await page.render() crashed on web

[vishwajit76]

pdf is successfully opened but when i try to render page, web app is crashed.

Error: Expected a value of type 'int', but got one of type 'Null' at Object.throw_ [as throw] (http://localhost:49752/dart_sdk.js:5063:11) at Object.castError (http://localhost:49752/dart_sdk.js:5022:15) at Object.cast [as as] (http://localhost:49752/dart_sdk.js:5347:17) at Function.as (http://localhost:49752/dart_sdk.js:19820:19) at _render (http://localhost:49752/packages/pdf_render/src/pdf_render_method_channel.dart.lib.js:602:97) at _render.next (<anonymous>) at http://localhost:49752/dart_sdk.js:40537:33 at _RootZone.runUnary (http://localhost:49752/dart_sdk.js:40407:59) at _FutureListener.thenAwait.handleValue (http://localhost:49752/dart_sdk.js:35328:29) at handleValueCallback (http://localhost:49752/dart_sdk.js:35896:49) at Function._propagateToListeners (http://localhost:49752/dart_sdk.js:35934:17) at _Future.new.[_completeWithValue] (http://localhost:49752/dart_sdk.js:35782:23) at async._AsyncCallbackEntry.new.callback (http://localhost:49752/dart_sdk.js:35803:35) at Object._microtaskLoop (http://localhost:49752/dart_sdk.js:40675:13) at _startMicrotaskLoop (http://localhost:49752/dart_sdk.js:40681:13) at http://localhost:49752/dart_sdk.js:36156:9

[vishwajit76]

crashed on pageNumber `

    return PdfPageImageMethodChannel._(
    pageNumber: obj['pageNumber'] as int,
    x: obj['x'] as int,
    y: obj['y'] as int,
    width: retWidth,
    height: retHeight,
    fullWidth: obj['fullWidth'] as double,
    fullHeight: obj['fullHeight'] as double,
    pageWidth: obj['pageWidth'] as double,
    pageHeight: obj['pageHeight'] as double,
    pixels: pixels,
    buffer: ptr);

`

[espresso3389]

Basically, such error causes on PDF open failure. On which platform did you get the error? And, if possible, could you give me the PDF file?

[vishwajit76]

Error is occured in Web platform. certificate (8).pdf

[espresso3389]

I could not reproduce the issue on 1.0.18. Anyway, getPage may throw exception on PDF decoder error. And your code should handle exception correctly.

[espresso3389]

@vishwajit76 Recent updates contains several null-safety changes. Could you please check the latest version?

[syonip]

I'm also getting this, on Flutter Web. Using plugin version 1.3.0.

From what I see there are two problems:

1. If calling page.render() with no params, I get PlatformException(error, Exception: Invalid PDF page rendering rectangle (null x null), null, null) although the docs say If [width], [height], [fullWidth], [fullHeight], and [dpi] are all 0, the page is rendered at 72 dpi.
2. If I do send some values to width, height, fullWidth, fullHeight, I get Expected a value of type 'int', but got one of type 'Null' It seems the reason is indeed this code: https://github.com/espresso3389/flutter_pdf_render/blob/85def54ac2278d6398dd915103e4f01f31f88e8e/lib/src/pdf_render_method_channel.dart#L263 All the values in obj are null. I changed the code to this and it works, but I'm not sure about some of the values:

return PdfPageImageMethodChannel._(
        pageNumber: pageNumber as int,
        x: x as int,
        y: y as int,
        width: retWidth as int,
        height: retHeight as int,
        fullWidth: fullWidth as double,
        fullHeight: fullHeight as double,
        pageWidth: fullWidth as double,
        pageHeight: fullHeight as double,
        pixels: pixels,
        buffer: ptr);

[espresso3389]

Could you try 1.3.1?

[syonip]

Thanks for quick response. I tested 1.3.1

1. Still getting Exception: Invalid PDF page rendering rectangle (null x null) when calling render() with no args.
2. Still getting Expected a value of type 'int', but got one of type 'Null' , but now I see the only null value is pageNumber.

[guidotheelen]

Also encountering the problem in 1.3.1 on web (Chrome): Uncaught (in promise) Error: PlatformException(error, Exception: Invalid PDF page rendering rectangle (null x null), null, null)

pdfDocument = await PdfDocument.openData(bytes); passes. page = await pdfDocument.getPage(pageNumber); passes. img = await page.render(); fails.

Using: pdfjs 2.4.456

[espresso3389]

1.3.4 that fixes the issue is just released.