I am trying to add Readability (a third party app) compatibility with my web browser, and I tracked down a bookmarklet to save a page to Readability:
javascript:(%28function%28%29%7Bwindow.baseUrl%3D%27http%3A//www.readability.com%27%3Bwindow.readabilityToken%3D%27bbRmvVb9nTNRWSVEGb9yrcFP4USUHnTjk2EVWXjn%27%3Bvar%20s%3Ddocument.createElement%28%27script%27%29%3Bs.setAttribute%28%27type%27%2C%27text/javascript%27%29%3Bs.setAttribute%28%27charset%27%2C%27UTF-8%27%29%3Bs.setAttribute%28%27src%27%2CbaseUrl%2B%27/bookmarklet/read.js%27%29%3Bdocument.documentElement.appendChild%28s%29%3B%7D%29%28%29)
however, I can't seem to get it to work. It works in desktop Safari and mobile/iPhone Safari. But both of the methods below do nothing:
[webview stringByEvaluatingJavaScriptFromString: readability];
[webview loadRequest: [NSURLRequest requestWithURL: [NSURL URLWithString: readability]]];
(readability is a string with the value above)
Is there another method to run javascript bookmarklets that I am unaware of or am I doing something wrong? Help is much appreciated.
Greg
You got this error is because the javascript url is encoded, you should decode the javascript string, (may be you use NSURL to pass the string, so it was encoded by NSURL)
then use the webview stringByEvaluatingJavaScriptFromString, this solution work well
-(void)loadUrl:(NSURL*)url
{
if ([[url scheme] isEqualToString:#"javascript"])
{
NSRange range = [[url absoluteString] rangeOfString:#"javascript:"];
NSString *javaScriptString = [[[url absoluteString] substringFromIndex:range.location + range.length] URLDecodedString];
[self stringByEvaluatingJavaScriptFromString:javaScriptString];
}
else
{
[self loadRequest:[NSURLRequest requestWithURL:url]];
}
}
You probably need to use their API. What you are trying to do is likely prevented for security reasons, and you need to put your own API key in the request.
Related
I've loaded a youtube embedded video to WKWebView:
https://www.youtube.com/embed/amtuB-2wGeQ?playsinline=1&autoplay=1
Then after WKWebView didFinishNavigation event is fired, I call:
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
webView.evaluateJavaScript("document.querySelector('video').play()", completionHandler: { (result, error) in
if let r = result {
print(r)
}
if let e = error {
print(e)
}
})
}
However, the javascript command is not being executed, both error and result are nil.
When I execute the same javascript command in Chrome developer tool, it successfully played the video and paused the video by calling "play()" and "pause()".
document.querySelector('video').play()
document.querySelector('video').pause()
I don't know what happened inside WKWebView, any ideas?
Thanks!
OK, finally figured out why it is not working.
If you are also struggling with "why my javascript is not working in WKWebView", below is a neat way to figure out why:
1. Open Safari on your desktop, Preferences -> Advanced, enable "show developer menu in menu bar"
2. In the Safari menu, Develop -> simulator, connect your iPhone simulator
3. Now you can see the web page html and script in Safari, in the console input area, try run different javascript to see which one works.
4. Then call the one that works from "evaluateJavaScript"
The reason why it didn't work from my case is that the embedded web page was rendered differently between common web browser and WKWebView. I took the browser script as example which didn't work.
With the help of Safari debugger, you can see what's really going on inside WKWebView, which is really cool.
Hope it helps if you ever run into the same problem.
Thanks!
Use UIWebView instead of WKWebView and use this code for play youtube video.
#pragma mark - Embed Video
- (UIWebView *)embedVideoYoutubeWithURL:(NSString *)urlString andFrame:(CGRect)frame {
NSString *videoID = [self extractYoutubeVideoID:urlString];
NSString *embedHTML = #"\
<html><head>\
<style type=\"text/css\">\
body {\
background-color: transparent;\
color: white;\
}\
</style>\
</head><body style=\"margin:0\">\
<embed id=\"yt\" src=\"http://www.youtube.com/v/%#\" type=\"application/x-shockwave-flash\" \
width=\"%0.0f\" height=\"%0.0f\"></embed>\
</body></html>";
NSString *html = [NSString stringWithFormat:embedHTML, videoID, frame.size.width, frame.size.height];
UIWebView *videoWebView = [[UIWebView alloc] initWithFrame:frame];
[videoWebView loadHTMLString:html baseURL:nil];
return videoWebView;
}
/**
#see https://devforums.apple.com/message/705665#705665
extractYoutubeVideoID: works for the following URL formats:
www.youtube.com/v/VIDEOID
www.youtube.com?v=VIDEOID
www.youtube.com/watch?v=WHsHKzYOV2E&feature=youtu.be
www.youtube.com/watch?v=WHsHKzYOV2E
youtu.be/KFPtWedl7wg_U923
www.youtube.com/watch?feature=player_detailpage&v=WHsHKzYOV2E#t=31s
youtube.googleapis.com/v/WHsHKzYOV2E
*/
- (NSString *)extractYoutubeVideoID:(NSString *)urlYoutube {
NSString *regexString = #"(?<=v(=|/))([-a-zA-Z0-9_]+)|(?<=youtu.be/)([-a-zA-Z0-9_]+)";
NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:regexString options:NSRegularExpressionCaseInsensitive error:&error];
NSRange rangeOfFirstMatch = [regex rangeOfFirstMatchInString:urlYoutube options:0 range:NSMakeRange(0, [urlYoutube length])];
if(!NSEqualRanges(rangeOfFirstMatch, NSMakeRange(NSNotFound, 0))) {
NSString *substringForFirstMatch = [urlYoutube substringWithRange:rangeOfFirstMatch];
return substringForFirstMatch;
}
return nil;
}
or use google's youtube-ios-player-helper pod
I'm trying to migrate from using a UIWebview to a WKWebview, and I need to invoke various Javascript functions that live in the webview.
In the UIWebview I have no trouble doing this, but the WKWebview throws an WKErrorDomain Error 4 for any and all calls. I thought it might be a race condition where I was calling functions that didn't exist in the DOM yet, but I added a debug statement to make those same calls once the page loaded and they're not working. I even did a 'document.body.innerHTML' which returned nil when there's clearly content being displayed in the webview.
The twist is that when inspecting the web code via Safari Web Inspector, everything works well and all calls work.
Why and how could this be? I do initialize the WKWebView with a WKWebViewConfiguration so that it'll share cookies across different webviews, so there might be something there, but I'm stumped.
This is how i initialize the WKWebView
WKWebViewConfiguration* config = [[WKWebViewConfiguration alloc] init];
config.processPool = [[WKProcessPool alloc] init];
WKUserContentController* userContentController = WKUserContentController.new;
WKUserScript * cookieScript = [[WKUserScript alloc] initWithSource: #"document.cookie = 'cookie1=value1; domain=blah; path=/;';" injectionTime:WKUserScriptInjectionTimeAtDocumentStart forMainFrameOnly:NO];
[userContentController addUserScript:cookieScript];
config.userContentController = userContentController;
WKWebView *webView = [[WKWebView alloc] initWithFrame:CGRectMake(0,0,50,50) configuration:config];
Here's a debugging statement where I log the document's innerHTML into the console log, which prints (nil) instead of the HTML.
NSLog(#"%#", [self.webView evaluateJavaScript:#"document.body.innerHTML" completionHandler:nil]);
WKWebView executes JS async unlike UIWebView; You cannot print like how you are doing..
Try this
[self.webView evaluateJavaScript:#"document.body.innerHTML" completionHandler:^(id result, NSError *error) {
NSLog(#"Error is %#",error);
NSLog(#"JS result %#" ,result);
}];
Im trying to execute javascript on iPhone by stringByEvaluatingJavaScriptFromString,
i made script
function execute() {
//dosent matter
alert('works');
}
execute();
This script works fine while using in developer console in safari.
But this way :
[self.webView1 stringByEvaluatingJavaScriptFromString:#"javascript: function execute() { alert('works');}execute();"];
Dosent work, i dont see alert, i tried also without "javascript:"
Thats confusing because im using stringByEvaluatingJavaScriptFromString with succes but without using function declaration.
[self.webView1 stringByEvaluatingJavaScriptFromString:#"alert('check');"];
works fine
If anyone is looking for answer, i have noticed that some functions could not work properly without putting them in file.js and then execute by using:
- (void)injectJavascript:(NSString *)resource {
NSString *jsPath = [[NSBundle mainBundle] pathForResource:resource ofType:#"js"];
NSString *js = [NSString stringWithContentsOfFile:jsPath encoding:NSUTF8StringEncoding error:NULL];
[self.webView1 stringByEvaluatingJavaScriptFromString:js];
}
I am writing an app for ios to extract information from a webpage, however, the relevant pieces on the page are built by javascript. So when it is loaded by webview, the javascript is executed and the information displays no problem. If I try to load the page into a string by using the following method, the javascript is loaded, but not actually executed, therefore the string has no useful data in it.
NSData *urlData = [NSData dataWithContentsOfURL:[NSURL URLWithString:fullURL]];
NSString *responseString = [[NSString alloc] initWithData:urlData encoding:NSUTF8StringEncoding];
Is there another way besides loading the page into webview and exporting it from there? If not, how do you do that?
I'm not sure if there's another way outside of letting the UIWebView execute the JS and render the page, but if you do end up going this route, you could just grab the HTML of the whole page and pass that to the native end like so:
[dummyWebView stringByEvaluatingJavaScriptFromString:#"document.getElementsByTagName('html')[0].outerHTML;"];
Listening to the window.load event might be better to know when the page has finished going through all the JS
Good luck!
You set delegate to webView: self.webView.delegate = self; and implement UIWebViewDelegate:
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
NSString *html = [webView stringByEvaluatingJavaScriptFromString:#"document.documentElement.outerHTML"];
NSLog(#"html1 = %#", html);
// or use
NSString *html2 = [webView stringByEvaluatingJavaScriptFromString:#"document.body.innerHTML"];
NSLog(#"html2 = %#", html2);
}
<script language="javascript">
alert("Hell! UIWebView!");
</script>
I can see the alert message inside my UIWebView but can I handle this situation?
Update:
I'm loading a web-page into my UIWebView:
- (void)login {
NSString *requestText = [[NSString alloc] initWithFormat: #"%#?user=%#&password=%#", DEFAULT_URL, user.name, user.password]; // YES, I'm using GET request to send password :)
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:requestText]];
[webView loadRequest:request];
}
The target page contain a JS. If user name or password is incorrect this JS show alert.
I have not any access to its sources.
I want to handle it inside my UIWebViewDelegate.
A better solution to this problem is to create a Category for UIWebView for the method
webView:runJavaScriptAlertPanelWithMessage:initiatedByFrame:
So that you can handle the alert event in any way that you'd like. I did this because I don't like the default behavior of UIWebView when it puts the filename of the source in the UIAlertView title. The Category looks something like this,
#interface UIWebView (JavaScriptAlert)
- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame;
#end
#implementation UIWebView (JavaScriptAlert)
- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WebFrame *)frame {
UIAlertView* dialogue = [[UIAlertView alloc] initWithTitle:nil message:message delegate:nil cancelButtonTitle:#"Okay" otherButtonTitles:nil];
[dialogue show];
[dialogue autorelease];
}
#end
This seems to do it:
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
JSContext *ctx = [webView valueForKeyPath:#"documentView.webView.mainFrame.javaScriptContext"];
ctx[#"window"][#"alert"] = ^(JSValue *message) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"JavaScript Alert" message:[message toString] delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert show];
};
}
Note: only tested on iOS 8.
If by "contain a flash" you mean the page you're loading into your web view has an Adobe Flash movie in it, you're out of luck, I'm afraid. Mobile Safari doesn't support Flash, and most likely never will.
In the general case, if you want JavaScript running in a web view to communicate with the native app hosting it, you can load fake URLs (for example: "myapp://alert?The+text+of+the+alert+goes+here."). That will trigger the webView:shouldStartLoadWithRequest:navigationType: delegate method. In that method, inspect the request, and if the URL being loaded is one of these internal communications, trigger the appropriate action in your app, and return NO.