How to use an Intent to open a PDF file by default android app

Question

I have an android app, and wanted to know how to open a PDF file that will be on Firebase in my application. I do not need him to download the file, simply an Intent where I pass the file path (in case the link) and when clicking the button the default android application open and render the file. What I have currently done is a webview that opens the pdf link by google Docs, however is not working anymore And that’s why I wanted the PDF to be opened through the standard cell phone reader. Below the Java code of the button that calls the webview:

public void onClick(View v) {
            //Intent intent = new Intent(PdfList.this, WebViewPDF.class);
            //startActivity(intent);
            String pdf = "AQUI ENTRA O LINK DO PDF NO FIREBASE";
            WebViewPDF.OpenPDF.setPdf(pdf);
            Intent intent = new Intent(PdfList.this, WebViewPDF.class);
            startActivity(intent);
        }

And below the webview code that opens the PDF on the screen within the application

protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    String pdf = OpenPDF.getPdf();

    WebView mWebView = new WebView(WebViewPDF.this);
    mWebView.getSettings().setJavaScriptEnabled(true);
    mWebView.getSettings().setPluginState(WebSettings.PluginState.ON);
    mWebView.loadUrl("https://docs.google.com/gview?embedded=true&url=" + pdf);
    setContentView(mWebView);
}
public abstract static class OpenPDF extends WebViewPDF{
    private static String pdf;

    public static void setPdf(String pdfLink){
        pdf = pdfLink;
    }
    public static String getPdf(){
        return pdf;
    }
}

Answer 1

The problem of trying to create a intent is that there might not be any PDF reader installed on the device. Some companies put readers as standard apps, but this doesn’t always happen.

Already the issue of opening the Google Drive reader by Webview, you probably have faced problems because there is limit of visualization. So a second option would be pdf.js, open-source project mozila’s, which is perhaps the most viable option as it has no use limit. Just download and copy the project to your assets. Take a read on Viewer options to see more options beyond the basics. See below for an example:

String pdf = "http://www.adobe.com/devnet/acrobat/pdfs/pdf_open_parameters.pdf";

webview = (WebView) findViewById(R.id.webview);
WebSettings settings = webview.getSettings();
settings.setJavaScriptEnabled(true);
settings.setAllowFileAccessFromFileURLs(true);
settings.setAllowUniversalAccessFromFileURLs(true);
settings.setBuiltInZoomControls(true);
webview.setWebChromeClient(new WebChromeClient());
webview.loadUrl("file:///android_asset/pdfjs/web/viewer.html?file=" 
    + pdf  + "#zoom=page-width");

I showed that same option in that reply.

I tested and ended up giving a mistake.

To fix, just enter the file viewer.js and comment on the following code:

if (fileOrigin !== viewerOrigin) {
    throw new Error('file origin does not match viewer\'s');
}

OBS.: The minimum version for operation is API Level: 16 Android 4.1 (JELLY_BEAN), because it is necessary to allocate true for the methods setAllowFileAccessFromFileURLs() and setAllowUniversalAccessFromFileURLs(), to allow you to access the contents of a file from the URL and from any source. Internal files I haven’t run any tests yet. As soon as I can do it, I’ll create a compliment here.

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
    settings.setAllowFileAccessFromFileURLs(true);
    settings.setAllowUniversalAccessFromFileURLs(true);
}