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[Android ]How to get redirected url on Android app

in android app, I want to get redirected URL
in my app, I want to play HLS(.m3u8) file
before access to HLS's URL we access other URL to redirect.
I coded as below but it doesn't work
val conn = url.openConnection() as HttpURLConnection
conn.instanceFollowRedirects
conn.connect()
val inputStream :InputStream = con.inputStream
mediaPlayer.setDataSource(con.url.path)
inputStream.close()
I tried direct url to .m3u8 and it works as below
mediaPlayer.setDataSource(con.url.path)

Check your HTTP Response. If the status code is between 300 and 399 it means that the page is being redirected to another page. To determine the destination read the "Location" header field:
object RedirectHelper {
fun getRedirectUrl(connection: HttpURLConnection): String? {
val code = connection.responseCode
return if (code in 300..399) {
connection.getHeaderField("Location")
} else null
}
}

error of shouldInterceptRequest in *.apk ( Ionic with asp.net mvc OAuth )

I just builded an app by ionic-framework. The server side is:
bitoftech.net/2014/06/01/token-based-authentication-asp-net-web-api-2-owin-asp-net-identity
All function works fine in the PC chrome browser, authorization pass and request all get correct response.
Request success screen
but once we builded the html5 and angularjs files into apk, function fails.
ionic build android
ionic run android
Got the Error screen by chrome inspect plugin.
There a similar question here. I also tried that way but also can't work.
Client-Via:shouldInterceptRequest
In index.html file there a cross domain js reference also failed.
I find this might relate to shouldInterceptRequest method in SystemWEbViewClient.java
I common few no use code and just direct response the result, finally the js reference successed.
but the auth request still failed
and I am not sure whether this is a best way to solve the problem.

I just comment the code below which in shouldInterceptRequest method, then it all works.
public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
try {
// Check the against the whitelist and lock out access to the WebView directory
// Changing this will cause problems for your application
// *********************** below four lines of code commented.-----
// if (!parentEngine.pluginManager.shouldAllowRequest(url)) {
// LOG.w(TAG, "URL blocked by whitelist: " + url);
// Results in a 404.
// return new WebResourceResponse("text/plain", "UTF-8", null);
// }
CordovaResourceApi resourceApi = parentEngine.resourceApi;
Uri origUri = Uri.parse(url);
// Allow plugins to intercept WebView requests.
Uri remappedUri = resourceApi.remapUri(origUri);
if (!origUri.equals(remappedUri) || needsSpecialsInAssetUrlFix(origUri) || needsKitKatContentUrlFix(origUri)) {
CordovaResourceApi.OpenForReadResult result = resourceApi.openForRead(remappedUri, true);
return new WebResourceResponse(result.mimeType, "UTF-8", result.inputStream);
}
// If we don't need to special-case the request, let the browser load it.
return null;
} catch (IOException e) {
if (!(e instanceof FileNotFoundException)) {
LOG.e(TAG, "Error occurred while loading a file (returning a 404).", e);
}
// Results in a 404.
return new WebResourceResponse("text/plain", "UTF-8", null);
}
}

How to add a protocol to a URL if it does not exist? (in an Android app)

I am working on an app that gets a URL link from the user via edit text widget. How can I check if a given URL has a protocol? And if it doesn't, how can I add the correct protocol for the specific URL?
For example if the user entered: google.com
how can I make it become: https://google.com
The main problem is knowing the correct URL protocol for a given address (is it http/https/ftp? and so on).

You can use String.startsWith() to check if the url String starts with http:// or not
public String valid_url(final String url)
{
if (!url.startsWith("http://") && !url.startsWith("https://"))
{
return "http://" + url;
}
return url;
}

first check if url has protocol using .contains() method
and get protocol using .indexof() and .substring() method
string url = editText.getText().toString();
string protocol;
if(url.contains("://")){
//url has a protocol
int index = url.indexof("://");
//get protocol
protocol = url.substring(0,index-1);
}else{
//url does not have a protocal
// add your protocol to begining of the url
}

You can use android web kit URLUTIL class
package android.webkit;
URLUtil.guessUrl("your web address/String")
example scenarios:
www.testurl.com
testurl.com
testurl
result:
http://www.testurl.com/

Just compare the your output string with .contains() property
String value = editText.getText().toString();
if(!value.contains("https://")) {
// add https:// to ur string
}else {
// No need to add
}

This solution worked for me:
if(!url.startsWith("www.")&& !url.startsWith("http://") && !url.startsWith("https://")){
url = "www."+url;
}
if(!url.startsWith("http://") && !url.startsWith("https://")){
url = "http://"+url;
}
Hope this will help you.

As already adviced use the URL class of the SDK.
Here an example:
var urlWithScheme = new URL("https://www.google.com");
var urlWithoutScheme = new URL("www.google.com");
if (urlWithScheme.getProtocol() != null && urlWithScheme.getProtocol().length() > 0) {
System.out.println("Given URL includes scheme: " + urlWithScheme.getProtocol());
}
if (urlWithoutScheme.getProtocol() != null && urlWithoutScheme.getProtocol().length() > 0) {
System.out.println("Given URL includes scheme: " + urlWithoutScheme.getProtocol());
} else {
System.out.println("Url has no Protocol and you can't guess it by the domain name, because under this name all possible services can exist!");
}
If the given URL has not protocoll you can't guess it. Because under a domain name there can exist any protocol specific service in parrallel.
I would narrow it down to only support http and https. For this you could write a test like connect to https url, if success use it, because https is prefered. If you get redirect or not connection try http ;)

Validate Specfic URL input in EditText for android

My application is about downloading an image from a specific website e.g. www.example.com/img-...
The user will input the url for the img to the EditText field. e.g. www.example.com/img-123
My problem is that when the user inputs a wrong URL, i.e. one with no no image, it is empty e.g. www.example.com/img-222
I want to detect this and tell the user their input does not link to an image and try again.
I'm using the isValidUrl() function to detect if the input is a WEB_URL only but what I want is that when the entered url has no image, the program should tell them it is an incorrect format for url.
I'm using Jsoup.connect(url).get(); to connect to the url and get the image and save it
private boolean isValidUrl(String url) {
Pattern p = Patterns.WEB_URL;
Matcher m = p.matcher(url);
if(m.matches())
return true;
else
return false;
}

We can use android native android.webkit.URLUtil class to validate any kind of url.
URLUtil.isValidUrl(downloadImaheEditText.getText().toString());
it will return true if valid else false.

String[] schemes = {"http","https"}; //DEFAULT schemes = "http", "https", "ftp"
UrlValidator urlValidator = new UrlValidator(schemes);
if (urlValidator.isValid("http://www.google.com")) {
//url is valid
}else{
//url is invalid
}
Use Apache commons-validator URLValidator class

I tried this and it worked for me. Please find the code snippet below:
public static boolean isURL(String url) {
Pattern p = Patterns.WEB_URL;
Matcher m = p.matcher(url.toLowerCase());
return m.matches();
}

Application Error on Android Cordova/Phonegap Application

I have a cordova (2.7.0) android app that is crashing with an Application Error when it tries to load an iframe where the source has a protocol relative (network-path reference) src.
For instance, if the iframe is:
<iframe src="//instagram.com/p/beGdCuhQYl/embed/?wmode=opaque&wmode=opaque" width="800" height="928" style="border:0;" frameborder="0"></iframe>
Then the app tries to load the source from
file://instagram.com/p/beGdCuhQYl/embed/?wmode=opaque&wmode=opaque
Since the html page that loads this iframe is loaded from the file system, it makes sense that it is doing this. However, is there a way to stop the app from crashing? The same cordova app on iOS just doesn't load anything, and has a blank iframe. I would be nice if the android app behaved the same way.
It would be even nicer if there was a way to tell the cordova app to load these types of urls from http:// and not file:// but I think that is asking too much.

Ok, so I ended up doing this in two parts. First part, try to fix as many protocol relative urls as possible in javascript, and the second part was to provide some java code to ignore any that I missed.
First part (uses jQuery)
/**
* Takes text, looks for elements with src attributes that are
* protocol relative (//) and converts them to http (http://)
* #param {String} text the text that you want to fix urls in
* #returns {String} the updated text with corrected urls
*/
fixProtocolRelativeUrlsInText: function(text) {
var $html, $elements;
try {
$html = $('<div>' + text + '</div>');
$elements = $html.find('[src^="//"]');
if ($elements.length) {
$elements.each(function() {
var $this = $(this);
$this.attr('src', 'http:' + $this.attr('src'));
});
return $html.html();
} else {
return text;
}
} catch(ex) {
return text;
}
},
Second part:
/**
* Override the default makeWebViewClient and provide a custom handler for protocol
* relative urls.
*/
#Override
public CordovaWebViewClient makeWebViewClient(CordovaWebView webView) {
//
// We already try to fix protocol relative urls in the javascript. But this is a safety net in case anything
// gets through. So, in order to not crash the app, lets handle these types ourself and just swallow them up
// for now. The url won't load but at least it won't crash the app either. By the time the protocol relative
// url gets in here, it has the file: appended to it already. If it was a true file:// path to something on the
// device, then it will have file:///some/path, and if it was a protocol relative url that was converted to a
// file:// then it will have file://some.domain, so we look for urls that don't have the three /'s
//
final Pattern pattern = Pattern.compile("^file://[^/].*$");
CordovaWebViewClient webViewClient;
if(android.os.Build.VERSION.SDK_INT < android.os.Build.VERSION_CODES.HONEYCOMB) {
webViewClient = new CordovaWebViewClient(this, webView) {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
Matcher matcher = pattern.matcher(url);
if (matcher.matches()) {
Log.i(LOG_TAG, "swallowing url '" + url + "'");
return true;
} else {
return super.shouldOverrideUrlLoading(view, url);
}
}
};
} else {
webViewClient = new IceCreamCordovaWebViewClient(this, webView) {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
Matcher matcher = pattern.matcher(url);
if (matcher.matches()) {
Log.i(LOG_TAG, "swallowing url '" + url + "'");
return true;
} else {
return super.shouldOverrideUrlLoading(view, url);
}
}
};
}
return webViewClient;
}

Cordova doesn't support protocol relative src, it expects you to specify either file, or http.