Progress Event (original) (raw)

Summary

Document writer progress notification event.

Syntax

C#

Objective-C

C++/CLI

Java

Python

typedef void (^LTDocumentWriterProgressHandler)(NSInteger percentage, BOOL *stop) 

public void addProgressListener(ProgressListener listener) public void removeProgressListener(ProgressListener listener)

public: event EventHandler<DocumentProgressEventArgs^>^ Progress

def Progress(sender,e): # sender: DocumentWriter e: DocumentProgressEventArgs 

Event Data

The event handler receives an argument of type DocumentProgressEventArgs containing data related to this event. The following DocumentProgressEventArgs properties provide information specific to this event.

Example

This example will show how to use the Progress event to create a Windows Forms dialog box with a progress bar and a cancel button.

using Leadtools; using Leadtools.Codecs; using Leadtools.Document.Writer; public void DocumentWriterProgressExample() { // Get the input and output file names to use var inputFileName = Path.Combine(LEAD_VARS.ImagesDir, "test_3.docx"); var outputFileName = Path.Combine(LEAD_VARS.ImagesDir, "test_multipage_DocumentWriter.pdf"); // Show the progress dialog using (var dlg = new MyProgressDialog(inputFileName, outputFileName)) { if (dlg.ShowDialog() == DialogResult.OK) Debug.WriteLine("Done!"); else Debug.WriteLine("User has canceled the operation or an error occurred."); } } // Dialog box to show the private class MyProgressDialog : Form { // Files private string _inputFileName; private string _outputFileName; // The controls on the dialog private Label _descriptionLabel; private ProgressBar _progressBar; private Button _cancelButton; // Has the operation been canceled? private bool _isCancelPending; // Is the dialog working? private bool _isWorking; public MyProgressDialog(string inputFileName, string outputFileName) { InitializeComponent(); _inputFileName = inputFileName; _outputFileName = outputFileName; _isCancelPending = false; _isWorking = true; } protected override void OnLoad(EventArgs e) { // To keep the UI functioning, do the conversion in a separate thread BeginInvoke(new MethodInvoker(DoWork)); base.OnLoad(e); } private void DoWork() { DocumentWriter docWriter; string operation = string.Empty; EventHandler<DocumentProgressEventArgs> progressHandler = (object sender, DocumentProgressEventArgs e) => { // Update the description label progress bar _descriptionLabel.Text = operation; _progressBar.Value = e.Percentage; // Check if the user clicked the Cancel button, if so, abort the operation if (_isCancelPending) e.Cancel = true; Application.DoEvents(); }; // Get the number of pages var codecs = new RasterCodecs(); codecs.Options.RasterizeDocument.Load.Resolution = 300; var pageCount = codecs.GetTotalPages(_inputFileName); // Create the document writer docWriter = new DocumentWriter(); // Create the document operation = "Creating the document..."; // Subscribe to the progress event docWriter.Progress += new EventHandler<DocumentProgressEventArgs>(progressHandler); docWriter.BeginDocument(_outputFileName, DocumentFormat.Pdf); // Add the pages for (var pageNumber = 1; pageNumber <= pageCount && !_isCancelPending; pageNumber++) { // Load the page as SVG var page = new DocumentWriterSvgPage(); page.SvgDocument = codecs.LoadSvg(_inputFileName, pageNumber, null); // Add the page, notice we will not be using image/text feature (the default) operation = string.Format("Adding page {0} of {1}...", pageNumber, pageCount); docWriter.AddPage(page); // Delete the SVG page.SvgDocument.Dispose(); } // Finally finish writing the PDF file on disk operation = "Finishing the document..."; docWriter.EndDocument(); // Remove the progress handler docWriter.Progress -= new EventHandler<DocumentProgressEventArgs>(progressHandler); codecs.Dispose(); // Set the dialog results based on whether the user has canceled the operation if (_isCancelPending) DialogResult = DialogResult.Cancel; else DialogResult = DialogResult.OK; // The dialog can be closed now _isWorking = false; // We are done Close(); } private void _cancelButton_Click(object sender, EventArgs e) { // Set the isCanceled variable to true, this will break from the // progress callback and closes the dialog _isCancelPending = true; } protected override void OnFormClosing(FormClosingEventArgs e) { // Dont allow the form to close while the callback is still working // Instead, cancel the operation if (_isWorking) e.Cancel = true; base.OnFormClosing(e); } private void InitializeComponent() { // Create the controls in this form, a text label, a progress bar and a cancel button SuspendLayout(); // Text label _descriptionLabel = new Label(); _descriptionLabel.Location = new Point(26, 21); _descriptionLabel.Name = "_descriptionLabel"; _descriptionLabel.Size = new Size(367, 23); _descriptionLabel.TabIndex = 0; _descriptionLabel.TextAlign = ContentAlignment.MiddleLeft; _descriptionLabel.Text = "Creating final document..."; // Progress bar _progressBar = new ProgressBar(); _progressBar.Location = new Point(27, 47); _progressBar.Name = "_progressBar"; _progressBar.Size = new Size(364, 23); _progressBar.TabIndex = 1; // Cancel button _cancelButton = new Button(); _cancelButton.DialogResult = DialogResult.Cancel; _cancelButton.Location = new Point(172, 76); _cancelButton.Name = "_cancelButton"; _cancelButton.Size = new Size(75, 23); _cancelButton.TabIndex = 2; _cancelButton.Text = "Cancel"; _cancelButton.UseVisualStyleBackColor = true; _cancelButton.Click += new System.EventHandler(_cancelButton_Click); // Add the controls Controls.Add(_descriptionLabel); Controls.Add(_progressBar); Controls.Add(_cancelButton); // Initialize the dialog AutoScaleDimensions = new SizeF(6F, 13F); AutoScaleMode = AutoScaleMode.Font; CancelButton = _cancelButton; ClientSize = new Size(420, 118); FormBorderStyle = FormBorderStyle.FixedDialog; MaximizeBox = false; MinimizeBox = false; Name = "MyProgressDialog"; ShowInTaskbar = false; StartPosition = FormStartPosition.CenterParent; Text = "DocumentWriter Progress Example"; ResumeLayout(); } } static class LEAD_VARS { public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; }