WPF ProgressBar Control Dispatch仍然阻止UI线程

Question

我正在使用WPF尝试在后台运行一个更新进度条的线程.我不想阻止UI线程,所以我运行以下代码.但是UI仍然被阻止.看起来很简单,我做错了什么？

       Dispatcher.BeginInvoke(
        (ThreadStart) delegate(){                   
            for(double i = progressBar_ChangeProgress.Minimum;
                i < progressBar_ChangeProgress.Maximum;
                i++)
                {
                    for (int b = 0; b < 100000000; b++) { }
                    progressBar_ChangeProgress.Value = i;
                }
            EnableAllInputControls();
        }, DispatcherPriority.Background);

Answer 1

为什么不在BackgroundWorker这种情况下利用...

        void Go()
        {
            BackgroundWorker worker = new BackgroundWorker();
            worker.WorkerReportsProgress = true;
            worker.ProgressChanged += new ProgressChangedEventHandler(worker_ProgressChanged);
            worker.DoWork += new DoWorkEventHandler(worker_DoWork);
            worker.RunWorkerAsync();
        }

        void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            progressBar_ChangeProgress.Value = e.ProgressPercentage;
        }

        void worker_DoWork(object sender, DoWorkEventArgs e)
        {
            BackgroundWorker worker = sender as BackgroundWorker;
            for (int b = 0; b < 100; b++) 
            {
                Thread.Sleep(100);
                worker.ReportProgress(b);
            }
        }

更新:

如果你想使用Dispatcher; 设置优先级Normal并在后台线程上执行处理,然后在UI线程上调用方法以提供更新.

        void Go()
        {
            ThreadStart start = delegate()
            {
                //this is taking place on the background thread
                for (int i = 0; i < 100; i++)
                {
                    //this is slowing things down; no real relevance
                    Thread.Sleep(100);

                    //this will marshal us back to the UI thread
                    Dispatcher.Invoke(DispatcherPriority.Normal,
                                         new Action<int>(Update), i
                                         );
                }

            };

            new Thread(start).Start();
        }

        void Update(int value)
        {
            //this is taking place on the UI thread
            _progressBar.Value = value;
        }