for embedded PDFs, can PDFJS support both scrolling and jump to a page number at the same time? - pdf.js

Question

This seems like it should be very standard behavior.
I can display a scrollable PDF with:
var container = document.getElementById('viewerContainer');
var pdfViewer = new PDFJS.PDFViewer({
container: container,
});
PDFJS.getDocument(DEFAULT_URL).then(function (pdfDocument) {
pdfViewer.setDocument(pdfDocument);
});
and I can display the PDF page by page with something like:
PDFJS.getDocument(URL_ANNOTATED_PDF_EXAMPLE).then(function getPdfHelloWorld(pdf) {
pdf.getPage(pageNumber).then(function getPageHelloWorld(page) {
var scale = 1.5;
var viewport = page.getViewport(scale);
var canvas = document.getElementById('the-canvas');
var context = canvas.getContext('2d');
canvas.height = viewport.height;
canvas.width = viewport.width;
var renderContext = {
canvasContext: context,
viewport: viewport
};
page.render(renderContext);
});
But can't seem to find any reference in the API to both allow scrolling and jumping to a particular page, besides:
pdfViewer.currentPageNumber = 3;
which doesn't work...

Answer 1

So I found a way to make this work (mixed with a little Angular code, "$scope.$watch...") I now have other problems with font decoding. But here is a solution that might help someone else.
var me = this;
PDFJS.externalLinkTarget = PDFJS.LinkTarget.BLANK;
var container = document.getElementById('capso-court-document__container');
function renderPDF(url, container) {
function renderPage(page) {
var SCALE = 1;
var pdfPageView = new PDFJS.PDFPageView({
container: container,
id: page.pageIndex + 1,
scale: SCALE,
defaultViewport: page.getViewport(SCALE),
textLayerFactory: new PDFJS.DefaultTextLayerFactory(),
annotationLayerFactory: new PDFJS.DefaultAnnotationLayerFactory()
});
pdfPageView.setPdfPage(page);
return pdfPageView.draw();
}
function renderPages(pdfDoc) {
var pageLoadPromises = [];
for (var num = 1; num <= pdfDoc.numPages; num++) {
pageLoadPromises.push(pdfDoc.getPage(num).then(renderPage));
}
return $q.all(pageLoadPromises);
}
PDFJS.disableWorker = true;
return PDFJS.getDocument(url)
.then(renderPages);
}
$scope.$watch(function() {
return {
filingUrl: me.filingUrl,
whenPageSelected: me.whenPageSelected,
};
}, function(newVal, oldVal) {
if (newVal.filingUrl) {
//newVal.filingUrl = URL_EXAMPLE_PDF_ANNOTATED;
//newVal.filingUrl = URL_EXAMPLE_PDF_ANNOTATED_2;
//newVal.filingUrl = URL_EXAMPLE_PDF_MULTI_PAGE;
if (newVal.filingUrl !== oldVal.filingUrl &&
newVal.whenPageSelected &&
newVal.whenPageSelected.page) {
scrollToPage(newVal.whenPageSelected.page);
}
//HACK - create new container for each newly displayed PDF
container.innerHTML = '';
var newContainerForNewPdfSelection = document.createElement('div');
container.appendChild(newContainerForNewPdfSelection);
renderPDF(newVal.filingUrl, newContainerForNewPdfSelection).then(function() {
if (newVal.whenPageSelected &&
newVal.whenPageSelected.page) {
scrollToPage(newVal.whenPageSelected.page);
}
});
}
}, true);
function scrollToPage(pageNumber) {
var pageContainer = document.getElementById('pageContainer' + pageNumber);
if (pageContainer) {
container.scrollTop = pageContainer.offsetTop;
} else {
console.warn('pdf pageContainer doesn\'t exist for index', pageNumber);
}
}