Develop Reference

How to apply a javaScript function on MHTML files in android?

I'm new in coding and now I need some help.
I save my webView content with saveWebArchive() method that in kitkat and above this method save webView as mhtml format. Here is my code that I don't have any problem with this part:
File internalStorage = getApplication().getDir("MyArchive",Context.MODE_PRIVATE);
File webUrlPath = new File(internalStorage.getAbsolutePath());
String urlFileName = webUrlPath.toString();
html_path = urlFileName + File.separator + article.Articlehtml.hashCode() +
".mht";
webView.saveWebArchive(html_path);
When I want to load saved files in webView I use Javascript for change font color that for lower of kitkat it works perfectly but for kitkat and above Changes will not apply. Here another part of my code that I have problem with it:
webView.getSettings().setDomStorageEnabled(true);
webView.getSettings().setDatabaseEnabled(true);
webView.getSettings().setJavaScriptEnabled(true);
File file = new File(html_path);
//for Kitkat and above
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
webView.loadUrl("file:///" + file);
}
else {
String rawData = null;
try {
rawData = getStringFromFile(html_url);
}catch (Exception e){
//e.printStackTrace();
}
webView.loadDataWithBaseURL(null, rawData,"application/x-webarchive-xml","UTF-8", null);
}
webView.setWebViewClient(new WebViewClient(){
public void onPageFinished(WebView view, String url){
view.setBackgroundColor(Color.parseColor("#212121"));
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) { webView.evaluateJavascript("document.body.style.setProperty(\"color\", \"white\");", null);
} else {
webView.loadUrl("javascript:document.body.style.setProperty(\"color\", \"white\");");
}
I expect to apply javaScript for saved webView content for kitkat and above, that's mean I can change font color of the mhtml file after loaded it in a WebView.
Thanks for your attention.

You can use webArchiveReader (check it in GitHub) for lower 19 API. For KitKat and above just load file in webView but mht format doesn't support JavaScript.

Finally, I find a solution for my problem. It's use of ColorMatrixColorFilter for invert colors when webView is loaded.

How to download APK file with its extension from a web view?

I created an app with a web view. This web view opens a page with a lot of links to download APKs. The download process goes smoothly, BUT the downloaded apk file doesn't get its original name and extension.
This is my code:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tech_news);
techView = (WebView) findViewById(R.id.tech_webView);
techView.getSettings().setJavaScriptEnabled(true);
techView.loadUrl("http://egy-tech-droid.blogspot.com.eg/2015/08/blog-post.html");
// This will handle downloading. It requires Gingerbread, though
final DownloadManager manager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
// This is where downloaded files will be written, using the package
// name isn't required
// but it's a good way to communicate who owns the directory
final File destinationDir = new File(Environment.getExternalStorageDirectory(), getPackageName());
if (!destinationDir.exists()) {
destinationDir.mkdir(); // Don't forget to make the directory if
// it's not there
}
techView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
techView.setDownloadListener(new DownloadListener() {
public void onDownloadStart(String url, String userAgent, String contentDisposition,
String mimetype, long contentLength) {
Request request = new Request(Uri.parse(url));
request.allowScanningByMediaScanner();
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, contentDisposition);
DownloadManager dm = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
dm.enqueue(request);
Toast.makeText(getApplicationContext(), "downloading",
// To notify the user that the file
// is being downloaded.
Toast.LENGTH_LONG).show();
}
});
return true;
}
});
}
I want the downloaded file to get its original name and extension, so when the user opens the file later from a file explorer the system recognizes that file as an an apk, not just an unknown file.

get Html source of the PAge Loaded in WebView Android

I am trying to get the full Html Source of the WebPage Loaded into the WebView and my Code is Working Fine But It's giving me null for One url( //mobile.twitter.com)
While on Other pages of Twitter(like //mobile.twitter.com/account),it is working fine.
But Give me an Error for the that One URl;
My Code:
twitter_WebView.addJavascriptInterface(new LoadListener(), "HTMLOUT");
twitter_WebView.loadUrl("javascript:window.HTMLOUT.processHTML(document.documentElement.outerHTML); ");
class LoadListener{
#JavascriptInterface
public void processHTML(String html) throws IOException
{
pageHTML = html; // Giving Me Null here ///
})
}

Android Web-View : Inject local Javascript file to Remote Webpage

It has been asked many times before, I browsed through everything, no clear answers yet.
Question simplified: Is it possible to inject local Javascript file (from asset or storage) to remote webpage loaded in an Android Web-View? I know that it is possible to inject such files to local Webpages (Assets HTML) loaded in a Web-View.
Why do I need this to work? : To make browsing experience faster, by avoiding downloading of bigger files such as Js and CSS files every time. I want to avoid Web-View Caching.

There is a way to 'force' the injection of your local Javascript files from local assets (e.g., assets/js/script.js), and to circumvent the 'Not allowed to load local resource : file:///android_assets/js/script.js ...' issue.
It is similar to what described in another thread (Android webview, loading javascript file in assets folder), with additional BASE64 encoding/decoding for representing your Javascript file as a printable string.
I am using an Android 4.4.2, API level 19 Virtual Device.
Here are some code snippets:
[assets/js/script.js]:
'use strict';
function test() {
// ... do something
}
// more Javascript
[MainActivity.java]:
...
WebView myWebView = (WebView) findViewById(R.id.webView);
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
webSettings.setAllowUniversalAccessFromFileURLs(true);
myWebView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
return false;
}
#Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
injectScriptFile(view, "js/script.js"); // see below ...
// test if the script was loaded
view.loadUrl("javascript:setTimeout(test(), 500)");
}
private void injectScriptFile(WebView view, String scriptFile) {
InputStream input;
try {
input = getAssets().open(scriptFile);
byte[] buffer = new byte[input.available()];
input.read(buffer);
input.close();
// String-ify the script byte-array using BASE64 encoding !!!
String encoded = Base64.encodeToString(buffer, Base64.NO_WRAP);
view.loadUrl("javascript:(function() {" +
"var parent = document.getElementsByTagName('head').item(0);" +
"var script = document.createElement('script');" +
"script.type = 'text/javascript';" +
// Tell the browser to BASE64-decode the string into your script !!!
"script.innerHTML = window.atob('" + encoded + "');" +
"parent.appendChild(script)" +
"})()");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
myWebView.loadUrl("http://www.example.com");
...

loadUrl will work only in old version use evaluateJavascript
webview.evaluateJavascript("(function() { document.getElementsByName('username')[0].value='USERNAME';document.getElementsByName('password')[0].value='PASSWORD'; "+
"return { var1: \"variable1\", var2: \"variable2\" }; })();", new ValueCallback<String>() {
#Override
public void onReceiveValue(String s) {
Log.d("LogName", s); // Prints: {"var1":"variable1","var2":"variable2"}
}
});

Yes, you could use shouldInterceptRequest() to intercept remote url loading and return local stored content.
WebView webview = (WebView) findViewById(R.id.webview);
webview.setWebViewClient(new WebViewClient() {
#Override
public WebResourceResponse shouldInterceptRequest (final WebView view, String url) {
if (url.equals("script_url_to_load_local")) {
return new WebResourceResponse("text/javascript", "UTF-8", new FileInputStream("local_url")));
} else {
return super.shouldInterceptRequest(view, url);
}
}
});

Be careful using evaluateJavascript: if there is a syntax error or exception thrown in your javascript it will call your onReceiveValue with a null. The most common way to support both SDK 19 as well as lower seems to be like this:Fill form in WebView with Javascript
Also if you get terribly desperate for some kind of browser functionality (in my case, never could figure out how to get DRM to work well) you could use a bookmarklet within normal chrome, which works only if you type the bookmark name into the omnibox but does work and does inject javascript.
Also be aware that with the default WebView you can't use javascript alerts to test anything, they don't show. Also be aware that "video" by default (like html <video> tags) doesn't "really work" by default and also DRM video doesn't work by default, they're all configure options :\

Javascript is not working in webView when Loaded from asset folder but working from both http server & localhost

I am trying to load offline version of python documentation into an webview from assetfolder. The offline docs work perfectly in my pc web browser in offline but not working properly in webview (something like jquery is missing).
#SuppressLint("SetJavaScriptEnabled")
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
WebView webView = (WebView) findViewById(R.id.wrapper);
webView.getSettings().setJavaScriptEnabled(true);
webView.setWebChromeClient(new WebChromeClient());
webView.loadUrl("file:///android_asset/python/index.html");
}
}
And this error message is shown when I tried to load the home page or navigate to any page.
09-24 01:03:02.789: E/Web Console(479): ReferenceError: Can't find variable: $ at file:///android_asset/python/index.html:164
And the above error is for a Jquery code snippet ( I think this for that the jquery library isn't loading)
<script type="text/javascript">$('#searchbox').show(0);</script>
But when I load those pages from my local server localhost or http server, this is working perfectly. What did I miss?
Edit
Showing nothing in the webView. After using loadDataWithBaseURL:
#SuppressLint("SetJavaScriptEnabled")
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
WebView webView = (WebView) findViewById(R.id.wrapper);
webView.getSettings().setJavaScriptEnabled(true);
webView.setWebChromeClient(new WebChromeClient());
AssetManager assetManager = getAssets();
String htmlPage = null;
InputStream input;
try {
input = assetManager.open("python/index.html");
int size = input.available();
byte[] buffer = new byte[size];
input.read(buffer);
input.close();
// byte buffer into a string
htmlPage = new String(buffer);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
webView.loadDataWithBaseURL("file:///android_asset/", htmlPage, "text/html", "utf-8", "");
}
}

Your html page should be having reference to
<script type="text/javascript" src="http://code.jquery.com/jquery-1.6.4.min.js">
</script>
Since you say the docs should load offline the jquery js is not being loaded. You could probably bundle jquery along with your application and reference it locally like this
<script src="file:///android_asset/js/jquery-1.8.2.min.js"></script>
Also include
<script src="file:///android_asset/js/jquery.mobile-1.3.2.min.js"></script>
You might also have to load your html page using loadDataWithBaseURL as seen below instead of loadUrl.
AssetManager assetManager = getAssets();
String htmlPage=null;
InputStream input;
try {
input = assetManager.open("python/index.html");
int size = input.available();
byte[] buffer = new byte[size];
input.read(buffer);
input.close();
// byte buffer into a string
htmlPage = new String(buffer);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
webView.loadDataWithBaseURL("file:///android_asset/", htmlPage, "text/html", "utf-8", "");
Note: jquery-1.8.2.min.js and jquery.mobile-1.3.2.min.js files should be present in your assets folder.
Hope this helps.

The problem was - I extracted those web files from a phonegap app's asset folder; those had some additional files ad different structure. That's why it was not working in Android naive environment !