进度条不更新

Question

我有一个 WPF 表单，其中包含一个按钮和一个进度条元素。当我单击该按钮时，它会从另一个类调用一个函数，该函数启动一个后台工作程序，该工作程序负责通过串行端口读取/写入数据到我正在为其编写 Windows 界面的设备。

之前我在使用一个新线程，但我决定尝试一个后台工作人员，但仍然没有运气。

发生的情况是我单击按钮，进度条保持在 0%，直到我的耗时（10 多秒）for 循环完成，然后进度跳到 100%

任何帮助表示赞赏，在此先感谢。下面是我的接口逻辑代码：

private void connectButton_Click(object sender, RoutedEventArgs e) //Connect button clicked
    {
        if (!Global.isConnected)
        {
            device.readValues((string)portsOpen.SelectedValue, connectProgress);

            portsOpen.IsEnabled = false;
            connectButton.Content = "Disconnect";
        }
        else
        {
            device.disconnect();

            portsOpen.IsEnabled = true;
            connectButton.Content = "Connect";
        }
    }

下面是我的附加课程的代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO.Ports;
using System.Windows.Controls;
using System.ComponentModel;

namespace lookoutSecurity
{
    class agentRadioRead
    {
    /*Local Variable Declarations*/
    SerialPort sp;
    BackgroundWorker worker;
    int attempt = 0;

    public string[] populateAvailablePorts() //Returns string array of open ports
    {
        String[] portsAvailable = SerialPort.GetPortNames();
        return portsAvailable;
    }

    public void readValues(string selectedPort, ProgressBar progressBar) //Function that sets up serial port and background worker
    {
        sp = new SerialPort(selectedPort, 9600, Parity.None, 8, StopBits.One);

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

    private void worker_ProgressChanged(object sender, ProgressChangedEventArgs e) //Update user interface with current percentage
    {
        ProgressBar progressBar = e.UserState as ProgressBar;

        App.Current.Dispatcher.Invoke(
            System.Windows.Threading.DispatcherPriority.Send,
                new Action(
                    delegate()
                    { progressBar.Value = e.ProgressPercentage; }));
    }

    private void worker_DoWork(object sender, DoWorkEventArgs e) //Initial starting point for reading data
    {
        startRead((ProgressBar)e.Argument);
    }

    private string sendInitial() //Sends ? and returns init ASUTTON
    {
        string init = "";
        sp.Write("?");

        for (int i = 0; i < 7; i++)
        {
            try
            {
                init += sp.ReadByte().ToString();
            }
            catch
            {
                break;
            }
        }

        return init;
    }

    private void startRead(ProgressBar progressBar) //Initializes data send and receive
    {
        sp.ReadTimeout = 5000;
        sp.Open();

        string init = sendInitial();

        if (init == Global.AGENT_RADIO)
        {
            sp.Write(Global.READ_VALUES, 0, Global.READ_VALUES.Length);

            byte key = (byte)sp.ReadByte();

            if (Global.START_COMMAND == key)
            {
                for (int i = 1; i < 2247; i++)
                {
                    object progressBarObject = new object();
                    progressBarObject = progressBar;
                    int progress = (i / 2246) * 100;
                    worker.ReportProgress(progress, progressBarObject);

                    readData(i, progressBar);
                    sp.Write(Global.GO_AHEAD, 0, Global.GO_AHEAD.Length);

                    sp.DiscardInBuffer();
                    sp.DiscardOutBuffer();
                }
            }
            else
            {
                System.Windows.MessageBox.Show("Connection Failed - Invalid Key: " + key);
                sp.Close();
            }
        }
        else
        {
            sp.Close();

            if (attempt < 3)
            {
                attempt++;
                startRead(progressBar);
            }
            else
            {
                System.Windows.MessageBox.Show("Connection Failed - Not Agent Radio: " + init);
            }
        }
    }

    private void readData(int iteration, ProgressBar progress) //Reads data for current iteration
    {
        byte value = 0;

        try
        {
            value = (byte)sp.ReadByte();
        }
        catch
        {
            sp.Close();
            Global.isConnected = false;

            if (attempt < 3)
            {
                attempt++;
                startRead(progress);
            }
            else
            {
                System.Windows.MessageBox.Show("Read Timeout - Value Number: " + iteration);
                App.Current.Shutdown();
            }
        }

        if (iteration > 0 && iteration < 385) //read schedule
        {
            double pos = (iteration - 1) / 48;

            int i = (int)Math.Floor(pos);
            int j = (iteration - 1) - (i * 48);

            Live.schedule[i, j] = value;
        }

        if (iteration > 384 && iteration < 1285) //read alarm history
        {
            double pos = (iteration - 385) / 9;

            int i = (int)Math.Floor(pos);
            int j = (iteration - 385) - (i * 9);

            Live.alarms[i, j] = value;
        }

        if (iteration > 1284 && iteration < 1345) //read error log
        {
            double pos = (iteration - 1285) / 6;

            int i = (int)Math.Floor(pos);
            int j = (iteration - 1285) - (i * 6);

            Live.errors[i, j] = value;
        }

        if (iteration > 1344 && iteration < 1945) //read voltage history
        {
            double pos = (iteration - 1345) / 6;

            int i = (int)Math.Floor(pos);
            int j = (iteration - 1345) - (i * 6);

            Live.voltage[i, j] = value;
        }

        if (iteration > 1944 && iteration < 1973) //read holidays
        {
            Live.holidays[iteration - 1945] = value;
        }

        if (iteration > 1972 && iteration < 2168) //read message sequences
        {
            double pos = (iteration - 1973) / 15;

            int i = (int)Math.Floor(pos);
            int j = (iteration - 1973) - (i * 15);

            Live.messages[i, j] = value;
        }

        if (iteration > 2167 && iteration < 2196) //read message info
        {
            Live.recordings[iteration - 2168] = value;
        }

        if (iteration > 2195 && iteration < 2246) //read sysval
        {
            Live.sysval[iteration - 2196] = value;
        }

        if (iteration == 2246 && value == Global.FINISH_COMMAND)
        {
            System.Windows.MessageBox.Show("All values from the device have been received.", "Data Received", System.Windows.MessageBoxButton.OK, System.Windows.MessageBoxImage.Information);

            Global.isConnected = true;
        }
    }

    public void disconnect() //Disconnects device
    {
        if (Global.isConnected == true)
        {
            sp.Write(Global.EXIT_PROGRAM, 0, Global.EXIT_PROGRAM.Length);
            Global.isConnected = false;
        }
    }
}
}

Answer 1

你的问题在这里：

int progress = (i / 2246) * 100;

i/2246 将给出一个 int，它将被截断为零（因为 i 从 0 运行到

我之前就已经爱上了它。您需要将 i 转换为浮点数（或双精度数），以便它进行浮点除法而不是整数除法。然后你需要将所有内容都转换回一个 int，因为 progress 是一个 int。

类似：

int progress = (int)((float)i/2246.0) * 100;

Answer 2

这主要是由于以下原因：

int progress = (i / 2246) * 100;

在i>2246 之前，进度始终为0，这就是为什么在最后一次循环迭代中进度等于1*100=100 之前，您会获得0 的进度值

你应该这样做：

int progress = (int)(((double) i / 2246.0) * 100);