Rendering HTML in a WebView with custom CSS - android

My app is using JSoup to download the HTML of a message board page (let's say in this case it is a page containing the posts of a given thread). I'd like to take this HTML, strip out unwanted items, and apply custom CSS to style it to be 'mobile' in a WebView.
Should I inject the styles into the HTML as I process it (since I will be processing it anyway) or is there a good way to add a CSS file to my app's assets and simply refer to it. I figure the latter would be ideal, but unsure how to go about it.
I see hints in WebView's loadDataWithBaseURL that you can refer to local assets, but not sure how to utilize it.

You could use WebView.loadDataWithBaseURL
htmlData = "<link rel=\"stylesheet\" type=\"text/css\" href=\"style.css\" />" + htmlData;
// lets assume we have /assets/style.css file
webView.loadDataWithBaseURL("file:///android_asset/", htmlData, "text/html", "UTF-8", null);
And only after that WebView will be able to find and use css-files from the assets directory.
ps And, yes, if you load your html-file form the assets folder, you don't need to specify a base url.

I assume that your style-sheet "style.css" is already located in the assets-folder
load the web-page with jsoup:
doc = Jsoup.connect("http://....").get();
remove links to external style-sheets:
// remove links to external style-sheets
doc.head().getElementsByTag("link").remove();
set link to local style-sheet:
// set link to local stylesheet
// <link rel="stylesheet" type="text/css" href="style.css" />
doc.head().appendElement("link").attr("rel", "stylesheet").attr("type", "text/css").attr("href", "style.css");
make string from jsoup-doc/web-page:
String htmldata = doc.outerHtml();
display web-page in webview:
WebView webview = new WebView(this);
setContentView(webview);
webview.loadDataWithBaseURL("file:///android_asset/.", htmlData, "text/html", "UTF-8", null);

here is the solution
Put your html and css in your /assets/ folder, then load the html file like so:
WebView wv = new WebView(this);
wv.loadUrl("file:///android_asset/yourHtml.html");
then in your html you can reference your css in the usual way
<link rel="stylesheet" type="text/css" href="main.css" />

It's as simple as is:
WebView webview = (WebView) findViewById(R.id.webview);
webview.loadUrl("file:///android_asset/some.html");
And your some.html needs to contain something like:
<link rel="stylesheet" type="text/css" href="style.css" />

If you have your CSS in the internal file storage you can use
//Get a reference to your webview
WebView web = (WebView)findViewById(R.id.webby);
// Prepare some html, it is formated with css loaded from the file style.css
String webContent = "<!DOCTYPE html><html><head><meta charset=\"UTF-8\"><link rel=\"stylesheet\" href=\"style.css\"></head>"
+ "<body><div class=\"running\">I am a text rendered with INDIGO</div></body></html>";
//get and format the path pointing to the internal storage
String internalFilePath = "file://" + getFilesDir().getAbsolutePath() + "/";
//load the html with the baseURL, all files relative to the baseURL will be found
web.loadDataWithBaseURL(internalFilePath, webContent, "text/html", "UTF-8", "");

Is it possible to have all the content rendered in-page, in a given div? You could then reset the css based on the id, and work on from there.
Say you give your div id="ocon"
In your css, have a definition like:
#ocon *{background:none;padding:0;etc,etc,}
and you can set values to clear all css from applying to the content.
After that, you can just use
#ocon ul{}
or whatever, further down the stylesheet, to apply new styles to the content.

You can Use Online Css link To set Style over existing content.
For That you have to load data in webview and enable JavaScript Support.
See Below Code:
WebSettings webSettings=web_desc.getSettings();
webSettings.setJavaScriptEnabled(true);
webSettings.setDefaultTextEncodingName("utf-8");
webSettings.setTextZoom(55);
StringBuilder sb = new StringBuilder();
sb.append("<HTML><HEAD><LINK href=\" http://yourStyleshitDomain.com/css/mbl-view-content.css\" type=\"text/css\" rel=\"stylesheet\"/></HEAD><body>");
sb.append(currentHomeContent.getDescription());
sb.append("</body></HTML>");
currentWebView.loadDataWithBaseURL("file:///android_asset/", sb.toString(), "text/html", "utf-8", null);
Here Use StringBuilder to append String for Style.
sb.append("<HTML><HEAD><LINK href=\" http://yourStyleshitDomain.com/css/mbl-view-content.css\" type=\"text/css\" rel=\"stylesheet\"/></HEAD><body>");
sb.append(currentHomeContent.getDescription());

Related

Android webview, loading css live file, add local

Am using android webview tutorial based create application. how to get local file in live android. Coding given below help me.
String htmlData;
htmlData = "<link rel=\"stylesheet\" type=\"text/css\" href=\"Style.css\" />";
//lets assume we have /assets/style.css file
mWebView.loadDataWithBaseURL("file:///android_asset/", htmlData, "text/html", "UTF-8", null);
Try as webView.loadUrl("file:///android_asset/filename.html");
implement css file in html file. So add <link rel="stylesheet" type="text/css" href="Style.css" /> in html head section.

How to render css file from url in to the webview in android

I have css file url-> http:...../test.css.
Now I have html string htmlString=:
<div class=\"detailInfo\">\r\n<table class=\"leftFloat\">\r\n<tbody>\r\n<tr>\r\\r\n<\/tbody>\r\n<\/table>\r\n<\/div>*
Then,
webView=(WebView) findViewById(R.id.webViewDetials);
webView.setBackgroundColor(0x00000000);
webView.getSettings().setJavaScriptEnabled(true);
webView.loadDataWithBaseURL("http://.../css/test.css", attributes, mime, encoding, null);
I don't know to render above url css in below htmlString html string. any idea.
There are lots of example get css from assets folder but i cannot find load css from url.
I have faced such type of problem, May be helpful for you,
webView=(WebView) findViewById(R.id.webView1);
webView.getSettings().setJavaScriptEnabled(true);
StringBuilder sb = new StringBuilder();
sb.append("<HTML><HEAD><LINK href=\"http://test.com/css/test.css\" type=\"text/css\" rel=\"stylesheet\"/></HEAD><body>");
sb.append(attributes.toString());
sb.append("</body></HTML>");
webView.loadDataWithBaseURL(null, sb.toString(), "text/html", "utf-8", null);
Hopefully, it works.
related Links:
and github plugin: https://github.com/NightWhistler/HtmlSpanner
Android WebView renders blank/white, view doesn't update on css changes or HTML changes, animations are choppy
use Jsoup to cut the CSS t
doc = Jsoup.connect(MyTaskParams.base_URL+MyTaskParams.sub_URL).get();
doc.head().getElementsByTag("link").remove();
doc.head().appendElement("link").attr("rel", "stylesheet").attr("type", "text/css").attr("href", "http://www.xyz.cm/pages/myown.css");

Replace images of a HTML document with local Android resources, before loading the page in a WebView

I know that for security reasons HTML standard doesn't allow anymore the loading of a local resource as image in a document.
Anyway I found that I have to copy the html files in the android-asset project folder if I want to load local pages in a WebView.
What if I want to use an hybrid approach?
I would to get a HTML document from an uri, replace the value of the src attribute of a img HTML tag with a local path and then load the code in a WebView.
Having a html document like this:
<hmtl>
<head>
</head>
<body>
<img src="http://URL-SITE/img/x.jpg">
</body>
</hmtl>
How can i replace http://URL-SITE/img with the path of a local image resource
before the page is loaded by a WebView?
I already tried putting the local image in the folder android-asset and changing the src value in file:///android_asset/img/x.jpg but it didn't work.
Ok guys, thanks for the comments.
The problem was that I used the command loadData
String html ="<html> <head></head> "
+" <body> <img src=\"file:///android_asset/img/x.jpg\"> "
+"</body> </html>";
myWebView.loadData(html, "text/html; charset=UTF-8", null);
instead of
myWebView.loadDataWithBaseURL(null, html, "text/html", "UTF-8", null);

Android WebView loadWithBaseURL

I am wondering how do I set the path for WebViews loadWithBaseURL correctly.
What I want to do is, to load html in a webview, that uses resources that are stored on the external storage.
For Example:
<html>
<head>
<style>body{ background-image:url(beach.jpg); }</style>
</head>
<body>
<img src="football.jpg" />
</body>
</html>
Where beach.jpg and ball.jpg are stored directly in the "root" directory of the phones external storage (/sdcard/beach.jpg and /sdcard/ball.jpg)
So I tried to load the content as follows:
String html = "<html> ... example from above ... </html>";
String base = Environment.getExternalStorageDirectory().getAbsolutePath().toString();
webView.loadDataWithBaseURL("file://" + base, html, "text/html", "utf-8", null);
However the path seems to be wrong, because I can't see the image in the webview.
Any suggestions?
Have you enabled file access on the webview?
webView.getSettings().setAllowFileAccess(true);
Additionally, if you are constructing the HTML yourself - you might consider using full paths for the images.
String html = "<html>... <img src=\"file://"+base+"/football.jpg\" />";
Have you give internet permission?
<uses-permission android:name="android.permission.INTERNET" />
These may also help..
Android webview loadDataWithBaseURL how load images from assets?
http://myexperiencewithandroid.blogspot.com/2011/09/android-loaddatawithbaseurl.html
Android v2.2-2.3.5: WebView : loadDataWithBaseURL : will only load page once

WebView, add local .CSS file to an HTML page?

In android I'm using WebView to display a part of a webpage which I fetched from the internet using HttpClient from Apache. To only have the part I want from the html, I use Jsoup.
String htmlString = EntityUtils.toString(entity4); // full html as a string
Document htmlDoc = Jsoup.parse(htmlString); // .. as a Jsoup Document
Elements tables = htmlDoc.getElementsByTag("table"); //important part
Now I can just load tables.toString() in the WebView and it displays. Now I want to link a CSS file which I store inside my assets folder with this page. I know I can have something like
<LINK href="styles/file.css" type="text/css" rel="stylesheet">
In my html, but how do I link it so that it uses the one I've stored locally?
---EDIT---
I've now changed to this:
StringBuilder sb = new StringBuilder();
sb.append("<HTML><HEAD><LINK href=\"file:///android_asset/htmlstyles_default.css\" type=\"text/css\" rel=\"stylesheet\"/></HEAD><body>");
sb.append(tables.toString());
sb.append("</body></HTML>");
return sb.toString();
Somehow I do not get the styles applied to the page. Is it the location path I used that is wrong?
Seva Alekseyev is right, you should store CSS files in assets folder, but referring by file:///android_asset/filename.css URL doesn't working for me.
There is another solution: put CSS in assets folder, do your manipulation with HTML, but refer to CSS by relative path, and load HTML to WebView by loadDataWithBaseURL() method:
webView.loadDataWithBaseURL("file:///android_asset/", htmlString, "text/html", "utf-8", null);
E.g. you have styles.css file, put it to assets folder, create HTML and load it:
StringBuilder sb = new StringBuilder();
sb.append("<HTML><HEAD><LINK href=\"styles.css\" type=\"text/css\" rel=\"stylesheet\"/></HEAD><body>");
sb.append(tables.toString());
sb.append("</body></HTML>");
webView.loadDataWithBaseURL("file:///android_asset/", sb.toString(), "text/html", "utf-8", null);
P.S. I've come to this solution thanks to Peter Knego's answer.
You cannot store arbitrary files in res - just the specific resource types (drawables, layouts, etc.). The CSS should go to the assets folder instead. Then you can refer to it by the following URL: file:///android_asset/MyStyle.css
On a related note, if you're not storing the file in the assets folder and want to use relative paths, Webview on Android sometimes requires dot-slash before relative paths.
<LINK href="./styles/file.css" type="text/css" rel="stylesheet">
See this post

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