, Delegate)] to change the UI from another thread or from background.

Step 1. Use the following namespaces

using System.Windows;
using System.Threading;
using System.Windows.Threading;

Step 2. Put the following line where you need to update UI

Application.Current.Dispatcher.Invoke(DispatcherPriority.Background, new ThreadStart(delegate
{
    //Update UI here
}));

Syntax

[BrowsableAttribute(false)]
public object Invoke(
  DispatcherPriority priority,
  Delegate method
)

Parameters

priority

Type: System.Windows.Threading.DispatcherPriority

The priority, relative to the other pending operations in the Dispatcher event queue, the specified method is invoked.

method

Type: System.Delegate

A delegate to a method that takes no arguments, which is pushed onto the Dispatcher event queue.

Return Value

Type: System.Object

The return value from the delegate being invoked or null if the delegate has no return value.

Version Information

Available since .NET Framework 3.0

참고URL : https://stackoverflow.com/questions/11625208/accessing-ui-main-thread-safely-in-wpf