Print Multiple Pages From a UWA - c#

I have about 8 records that I want to print in one batch, each on a separate page. However, the UWP sample for this uses over 600 lines of code to accomplish it. It seems to me that it has to be much, much easier than that. I thought all we'd have to do is add each page to the PrintDocument and send the print job. Apparently not. I'm using this:
async void Print()
{
var printDocument = new PrintDocument();
var printDocumentSource = printDocument.DocumentSource;
var printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested += PrintTaskRequested;
var pages = new List<Page>();
foreach (var item in items)
{
(//Set up variables)
var printPage = new PageToPrint() { //Set properties };
printPage.Set_Up(); //Set up fields
pages.Add(printPage);
}
printDocument.SetPreviewPage(1, page);
printDocument.SetPreviewPageCount(pages.Count, PreviewPageCountType.Final);
foreach (var page in pages)
{
printDocument.AddPage(page);
}
printDocument.AddPagesComplete();
await PrintManager.ShowPrintUIAsync();
}
void PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs e)
{
PrintTask printTask = null;
printTask = e.Request.CreatePrintTask("Kimble Print Job", sourceRequested =>
{
printTask.Completed += PrintTask_Completed;
sourceRequested.SetSource(printDocumentSource);
});
}
private async void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested -= PrintTaskRequested;
});
}
However, it won't generate the print preview. It just sits there spinning and spinning, and if I hit "print" it doesn't succeed (PDF can't open, job never gets to a physical printer.)
I was hoping printing would be at least reasonably easy with the PrintDocument, and I still think it looks like it should be. Am I just missing it here, or does it really take 600+ lines of code to dispatch a simple print job?

However, it won't generate the print preview.
This is because the setPreview method printDocument.SetPreviewPage(1, page); must be put in printDocument.GetPreviewPageevent handle. So you should register the event handle firstly. Same with printDocument.AddPages event handle.You messed up the event handle register and callback function all in one.Here I do a little change of your code and I tested it works well.
protected PrintDocument printDocument;
protected IPrintDocumentSource printDocumentSource;
List<Page> pages = new List<Page>();
Page printPage = new PageToPrint();
public MainPage()
{
this.InitializeComponent();
RegisterForPrinting();
}
private async void BtnPrint_Click(object sender, RoutedEventArgs e)
{
await PrintManager.ShowPrintUIAsync();
}
public void RegisterForPrinting()
{
printDocument = new PrintDocument();
printDocumentSource = printDocument.DocumentSource;
pages.Add(printPage);
printDocument.GetPreviewPage += GetPrintPreviewPage;
printDocument.AddPages += AddPrintPages;
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested += PrintTaskRequested;
}
private void AddPrintPages(object sender, AddPagesEventArgs e)
{
foreach (var page in pages)
{
printDocument.AddPage(page);
}
printDocument.AddPagesComplete();
}
private void GetPrintPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDocument.SetPreviewPage(1, printPage);
printDocument.SetPreviewPageCount(pages.Count, PreviewPageCountType.Final);
}
void PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs e)
{
PrintTask printTask = null;
printTask = e.Request.CreatePrintTask("Kimble Print Job", sourceRequested =>
{
printTask.Completed += PrintTask_Completed;
sourceRequested.SetSource(printDocumentSource);
});
}
private async void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested -= PrintTaskRequested;
});
}
Although you may not need all the code of the sample, but I recommend you to follow the official sample structure and build a PrintHelper class.

Related

System.Windows.Forms.WebBrowser wait until page has been fully loaded

I have been trying a lot of different solutions with wait and async. Nothing seems to work. I was not able to find solution that actually fully waits until page has been fully loaded. All codes are waiting some time but not until page has been loaded and I am getting an error on next process.
How I can set for example code into wait mode until Document.GetElementById("quickFind_text_0") element has been found on page?
Here is my code:
private void button7_Click(object sender, EventArgs e)
{
webBrowser1.Navigate("https://company.crm4.dynamics.com/main.aspx?app=d365default&pagetype=entitylist&etn=opportunity");
webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("quickFind_text_0").SetAttribute("value", "Airbus");
webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("quickFind_text_0").InnerText = "Airbus";
//Thread.Sleep(2000);
HtmlElement fbLink = webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("mainContent").Document.GetElementById("quickFind_button_0"); ;
fbLink.InvokeMember("click");
}
P.S. I have to do this "twice" otherwise it is not working:
webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("quickFind_text_0").SetAttribute("value", "Airbus");
webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("quickFind_text_0").InnerText = "Airbus";
In VBA this works:
While .Busy
DoEvents
Wend
While .ReadyState <> 4
DoEvents
Wend
Is it possible to do the same in C#?
EDIT:
My full code below. For some reason async/await does not work.
System.NullReferenceException HResult=0x80004003 Message=Object
reference not set to an instance of an object. Source=v.0.0.01
StackTrace: at v._0._0._01.Browser.<button7_Click>d__7.MoveNext()
in C:\Users\PC\source\repos\v.0.0.01\v.0.0.01\Browser.cs:line 69
Here is my code:
using System;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace v.0._0._01
{
public static class WebBrowserExtensions
{
public static Task<Uri> DocumentCompletedAsync(this WebBrowser wb)
{
var tcs = new TaskCompletionSource<Uri>();
WebBrowserDocumentCompletedEventHandler handler = null;
handler = (_, e) =>
{
wb.DocumentCompleted -= handler;
tcs.TrySetResult(e.Url);
};
wb.DocumentCompleted += handler;
return tcs.Task;
}
}
public partial class Browser : Form
{
public Browser()
{
InitializeComponent();
}
private async void button7_Click(object sender, EventArgs e)
{
webBrowser1.Navigate("https://company.crm4.dynamics.com/main.aspx?app=d365default&pagetype=entitylist&etn=opportunity");
await webBrowser1.DocumentCompletedAsync(); // async magic
HtmlElement fbLink = webBrowser1.Document.GetElementById("shell-container").Document.GetElementById("mainContent").Document.GetElementById("quickFind_button_0"); ;
fbLink.InvokeMember("click");
}
}
}
Also now I have noticed that quickFind_text_0 and quickFind_button_0 always starts with same words but numbers are changing like quickFind_text_1 and quickFind_button_1 or quickFind_text_2 and quickFind_button_2. However by manual clicking everything works with quickFind_text_0 and quickFind_button_0.
Here is an extension method for easy awaiting of the DocumentCompleted event:
public static class WebBrowserExtensions
{
public static Task<Uri> DocumentCompletedAsync(this WebBrowser wb)
{
var tcs = new TaskCompletionSource<Uri>();
WebBrowserDocumentCompletedEventHandler handler = null;
handler = (_, e) =>
{
wb.DocumentCompleted -= handler;
tcs.TrySetResult(e.Url);
};
wb.DocumentCompleted += handler;
return tcs.Task;
}
}
It can be used like this:
private async void button1_Click(object sender, EventArgs e)
{
webBrowser1.Navigate("https://company.crm4.dynamics.com/main.aspx");
await webBrowser1.DocumentCompletedAsync(); // async magic
HtmlElement fbLink = webBrowser1.Document.GetElementById("quickFind_button_0");
fbLink.InvokeMember("click");
}
The lines after the await will run after the page has completed loading.
Update: Here is another extension method for awaiting a specific element to appear in the page:
public static async Task<HtmlElement> WaitForElementAsync(this WebBrowser wb,
string elementId, int timeout = 30000, int interval = 500)
{
var stopwatch = Stopwatch.StartNew();
while (true)
{
try
{
var element = wb.Document.GetElementById(elementId);
if (element != null) return element;
}
catch { }
if (stopwatch.ElapsedMilliseconds > timeout) throw new TimeoutException();
await Task.Delay(interval);
}
}
It can be used for example after invoking a click event that modifies the page using XMLHttpRequest:
someButton.InvokeMember("click");
var mainContentElement = await webBrowser1.WaitForElementAsync("mainContent", 5000);

How can I print a pdf document from Xamarin.Forms UWP?

I have a Xamarin.Forms application that supports only UWP. I cannot find a way to print a pdf document. Whatever I have seen on the web, for some reason doesn't work for me. E.g. I tried
https://www.syncfusion.com/kb/8767/how-to-print-pdf-documents-in-xamarin-forms-platform
It lets me print, but the preview in the print dialog never shows up, and the progress indicator just keeps rotating forever.
I also tried http://zawayasoft.com/2018/03/13/uwp-print-pdf-files-silently-without-print-dialog/
This gives me errors that I cannot fix.
So I wonder if somebody can suggest something else that would actually work. Maybe something newer than what I have tried (I use VS 2017). Printing without the printing dialog would be preferable.
Thank you in advance.
I used a very dirty hack to do that!
What I had to do was to try to print the image version of the pdf (I did the conversion in backend) and then used the following DependencyInjection:
Inside my Print class in UWP project:
class Print : IPrint
{
void IPrint.Print(byte[] content)
{
Print_UWP printing = new Print_UWP();
printing.PrintUWpAsync(content);
}
}
and the class responsible for printing in uwp:
public class Print_UWP
{
PrintManager printmgr = PrintManager.GetForCurrentView();
PrintDocument PrintDoc = null;
PrintDocument printDoc;
PrintTask Task = null;
Windows.UI.Xaml.Controls.Image ViewToPrint = new Windows.UI.Xaml.Controls.Image();
public Print_UWP()
{
printmgr.PrintTaskRequested += Printmgr_PrintTaskRequested;
}
public async void PrintUWpAsync(byte[] imageData)
{
int i = 0;
while (i < 5)
{
try
{
BitmapImage biSource = new BitmapImage();
using (InMemoryRandomAccessStream stream = new InMemoryRandomAccessStream())
{
await stream.WriteAsync(imageData.AsBuffer());
stream.Seek(0);
await biSource.SetSourceAsync(stream);
}
ViewToPrint.Source = biSource;
if (PrintDoc != null)
{
printDoc.GetPreviewPage -= PrintDoc_GetPreviewPage;
printDoc.Paginate -= PrintDoc_Paginate;
printDoc.AddPages -= PrintDoc_AddPages;
}
this.printDoc = new PrintDocument();
try
{
printDoc.GetPreviewPage += PrintDoc_GetPreviewPage;
printDoc.Paginate += PrintDoc_Paginate;
printDoc.AddPages += PrintDoc_AddPages;
bool showprint = await PrintManager.ShowPrintUIAsync();
}
catch (Exception e)
{
Debug.WriteLine(e.ToString());
}
// printmgr = null;
// printDoc = null;
// Task = null;
PrintDoc = null;
GC.Collect();
printmgr.PrintTaskRequested -= Printmgr_PrintTaskRequested;
break;
}
catch (Exception e)
{
i++;
}
}
}
private void Printmgr_PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs args)
{
var deff = args.Request.GetDeferral();
Task = args.Request.CreatePrintTask("Invoice", OnPrintTaskSourceRequested);
deff.Complete();
}
async void OnPrintTaskSourceRequested(PrintTaskSourceRequestedArgs args)
{
var def = args.GetDeferral();
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
args.SetSource(printDoc.DocumentSource);
});
def.Complete();
}
private void PrintDoc_AddPages(object sender, AddPagesEventArgs e)
{
printDoc.AddPage(ViewToPrint);
printDoc.AddPagesComplete();
}
private void PrintDoc_Paginate(object sender, PaginateEventArgs e)
{
PrintTaskOptions opt = Task.Options;
printDoc.SetPreviewPageCount(1, PreviewPageCountType.Final);
}
private void PrintDoc_GetPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDoc.SetPreviewPage(e.PageNumber, ViewToPrint);
}
}
Please note that this is not a perfect solution and sometimes it crashes without actually being able to trace the exception (which is really strange) so I am sure there must be better answers even though it does the job.

Can't access winforms label after await?

I have a long running method which I made async. I made my button click handler async as well, but when I try to access my label in my button click after the long method is done, it tells me it can't can't access it from another thread. Here is the code:
private void Migrate()
{
for (int i = 2; i <= excelData.GetUpperBound(0); i++)
{
var poco = new ExpandoObject() as IDictionary<string, object>;
foreach (var column in distributionColumnExcelHeaderMappings)
{
if (column.ColumnIndex > 0)
{
var value = excelData[i,column.ColumnIndex]?.ToString();
poco.Add(column.DistributionColumnName.Replace(" ", ""), value);
}
}
pocos.Add(poco);
}
migrationRepository.BulkInsert(insertToTable, "Id", pocos);
}
private async void btnMigrate_Click(object sender, EventArgs e)
{
Task task = new Task(()=> Migrate());
task.Start();
lblStatus.Text = "Migrating data....";
await task;
lblStatus.Text = "Migration Complete";
}
When the button is clicked, I see the status Migrating data..... When that is complete, it throws an error on lblStatus.Text = "Migration Complete". I thought after await, it goes back to the UI thread?
I cleared out most of the code and it still throws the same error. This is a VSTO excel add-in. Could that be part of the problem?
private void Migrate()
{
}
private async void btnMigrate(object sender, EventArgs e)
{
Task.Run(()=>Migrate());
lblStatus.Text = "Done"; //still get error here
}
Try and update your code to the following:
Instead of creating your task and then starting it manually, update it to just await on Task.Run:
private async void btnMigrate_Click(object sender, EventArgs e)
{
lblStatus.Text = "Migrating data....";
await Task.Run(()=> Migrate());
lblStatus.Text = "Migration Complete";
}
Edit:
You can use a helper method that will check to see if the label needs to be invoked before updating.
private async void btnMigrate_Click(object sender, EventArgs e)
{
SetLabelText(lblStatus, "Migrating data....");
await Task.Run(()=> Migrate());
SetLabelText(lblStatus, "Migration complete.");
}
private void SetLabelText(Label label, string text)
{
if (label.InvokeRequired)
{
label.BeginInvoke((MethodInvoker) delegate() {label.Text = text;});
}
else
{
label.Text = text;
}
}

How to run different timer inside a timer without pausing the GUI?

I have a class SendCountingInfo() and it will send a message to server every 5 minutes. The code inside this class are:
public void StartSendCountingInfo()
{
DoStartSendCountingInfo(300000);
}
private void DoStartSendCountingInfo(int iMiSecs)
{
_pingTimer = new System.Timers.Timer(iMiSecs);
_pingTimer.Elapsed += new System.Timers.ElapsedEventHandler(pingTimer_Elapsed);
_pingTimer.Start();
}
void pingTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
PingRemoteHost();
}
When I try to call it in the Windows Form class, it didn't work.
But, when I remove the timer and call PingRemoteHost() directly, it works. However, the form didn't load properly. It shows blank screen but the method PingRemoteHost() work.
Here is the code inside the windows form:
private void Layout_Load(object sender, EventArgs e)
{
tSystemChecker = new System.Timers.Timer(1000);
tSystemChecker.Elapsed += new System.Timers.ElapsedEventHandler(tSystemChecker_Elapsed);
tSystemChecker.Start();
this.WindowState = FormWindowState.Maximized;
}
void tSystemChecker_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
UIThreadWork(this, delegate
{
try
{
SuspendLayout();
DoCheckHardwareStatus();
DoCheckLanguage();
SendCountingInfo sci = new SendCountingInfo();
sci.StartSendCountingInfo();
}
catch (Exception exp)
{
System.Diagnostics.Debug.WriteLine(exp.Message);
System.Diagnostics.Debug.WriteLine(exp.Source);
System.Diagnostics.Debug.WriteLine(exp.StackTrace);
}
ResumeLayout(true);
});
}
Do you have any idea what's wrong?
Use a thread and see if the problem persist
using System.Threading;
//Put this where you want to start the first timer
Thread thread = new Thread(dowork =>
{
public void StartSendCountingInfo();
}
If you are updating the GUI use for your controls
guicontrol.BeginInvoke((MethodInvoker)delegate()
{
guicontrol.Text = "aa";
//etc
});

Awesomium offscreen webview never load a page

public class Program
{
static void Main(string[] args)
{
var session = WebCore.CreateWebSession(new WebPreferences { WebSecurity = false });
var browser = WebCore.CreateWebView(1920, 3000, session, WebViewType.Offscreen);
WebCore.ShuttingDown += WebCoreOnShuttingDown;
browser.ConsoleMessage += BrowserOnConsoleMessage;
browser.LoadingFrameComplete += BrowserOnLoadingFrameComplete;
browser.DocumentReady += BrowserOnDocumentReady;
browser.Source = new Uri("http://www.google.ru/");
var error = browser.GetLastError();
Console.ReadKey();
}
private static void BrowserOnConsoleMessage(object sender, ConsoleMessageEventArgs consoleMessageEventArgs)
{
}
private static void WebCoreOnShuttingDown(object sender, CoreShutdownEventArgs coreShutdownEventArgs)
{
}
private static void BrowserOnDocumentReady(object sender, UrlEventArgs urlEventArgs)
{
}
private static void BrowserOnLoadingFrameComplete(object sender, FrameEventArgs frameEventArgs)
{
}
}
It does not work. None of these events ever fired. error is None.
I'm sure I miss something obvious. Does the WebView should be additionally initialized somehow? I searched in Awesomium Wiki but didn't find any additional information.
I made some research and found instruction here
Wait Until the Page Has Finished Loading
while (view->IsLoading())
web_core->Update();
in .Net the WebCore.Update is deprecated and have a description:
In a non-UI environment (or even in a UI application), you can now
create a dedicated Thread for Awesomium and from that thread, use
WebCore.Run to start auto-updating.
so i created this code example:
static void Main(string[] args)
{
Task t = new Task(() =>
{
WebCore.Initialize(new WebConfig(), true);
WebView browser = WebCore.CreateWebView(1024, 768, WebViewType.Offscreen);
browser.DocumentReady += browser_DocumentReady;
browser.Source = new Uri("https://www.google.ru/");
WebCore.Run();
});
t.Start();
Console.ReadLine();
}
static void browser_DocumentReady(object sender, UrlEventArgs e)
{
Console.WriteLine("DocumentReady");
}
You can find more info in WebCore.Run description.
I do this & seem to work well
static void Main(string[] args)
{
var session = WebCore.CreateWebSession(new WebPreferences { WebSecurity = false });
using (WebView webViewBrowser = WebCore.CreateWebView(1024, 768, session, WebViewType.Offscreen))
{
webViewBrowser.ConsoleMessage += webViewBrowser_ConsoleMessage;
webViewBrowser.LoadingFrameComplete += webViewBrowser_LoadingFrameComplete;
webViewBrowser.Source = new Uri("http://www.google.ru/");
if (WebCore.UpdateState == WebCoreUpdateState.NotUpdating) WebCore.Run();
}
}
static void webViewBrowser_ConsoleMessage(object sender, ConsoleMessageEventArgs e)
{
Debug.Print("{0} at {1}: {2} at '{3}'", e.EventName, e.LineNumber, e.Message, e.Source);
}
static void webViewBrowser_LoadingFrameComplete(object sender, FrameEventArgs e)
{
if (!e.IsMainFrame) return;
WebView webViewBrowser = sender as WebView;
Console.WriteLine(String.Format("Page Title: {0}", webViewBrowser.Title));
Console.WriteLine(String.Format("Loaded URL: {0}", webViewBrowser.Source));
BitmapSurface surface = (BitmapSurface)webViewBrowser.Surface;
surface.SaveToPNG("result.png", true);
WebCore.Shutdown();
}

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