Can an external JS be injected into the Web View inside an iOS app (wkwebview to be specific), then executed?
Not adblock api for safari - but imagine simple JS/JQ that does the same. Find a class, changes the class.
Can this be done? If so - are there limitations to what types of Javascript can be executed in the WkWebview?
If you have a local JavaScript file that you want to load in and use. Similar to adding a
<script src="file.js" />
you can use this in swift
let root = NSBundle.mainBundle().resourceURL!
let JSURL = root.URLByAppendingPathComponent("file.js")
let JSString = try! String(contentsOfURL: JSURL)
let WKJS = WKUserScript(source: JSString, injectionTime: WKUserScriptInjectionTime.AtDocumentStart, forMainFameOnly: false)
webView.configuration.userContentController.addUserScript(WKJS)
For WKWebView, you have the following instance methods to execute Javascript. The JS to be execute has to be sent as a NSString to the methods.
Obj-C
- (void)evaluateJavaScript:(NSString *)javaScriptString
completionHandler:(void (^)(id,
NSError *error))completionHandler
Swift
func evaluateJavaScript(_ javaScriptString: String,
completionHandler completionHandler: ((AnyObject?,
NSError?) -> Void)?)
Reference: https://developer.apple.com/library/ios/documentation/WebKit/Reference/WKWebView_Ref/index.html#//apple_ref/occ/instm/WKWebView/evaluateJavaScript:completionHandler:
I am trying to wrap my head around establishing communication between an HTML page in a webview in Nashorn and the host nashorn application. I read this tutorial
here
but I can't seem to get how to create a callback which I can call inside the HTML page to run something in the host. The wrapping function works fine I just don't know where to go from here to get webview html to host communication. No matter how I do it, I get an empty object but no methods.
This.engine.loadWorker.stateProperty().addListener(new ChangeListener() {
changed: function(value, oldState, newState) {
if (newState == Worker.State.SUCCEEDED) {
function testObj(){
this.foo = function(){
print('hello');
}
}
This.document = wrap(This.engine.executeScript("document"));
This.window = wrap(This.engine.executeScript("window"));
I tried
This.window.setMember('HOST',new testObj());
and
This.window.setMember('HOST',wrap(new testObj()));
Both get me nothing in the window
This.window.executeScript("window").setMember('HOST',new testObj());
Gets me an empty object in the HTML page javascript "{}"
I'm using UIWebView in a project. Sometimes it doesn't call the webViewDidFinishLoad method. Because the web page have some javascripts. The method
- (BOOL) webView: (UIWebView *) webView shouldStartLoadWithRequest: (NSURLRequest *) request navigationType: (UIWebViewNavigationType) navigationType
is getting call but webViewDidFinishLoad doesn't. I want to catch that method. Because I'm start an animation when the webview start loading. Then I want to stop this animation when it finished. It's not working with websites having javascript content. Any one have an idea please?
Thanks
webViewDidFinishLoad method gets called when the UIWebView has finished loading the url, in your case since you are calling a javascript, it doesn't load your content, it just calls a javascript function in your already loaded webview. But YES you can catch the javascript actions in the same method you stated as below
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{
NSString *url = [[request URL] absoluteString];
if(navigationType == UIWebViewNavigationTypeLinkClicked){
if([url rangeOfString:#"SOMETHING"].length > 0 ){
//if your action returns something appended in your url like the anchors work
//DO YOUR STUFFS
}
}
return TRUE;
}
apparently, the webview in ios checks specifically for "iframe" tags in the html's dom and in case it finds, it creates events based on that tag as well. therefore, a simple however a patchy solution would be adding the following code in the part of the dom that is changing (for example, in the actual template of each section):
<iframe></iframe>
did the trick for me..
Is it possible to detect if the user is accessing through the browser or application using JavaScript?
I'm developing a hybrid application to several mobile OS through a web page and a PhoneGap application and the goal would be to:
Use the same code independently of the deployment target
Add PhoneGap.js file only when the user agent is an application
You could check if the current URL contains http protocol.
var app = document.URL.indexOf( 'http://' ) === -1 && document.URL.indexOf( 'https://' ) === -1;
if ( app ) {
// PhoneGap application
} else {
// Web page
}
Quick solution comes to mind is,
onDeviceReady
shall help you. As this JS call is invoked only by the Native bridge (objC or Java), the safari mobile browser will fail to detect this. So your on device app(phone gap) source base will initiate from onDeviceReady.
And if any of the Phonegap's JS calls like Device.platform or Device.name is NaN or null then its obviously a mobile web call.
Please check and let me know the results.
I figured out a way to do this and not rely on deviceready events thus, keeping the web codebase intact...
The current problem with using the built in deviceready event, is that when the page is loaded, you have no way of telling the app: "Hey this is NOT running on an mobile device, there's no need to wait for the device to be ready to start".
1.- In the native portion of the code, for example for iOS, in MainViewController.m there's a method viewDidLoad, I am sending a javascript variable that I later check for in the web code, if that variable is around, I will wait to start the code for my page until everything is ready (for example, navigator geolocation)
Under MainViewController.m:
- (void) viewDidLoad
{
[super viewDidLoad];
NSString* jsString = [NSString stringWithFormat:#"isAppNative = true;"];
[self.webView stringByEvaluatingJavaScriptFromString:jsString];
}
2.- index.html the code goes like this:
function onBodyLoad()
{
document.addEventListener("deviceready", onDeviceReady, false);
}
function onDeviceReady(){;
myApp.run();
}
try{
if(isAppNative!=undefined);
}catch(err){
$(document).ready(function(){
myApp.run();
});
}
PhoneGap has window.PhoneGap (or in Cordova, it's window.cordova or window.Cordova) object set. Check whether that object exists and do the magic.
Inside the native call where the url for the phonegap app is loaded you add a parameter target with value phonegap. So the call for android becomes something like this.
super.loadUrl("file:///android_asset/www/index.html?target=phonegap");
Your website using this code won't be called with the extra parameter, so we now have something different between the two deploying platforms.
Inside the javascript we check if the parameter exists and if so we add the script tag for phonegap/cordova.
var urlVars = window.location.href.split('?');
if(urlVars.length > 1 && urlVars[1].search('target=phonegap') != -1){
//phonegap was used for the call
$('head').append('<script src="cordova.js"></script>');
}
A small caveat: this method requires to change the call to index.html in phonegap for each different targeted mobile platform. I am unfamiliar where to do this for most platforms.
what if you try following :
if(window._cordovaNative) {
alert("loading cordova");
requirejs(["...path/to/cordova.js"], function () {
alert("Finished loading cordova");
});
}
I am using the same code for both phonegap app and our web client. Here is the code that I use to detect if phonegap is available:
window.phonegap = false;
$.getScript("cordova-1.7.0.js", function(){
window.phonegap = true;
});
Keep in mind that phonegap js file is loaded asynchronously. You can load it synchronously by setting the correct option of a nifty jquery $.getScript function.
Note that approach does make an extra GET request to grab phonegap js file even in your webclient. In my case, it did not affect the performance of my webclient; so it ended up being a nice/clean way to do this.Well at least until someone else finds a quick one-line solution :)
It sounds like you are loading another webpage once the webview starts in the Phonegap app, is that correct? If that's true then you could add a param to the request url based on configuration.
For example, assuming PHP,
App.Config = {
target: "phonegap"
};
<body onload="onbodyload()">
var onbodyload = function () {
var target = App.Config.target;
document.location = "/home?target=" + target;
};
Then on the server side, include the phonegap js if the target is phonegap.
There is no way to detect the difference using the user agent.
The way I'm doing it with is using a global variable that is overwritten by a browser-only version of cordova.js. In your main html file (usually index.html) I have the following scripts that are order-dependent:
<script>
var __cordovaRunningOnBrowser__ = false
</script>
<script src="cordova.js"></script> <!-- must be included after __cordovaRunningOnBrowser__ is initialized -->
<script src="index.js"></script> <!-- must be included after cordova.js so that __cordovaRunningOnBrowser__ is set correctly -->
And inside cordova.js I have simply:
__cordovaRunningOnBrowser__ = true
When building for a mobile device, the cordova.js will not be used (and instead the platform-specific cordova.js file will be used), so this method has the benefit of being 100% correct regardless of protocols, userAgents, or library variables (which may change). There may be other things I should include in cordova.js, but I don't know what they are yet.
Ive ben struggling with this aswell, and i know this is an old thread, but i havent seen my approach anywhere, so thought id share incase itll help someone.
i set a custom useragent after the actual useragent :
String useragent = settings.getUserAgentString();
settings.setUserAgentString(useragent + ";phonegap");
that just adds the phonegap string so other sites relying on detecting your mobile useragent still works.
Then you can load phonegap like this:
if( /phonegap/i.test(navigator.userAgent) )
{
//you are on a phonegap app, $getScript etc
} else {
alert("not phonegap");
}
To my mind you try to make issue for self. You didn't mentioned your development platform but most of them have different deployment configuration. You can define two configurations. And set variable that indicates in which way code was deployed.
In this case you don't need to care about devices where you deployed your app.
Short and effective:
if (document.location.protocol == 'file:') { //Phonegap is present }
Similar to B T's solution, but simpler:
I have an empty cordova.js in my www folder, which gets overwritten by Cordova when building. Don't forget to include cordova.js before your app script file (it took my one hour to find out that I had them in wrong order...).
You can then check for the Cordova object:
document.addEventListener('DOMContentLoaded', function(){
if (window.Cordova) {
document.addEventListener('DeviceReady', bootstrap);
} else {
bootstrap();
}
});
function bootstrap() {
do_something()
}
New solution:
var isPhoneGapWebView = location.href.match(/^file:/); // returns true for PhoneGap app
Old solution:
Use jQuery, run like this
$(document).ready(function(){
alert(window.innerHeight);
});
Take iPhone as example for your mobile application,
When using PhoneGap or Cordova, you'll get 460px of WebView, but in safari, you'll lose some height because of browser's default header and footer.
If window.innerHeight is equal to 460, you can load phonegap.js, and call onDeviceReady function
Nobody mentioned this yet, but it seems Cordova now supports adding the browser as a platform:
cordova platforms add browser
This will automatically add cordova.js during run-time, which features the onDeviceReady event, so that you do not need to fake it. Also, many plugins have browser support, so no more browser hacks in your code.
To use your app in the browser, you should use cordova run browser. If you want to deploy it, you can do so using the same commands as the other platforms.
EDIT: forgot to mention my source.
Solution: Patch index.html in Cordova and add cordova-platform="android" to <html> tag, so that cordova-platform attribute will be only present in Cordova build and missing from original index.html used for web outside of Cordova.
Pros: Not rely on user agent, url schema or cordova API. Does not need to wait for deviceready event. Can be extended in various ways, for example cordova-platform="browser" may be included or not, in order to distinguish between web app outside of Cordova with Cordova's browser platform build.
Merge with config.xml
<platform name="android">
<hook src="scripts/patch-android-index.js" type="after_prepare" />
</platform>
Add file scripts/patch-android-index.js
module.exports = function(ctx) {
var fs = ctx.requireCordovaModule('fs');
var path = ctx.requireCordovaModule('path');
var platformRoot = path.join(ctx.opts.projectRoot, 'platforms/android');
var indexPath = platformRoot + '/app/src/main/assets/www/index.html';
var indexSource = fs.readFileSync(indexPath, 'utf-8');
indexSource = indexSource.replace('<html', '<html cordova-platform="android"');
fs.writeFileSync(indexPath, indexSource, 'utf-8');
}
Notes: For other than android, the paths platforms/android and /app/src/main/assets/www/index.html should be adjusted.
App can check for cordova-platform with
if (! document.documentElement.getAttribute('cordova-platform')) {
// Not in Cordova
}
or
if (document.documentElement.getAttribute('cordova-platform') === 'android') {
// Cordova, Android
}
I have been able to get content out of WebView using javascript and loadUrl() method having specified an interface thats called from javascript string that is injected into WebView.The problem is that this only works for me when the loadUrl() method is present in onPageFinished() method in the WebView client. What I want to do is I want to get the content out of the WebView (with the content already loaded). The WebView is in an activity instrumentation test case and I can for instance use findAll() method and that works fine. For some reason I can not use loadUrl() and get the desired behaviour (which is injecting javascript and getting content out of the WebView with a help of an interface).
PLease help.
Thanks
Pawel
EDIT:
Just adding code to show what I am doing exactly:
Yes I understand that but my problem is that I am trying to do it within a test case this way:
public void testWebView() throws Exception {
solo.sleep(3000); // wait for views to load on the screen
WebView a=null;
ArrayList<View> views = solo.getCurrentViews(); // I am using solo object to get views for the screen currently loaded
for(View s:views)
{
if (s instanceof WebView)
{
a = (WebView)s; // this is where I get my WebView
}
}
Instrumentation inst = getInstrumentation();
inst.runOnMainSync(new Runnable()
{
public void run()
{
int d =a.findAll("something"); // this method runs fine on the object and i get the desired result
WebSettings settings = a.getSettings();
settings.setJavaScriptEnabled(true);
a.loadUrl("javascript:document.location = document.getElementById('google').getAttribute('href')"); // this javascript is never executed and that is my problem
}
});
}
You can inject javascript in a loaded page much the same way you can do it in desktop browsers - via inline javascript entered into navigation bar.
Bind some Java object so that it can be called from Javascript with WebView:
addJavascriptInterface(javaObjectExposed, "JSname")
Force execute javascript within an existing page by
WebView.loadUrl("javascript:window.JSname.passData("some data from page");");