I am Lazy Loading a document in a TabViewItem on the RadTabView Control. Here are the steps.
1. My Page opens and I am on my Main Tab.
2. The user has two Bottom Menu Options, one of them is for a view of a Document.
3. The user selects the Document Tab Option, and the I fire an Async operation that Loads a Byte Array that the PDFViewer is bound to. This loads fine. The document successfully loads in the viewer.
4. The user goes back to the Main Tab
5. The user then selects the Document Tab Option again, the Byte Array is already loaded so I do not Load it again in my ViewModel. So, I am not updating the Source Property on the PDFViewer again once it is loaded. I also tried just reloading the document with the same results.
The application just crashes. My guess is the Rendering or Re-Rendering of the Pdf Document between Tab Selections and there is someting
If the document is never loaded, the app does not crash. However, once I load the document in the PDFViewer that exists on a Tab, the Application will crash if the user moves between tabs.
Stack Trace from the Native Crash Reporting from the Application Output Window.
at <unknown> <0xffffffff>at SkiaSharp.SkiaApi:sk_canvas_draw_path <0x000fe>at SkiaSharp.SKCanvas:DrawPath <0x001f2>at Telerik.XamarinForms.SkiaSharp.PdfSkiaPathPainter:Paint <0x00b42>at Telerik.XamarinForms.SkiaSharp.SkiaPainterBase:Paint <0x0010f>at Telerik.XamarinForms.Common.Painters.Painter:TryPaint <0x00176>at Telerik.XamarinForms.Common.Painters.Painter:Paint <0x003a2>at Telerik.XamarinForms.SkiaSharp.SkiaPainter:Canvas_PaintSurface <0x0038c>at SkiaSharp.Views.Forms.SKCanvasView:OnPaintSurface <0x000bc>at SkiaSharp.Views.Forms.SKCanvasView:SkiaSharp.Views.Forms.ISKCanvasViewController.OnPaintSurface <0x00076>at SkiaSharp.Views.Forms.SKCanvasViewRendererBase`2:OnPaintSurface <0x001d5>at SkiaSharp.Views.iOS.SKCanvasView:DrawInSurface <0x0015c>at SkiaSharp.Views.iOS.SKCanvasView:Draw <0x005b3>at <Module>:runtime_invoke_void__this___CGRect <0x003f9>at <unknown> <0xffffffff>at UIKit.UIApplication:UIApplicationMain <0x00211>at UIKit.UIApplication:Main <0x000b2>at UIKit.UIApplication:Main <0x00222>at EMMA.FINSM.iOS.Application:Main <0x00092>at <Module>:runtime_invoke_void_object <0x00178>
Example of my Binding. Very simple Byte Array Binding, and out of the box example from the QSF Code. I also tried using a Stream and it does the same thing.
<Grid> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition/> </Grid.RowDefinitions> <telerikPdfViewer:RadPdfViewerToolbar PdfViewer="{Binding Source={x:Reference PDFView}}"> <telerikPdfViewer:NavigateToPreviousPageToolbarItem/> <telerikPdfViewer:NavigateToNextPageToolbarItem/> <telerikPdfViewer:NavigateToPageToolbarItem/> <telerikPdfViewer:FitToWidthToolbarItem/> <telerikPdfViewer:ToggleLayoutModeToolbarItem/> </telerikPdfViewer:RadPdfViewerToolbar> <telerikPdfViewer:RadPdfViewer x:Name="PDFView" Grid.Row="1" Source="{Binding Document}" /> </Grid>public byte[] Document{ get => _document; set { SetProperty(ref _document, value); }}
Hi
highlight text with each page
app searches db for word occourences
Viewer then highlghts the word eg. Search for contract, app displays grid of contracts
selecting a row displays the selectedcontract
viewer highlights the search words on the visible page.
on phone so apolgies for spelling
regards
graham
After some use I do have these suggestions:
1. When User changes LayoutMode the ZoomLevel property changed event should also be fired. I have a Numeric Textbox to adjust viewer ZoomLevel and would like to see its text update on a LayoutMode change. However when LayoutModeChanged fires the ZoomLevel has not yet changed nor does ZoomLevelChanged later fire.
2. The toolbar item for Fit to Width should be a Toggle in all cases, i.e. toggling between Fit Width and Fit Height (or Fit Page) and should be effective at all times (sometimes has no effect if LayoutMode changed to Single Page).
3. The toolbar item to toggle LayoutMode should honor an assignment of its text property.
4. I'm currently using the change in VisiblePagesCount to determine the document is visible. However a "Loaded" event might be even better.
5. I would like to release the viewer's memory of the document before closing the XAML page. An Unload command would be helpful. For now I just assign Source = null.
Please add a search option to PDF Viewer.
It will be great If you can also add a thumbnail preview option to view all pages in the PDF and a page slider to help navigate user to any page in seconds.