I'm using Xamarin Forms with Android, I need to open a PDF from an URL in my WebView. For some reason, sometime the the Webview is blank. I've searched a lot on Internet and I found some solution that give me the same result, sometime the PDF in the PDF is showed without problem, sometime is a blank page. I'm using "https://drive.google.com/viewerng/viewer?embedded=true&url=" with no results, I'm using this solution ( https://acaliaro.wordpress.com/2017/11/30/open-a-pdf-inside-a-webview-in-xamarin-forms-android/ ) that describe exactly my problem but WebView still show me a blank page sometime.
So, why is so hard to open a PDF Url on Android in a WebView? There is some solution to fix this problem? I don't know what can i else do.
Android WebView not support .pdf file from website, infact, if you try to copy an url with .pdf extension in chrome browser, this will download the file and open in an app. So there is no way to show a PDF in an App in a simple way. But there are two solution:
On Google there are a lot solutions that tells you to download the PDF and show in an webview, but in my case I can't download a PDF and show.
You can write an .html page in your Server that can "wrap" the PDF sended with an URL in GET mode and show it in an .html page without problem ( using jsPDF is an example ) or by using this prefix ( http://drive.google.com/viewerng/viewer?embedded=true&url= ) but sometime i give a blank page, so i write my own pdf viewer. In this link ( https://acaliaro.wordpress.com/2017/11/30/open-a-pdf-inside-a-webview-in-xamarin-forms-android/ ) you can find another solution, but for some reason, it still doesn't works. Maybe because I'm on Android 5.0 device.
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I have the webpage created with angular js file. There are pdf files inside the webpage we want to download and show.
when clicking the pdf file, it just show loading and nth happened. Also shouldOverrideUrlLoading method is never called. This method is not deprecated.
We tried to load the url in external browser and open the pdf, it successfully download and open the pdf file.
I would like to know is there any webview setting I missed out?
current webview settings in my implementation is as below . Kindly help. thank you
webView?.settings?.builtInZoomControls = true
webView?.settings?.domStorageEnabled = true
webView?.settings?.allowFileAccess = true
webView?.settings?.allowContentAccess = true
You should try this one might be it work by WebViewClient.
Check out this -- https://stackoverflow.com/a/14201778/18858169
PDF is a file format NOT handled by WebView, it's designed to show web content, not some documents
if you really want to show PDF inside WebView then you should use some web application, which can take a PDF file (or URL pointing on some) and render content of your file in a "web way", thus WebView could print it
for example Google have such web app and you can open PDFs in it using some of below URLs (these may changed)
https://docs.google.com/viewer?url=http://customdomain.com/pdffile.pdf
https://docs.google.com/gview?embedded=true&url=http://customdomain.com/pdffile.pdf
https://drive.google.com/viewerng/viewer?embedded=true&url=http://customdomain.com/pdffile.pdf
note that you are basing on 3rd-party service - your PDF may be online, but 3rd-party companys server-side may be down or changed routing and your hardcoded URL prefix stop working
and if you want to show "real" PDF then use PdfRenderer class, which will give you a set of Bitmaps, which can be shown with ImageView, no WebView needed
We have a file server on which we place PDF documents and then embed links to them in a smart device app. Up until recently, using links to the PDF documents starting with http:// worked fine for Android and iPhone users. All could load the PDF file just fine. Then a few months back (approximately) Android phone users started reporting they would get an error when trying to load any PDF. Yet iPhone users had no issues loading the same PDF document. It was verified that these PDF documents (several) were not corrupted and opened fine when placed on another file server.
I have an iPhone so I can't give you the exact error msg received by Android users but to reproduce it, it was along the lines of... click the link to the PDF, a button appears showing View PDF, click that button and several apps appear to choose the app to open the PDF with, click one (like Adobe Reader, or Google Drive) and an error appears stating the file could not be opened and may be corrupted of the wrong syntax.
Tonight I found the solution.
The url to the PDF on all these documents on our server had been like http://...
but when I changed it to https://... it works fine.
I can't find ANYWHERE any mention of a change by Google that this is now a requirement.
My question...
Can someone explain and/or point me to a reference that explains why https must be used in embedded links to PDF documents? It seems like a pretty big deal to make this a requirement and not tell anyone. My searching the internet has so far not turned up anything.
I have an App in which I want to display PDF files in a webview. I have managed to get the code up and running, but the problem is when I try to run my App, it displays this "no preview available" to me.
I am thinking the problem is with my PDF URL from firebase. Because another PDF URL loads just fine.
Does anyone know what's wrong? And how can I fix this.
Ok I just tried it myself, the problem is that with firebase the PDF gets downloaded rather than display by webview. Try storeing the PDF in the drive an use its url for webview. Hope it works.
I am downloading PDF file in my application and want to allow user to view it. Is it possible that using webview I can display that pdf file downloaded to SD Card or local memory.
As I know there is workaround in which I can provide the link of pdf file to google url which will open pdf in webview. But it lags and is very slow.
Basic answer, no. You can't open a PDF in a webview; so you either need to fire an Intent to open the file (the file can then open in the default installed app on the device); or write your own PDF reader.
Try to use pdf.js.
See http://www.worldwidewhat.net/2011/08/render-pdf-files-with-html5/
I downloaded its source and placed it in sdcard.
Then I use a WebView to load its index.htm.
It did show pdf file on a webView in sdcard in Android 4.0 device but sometime it show white page. I need to reload it and it finally can show.
Unfortunately, I also tested on Android 2.2 and 2.3 devices. They just show white page, nothing.
I know it make use of html5 canvas technology. I have checked on loading http://html5test.com/ on WebView and have tick on canvas element but still can't show pdf. Strange behaviour. Maybe really depends on Android version.
I have an app where I've button on a webpage that is rendered inside a webview.
Now on click of button , a pdf file gets downloaded , and the same would then need to be opened inside the same webview.
attach a download listener to the web view and change the url as follows..
"https://docs.google.com/gview?embedded=true&url=https://www.example.com/xxxxxyyyyyxz.pdf"
example
https://docs.google.com/gview?embedded=true&url=https://www.adobe.com/support/products/enterprise/knowledgecenter/media/c4611_sample_explain.pdf
it's a link used to open pdf without downloading it...
I hope it solves your problem..
I've found that the google viewer seems to work within the android browser for viewing online PDF files. You could build a link to your pdf so that it is displayed in the viewer. I've not tried doing that within a WebView though.
UPDATE
The link is dead, there is an explanation of how to get the functionality to still work at this link.
In case this link also dies, here is the relevant section:
While the page is no longer available as it redirects to Google Docs/Drive, you can still use the Google Docs Viewer. Paste this URL in a new tab:
https://docs.google.com/viewer?url=
and then paste the address of the document you want to view online. Here's an example:
https://docs.google.com/viewer?url=http://research.google.com/archive/bigtable-osdi06.pdf
I do not think that the present android chrome based browser can support pdf. There are discussion about the same in android forums ( ex: link1 link2)
Your best bet to show pdf is to have adobe pdf reader for android installed.(or concisely put, not possible in web view)
I don't think any browser other than Chrome supports rendering PDFs without a plugin or third party tool. It's probably easier to let the user use his own app to open PDFs.
I used the IText PDF library mentioned in this thread
Android : Is there any free PDF library for Android for a sample project. You could try getting using this API to get the PDF page as an image. I am not familiar with every aspect of Itext so it might have better way to do this.