Android - Drawing to a PDF canvas from WebView

Question

I\'ve been having troubles getting PDF printing work on Android. What I\'m trying to do is render some HTML in WebView, then draw the WebView contents on a PDF canvas and fi

Answer 1

Here is where it gets interesting. What about those hard coded values for the canvas ?:-

 PageInfo pageInfo = new PageInfo.Builder(595,842,1).create();

You need the width and height of the WebView CONTENTS, after you loaded your HTML. YES you do, but there is no getContentWidth method (only a view port value), AND the getContentHeight() is inaccurate !

Answer: sub-class WebView:

/*
  Jon Goodwin
*/
package com.example.html2pdf;//your package

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.webkit.WebView;

class CustomWebView extends WebView
{
    public int rawContentWidth   = 0;                         //unneeded
    public int rawContentHeight  = 0;                         //unneeded
    Context    mContext          = null;                      //unneeded

    public CustomWebView(Context context)                     //unused constructor
    {
        super(context);
        mContext = this.getContext();
    }   

    public CustomWebView(Context context, AttributeSet attrs) //inflate constructor
    {
        super(context,attrs);
        mContext = context;
    }

    public int getContentWidth()
    {
        int ret = super.computeHorizontalScrollRange();//working after load of page
        rawContentWidth = ret;
        return ret;
    }

    public int getContentHeight()
    {
        int ret = super.computeVerticalScrollRange(); //working after load of page
        rawContentHeight = ret;
        return ret;
    }

    public void onPageFinished(WebView page, String url)
    {
        //never gets called, don't know why, but getContentHeight & getContentWidth function after load of page
        rawContentWidth  =  ((CustomWebView) page).getContentWidth();
        rawContentHeight =  ((CustomWebView) page).getContentHeight();

        Log.e("CustomWebView:onPageFinished","ContentWidth: " + ((CustomWebView) page).getContentWidth());
        Log.e("CustomWebView:onPageFinished","ContentHeight: " + ((CustomWebView) page).getContentHeight());
    }

//=========
}//class
//=========

In my modified code (in the other answer) change:

private CustomWebView wv;
    wv = (CustomWebView) this.findViewById(R.id.webView1);

    int my_width  = wv.getContentWidth();
    int my_height = wv.getContentHeight();

and change your layout class entry from WebView to com.example.html2pdf.CustomWebView.

then you good to go !