using System;
using System.ComponentModel;
using System.Threading;
using System.Windows.Forms;
namespace ArdupilotMega.Controls
{
/// <summary>
/// Form that is shown to the user during a background operation
/// </summary>
/// <remarks>
/// Performs operation excplicitely on a threadpool thread due to
/// Mono not playing nice with the BackgroundWorker
/// </remarks>
public partial class ProgressReporterDialogue : Form
{
private Exception workerException;
public ProgressWorkerEventArgs doWorkArgs;
internal int _progress = -1;
internal string _status = "";
public delegate void DoWorkEventHandler(object sender, ProgressWorkerEventArgs e);
// This is the event that will be raised on the BG thread
public event DoWorkEventHandler DoWork;
public ProgressReporterDialogue()
{
InitializeComponent();
doWorkArgs = new ProgressWorkerEventArgs();
this.btnClose.Visible = false;
}
/// <summary>
/// Called at setup - will kick off the background process on a thread pool thread
/// </summary>
public void RunBackgroundOperationAsync()
{
ThreadPool.QueueUserWorkItem(RunBackgroundOperation);
this.ShowDialog();
}
private void RunBackgroundOperation(object o)
{
try
{
Thread.CurrentThread.Name = "ProgressReporterDialogue Background thread";
}
catch { } // ok on windows - fails on mono
// mono fix - ensure the dialog is running
while (this.IsHandleCreated == false)
System.Threading.Thread.Sleep(1);
this.Invoke((MethodInvoker)delegate
{
// if this windows isnt the current active windows, popups inherit the wrong parent.
this.Focus();
Application.DoEvents();
});
try
{
if (this.DoWork != null) this.DoWork(this, doWorkArgs);
}
catch(Exception e)
{
// The background operation thew an exception.
// Examine the work args, if there is an error, then display that and the exception details
// Otherwise display 'Unexpected error' and exception details
timer1.Stop();
ShowDoneWithError(e, doWorkArgs.ErrorMessage);
return;
}
// stop the timer
timer1.Stop();
// run once more to do final message and progressbar
this.Invoke((MethodInvoker)delegate
{
timer1_Tick(null, null);
});
if (doWorkArgs.CancelRequested && doWorkArgs.CancelAcknowledged)
{
ShowDoneCancelled();
return;
}
if (!string.IsNullOrEmpty(doWorkArgs.ErrorMessage))
{
ShowDoneWithError(null, doWorkArgs.ErrorMessage);
return;
}
if (doWorkArgs.CancelRequested)
{
ShowDoneWithError(null, "Operation could not cancel");
return;
}
ShowDone();
}
// Called as a possible last operation of the bg thread that was cancelled
// - Hide progress bar
// - Set label text
private void ShowDoneCancelled()
{
this.Invoke((MethodInvoker)delegate
{
this.progressBar1.Visible = false;
this.lblProgressMessage.Text = "Cancelled";
this.btnClose.Visible = true;
});
}
// Called as a possible last operation of the bg thread
// - Set progress bar to 100%
// - Wait a little bit to allow the Aero progress animatiom to catch up
// - Signal that we can close
private void ShowDone()
{
this.Invoke((MethodInvoker) delegate
{
this.progressBar1.Style = ProgressBarStyle.Continuous;
this.progressBar1.Value = 100;
this.btnCancel.Visible = false;
this.btnClose.Visible = false;
});
Thread.Sleep(1000);
this.BeginInvoke((MethodInvoker) this.Close);
}
// Called as a possible last operation of the bg thread
// There was an exception on the worker event, so:
// - Show the error message supplied by the worker, or a default message
// - Make visible the error icon
// - Make the progress bar invisible to make room for:
// - Add the exception details and stack trace in an expansion panel
// - Change the Cancel button to 'Close', so that the user can look at the exception message a bit
private void ShowDoneWithError(Exception exception, string doWorkArgs)
{
var errMessage = doWorkArgs ?? "There was an unexpected error";
if (this.InvokeRequired)
{
this.Invoke((MethodInvoker) delegate
{
this.Text = "Error";
this.lblProgressMessage.Left = 65;
this.lblProgressMessage.Text = errMessage;
this.imgWarning.Visible = true;
this.progressBar1.Visible = false;
this.btnCancel.Visible = false;
this.btnClose.Visible = true;
this.linkLabel1.Visible = exception != null;
this.workerException = exception;
});
}
}
private void btnCancel_Click(object sender, EventArgs e)
{
// User wants to cancel -
// * Set the text of the Cancel button to 'Close'
// * Set the cancel button to disabled, will enable it and let the user dismiss the dialogue
// when the async operation is complete
// * Set the status text to 'Cancelling...'
// * Set the progress bar to marquee, we don't know how long the worker will take to cancel
// * Signal the worker.
this.btnCancel.Visible = false;
this.lblProgressMessage.Text = "Cancelling...";
this.progressBar1.Style = ProgressBarStyle.Marquee;
doWorkArgs.CancelRequested = true;
}
private void btn_Close_Click(object sender, EventArgs e)
{
// we have already cancelled, and this now a 'close' button
this.Close();
}
/// <summary>
/// Called from the BG thread
/// </summary>
/// <param name="progress">progress in %, -1 means inderteminate</param>
/// <param name="status"></param>
public void UpdateProgressAndStatus(int progress, string status)
{
// we don't let the worker update progress when a cancel has been
// requested, unless the cancel has been acknowleged, so we know that
// this progress update pertains to the cancellation cleanup
if (doWorkArgs.CancelRequested && !doWorkArgs.CancelAcknowledged)
return;
_progress = progress;
_status = status;
}
private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{
var message = this.workerException.Message
+ Environment.NewLine + Environment.NewLine
+ this.workerException.StackTrace;
CustomMessageBox.Show(message,"Exception Details",MessageBoxButtons.OK,MessageBoxIcon.Information);
}
/// <summary>
/// prevent using invokes on main update status call "UpdateProgressAndStatus", as this is slow on mono
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void timer1_Tick(object sender, EventArgs e)
{
// this value is being currupted - not thread safe
int pgv = _progress;
lblProgressMessage.Text = _status;
if (pgv == -1)
{
this.progressBar1.Style = ProgressBarStyle.Marquee;
}
else
{
this.progressBar1.Style = ProgressBarStyle.Continuous;
try
{
this.progressBar1.Value = pgv;
}
catch { } // clean fail. and ignore, chances are we will hit this again in the next 100 ms
}
}
}
public class ProgressWorkerEventArgs : EventArgs
{
public string ErrorMessage;
public volatile bool CancelRequested;
public volatile bool CancelAcknowledged;
}
}