Pass JavaScript variable to Swift
How would I go about changing the value of a Swift variable based on a JavaScript variable? (Passing a JavaScript variable to Swift)
My goal is simply to conduct an if statement using a JavaScript variable, and than edit the swift variable based on that.
Example in code of what I am trying to do:
var checkElement = false
webView.evaluateJavaScript("var element = document.getElementById("element");"){ (value, error) in
if let err = error {
print(err)
}
}
if (element != null){
checkElement = true
}
I understand this won't work due to element only existing in JavaScript. Although, how would I pass the element variable to Swift?
javascript ios swift webkit
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
add a comment |
How would I go about changing the value of a Swift variable based on a JavaScript variable? (Passing a JavaScript variable to Swift)
My goal is simply to conduct an if statement using a JavaScript variable, and than edit the swift variable based on that.
Example in code of what I am trying to do:
var checkElement = false
webView.evaluateJavaScript("var element = document.getElementById("element");"){ (value, error) in
if let err = error {
print(err)
}
}
if (element != null){
checkElement = true
}
I understand this won't work due to element only existing in JavaScript. Although, how would I pass the element variable to Swift?
javascript ios swift webkit
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
add a comment |
How would I go about changing the value of a Swift variable based on a JavaScript variable? (Passing a JavaScript variable to Swift)
My goal is simply to conduct an if statement using a JavaScript variable, and than edit the swift variable based on that.
Example in code of what I am trying to do:
var checkElement = false
webView.evaluateJavaScript("var element = document.getElementById("element");"){ (value, error) in
if let err = error {
print(err)
}
}
if (element != null){
checkElement = true
}
I understand this won't work due to element only existing in JavaScript. Although, how would I pass the element variable to Swift?
javascript ios swift webkit
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
How would I go about changing the value of a Swift variable based on a JavaScript variable? (Passing a JavaScript variable to Swift)
My goal is simply to conduct an if statement using a JavaScript variable, and than edit the swift variable based on that.
Example in code of what I am trying to do:
var checkElement = false
webView.evaluateJavaScript("var element = document.getElementById("element");"){ (value, error) in
if let err = error {
print(err)
}
}
if (element != null){
checkElement = true
}
I understand this won't work due to element only existing in JavaScript. Although, how would I pass the element variable to Swift?
javascript ios swift webkit
javascript ios swift webkit
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
edited Apr 12 '18 at 19:50
Swift Geek
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
asked Apr 12 '18 at 19:40
Swift GeekSwift Geek
148111
148111
add a comment |
add a comment |
3 Answers
3
active
oldest
votes
You can get variable in Swift code by interception clicked URL via UIWebViewDelegate method webView:shouldStartLoadWithRequest:navigationType:
Simulate click you can via iframe in JS.
Here is an example in Objective-C, but it will be same on Swift -
http://iwearshorts.com/blog/how-to-call-uiwebview-from-javascript/
answered Apr 12 '18 at 21:10
shshshshshsh
164
add a comment |
You can get the variable by following code.
let element = webView.stringByEvaluatingJavaScriptFromString("document.getElementById("element")")
if element != nil{
checkElement = true
}else{
print("Error")
}
for further understanding you can refer post by Perry Mitchell
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
add a comment |
I thought I would answer this myself.
First, ensure your class is conforming to the correct protocols: WKScriptMessageHandler is required and you may also need WKNavigationDelegate.
Before initializing your WKWebView add a userContentController to its configuration. This is what will act as a 'bridge' from your JavaScript to Swift.
var webView = WKWebView()
let configuration = WKWebViewConfiguration()
configuration.userContentController.add(self, name: "messageName")
webView = WKWebView(frame: .zero, configuration: configuration)
Now initialize the userContentController() function and handle the received content within it. Ex.
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Name: (message.name)")
print("Body: (message.body as! String)")
}
Now within the JavaScript inside your evaluateJavaScript() add the following line to push whatever data to Swift:
window.webkit.messageHandlers['messageName'].postMessage('Message Body!');
Now, when that JavaScript line is called Swift will output the following:
Name: messageName
Body: Message Body!
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
You can get variable in Swift code by interception clicked URL via UIWebViewDelegate method webView:shouldStartLoadWithRequest:navigationType:
Simulate click you can via iframe in JS.
Here is an example in Objective-C, but it will be same on Swift -
http://iwearshorts.com/blog/how-to-call-uiwebview-from-javascript/
answered Apr 12 '18 at 21:10
shshshshshsh
164
add a comment |
You can get variable in Swift code by interception clicked URL via UIWebViewDelegate method webView:shouldStartLoadWithRequest:navigationType:
Simulate click you can via iframe in JS.
Here is an example in Objective-C, but it will be same on Swift -
http://iwearshorts.com/blog/how-to-call-uiwebview-from-javascript/
answered Apr 12 '18 at 21:10
shshshshshsh
164
add a comment |
You can get variable in Swift code by interception clicked URL via UIWebViewDelegate method webView:shouldStartLoadWithRequest:navigationType:
Simulate click you can via iframe in JS.
Here is an example in Objective-C, but it will be same on Swift -
http://iwearshorts.com/blog/how-to-call-uiwebview-from-javascript/
answered Apr 12 '18 at 21:10
shshshshshsh
164
You can get variable in Swift code by interception clicked URL via UIWebViewDelegate method webView:shouldStartLoadWithRequest:navigationType:
Simulate click you can via iframe in JS.
Here is an example in Objective-C, but it will be same on Swift -
http://iwearshorts.com/blog/how-to-call-uiwebview-from-javascript/
answered Apr 12 '18 at 21:10
shshshshshsh
164
answered Apr 12 '18 at 21:10
shshshshshsh
164
answered Apr 12 '18 at 21:10
shshshshshsh
164
answered Apr 12 '18 at 21:10
shshshshshsh
164
164
add a comment |
add a comment |
You can get the variable by following code.
let element = webView.stringByEvaluatingJavaScriptFromString("document.getElementById("element")")
if element != nil{
checkElement = true
}else{
print("Error")
}
for further understanding you can refer post by Perry Mitchell
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
add a comment |
You can get the variable by following code.
let element = webView.stringByEvaluatingJavaScriptFromString("document.getElementById("element")")
if element != nil{
checkElement = true
}else{
print("Error")
}
for further understanding you can refer post by Perry Mitchell
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
add a comment |
You can get the variable by following code.
let element = webView.stringByEvaluatingJavaScriptFromString("document.getElementById("element")")
if element != nil{
checkElement = true
}else{
print("Error")
}
for further understanding you can refer post by Perry Mitchell
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
You can get the variable by following code.
let element = webView.stringByEvaluatingJavaScriptFromString("document.getElementById("element")")
if element != nil{
checkElement = true
}else{
print("Error")
}
for further understanding you can refer post by Perry Mitchell
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
answered Apr 12 '18 at 21:17
PrajaktaPrajakta
17514
17514
add a comment |
add a comment |
I thought I would answer this myself.
First, ensure your class is conforming to the correct protocols: WKScriptMessageHandler is required and you may also need WKNavigationDelegate.
Before initializing your WKWebView add a userContentController to its configuration. This is what will act as a 'bridge' from your JavaScript to Swift.
var webView = WKWebView()
let configuration = WKWebViewConfiguration()
configuration.userContentController.add(self, name: "messageName")
webView = WKWebView(frame: .zero, configuration: configuration)
Now initialize the userContentController() function and handle the received content within it. Ex.
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Name: (message.name)")
print("Body: (message.body as! String)")
}
Now within the JavaScript inside your evaluateJavaScript() add the following line to push whatever data to Swift:
window.webkit.messageHandlers['messageName'].postMessage('Message Body!');
Now, when that JavaScript line is called Swift will output the following:
Name: messageName
Body: Message Body!
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
add a comment |
I thought I would answer this myself.
First, ensure your class is conforming to the correct protocols: WKScriptMessageHandler is required and you may also need WKNavigationDelegate.
Before initializing your WKWebView add a userContentController to its configuration. This is what will act as a 'bridge' from your JavaScript to Swift.
var webView = WKWebView()
let configuration = WKWebViewConfiguration()
configuration.userContentController.add(self, name: "messageName")
webView = WKWebView(frame: .zero, configuration: configuration)
Now initialize the userContentController() function and handle the received content within it. Ex.
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Name: (message.name)")
print("Body: (message.body as! String)")
}
Now within the JavaScript inside your evaluateJavaScript() add the following line to push whatever data to Swift:
window.webkit.messageHandlers['messageName'].postMessage('Message Body!');
Now, when that JavaScript line is called Swift will output the following:
Name: messageName
Body: Message Body!
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
add a comment |
I thought I would answer this myself.
First, ensure your class is conforming to the correct protocols: WKScriptMessageHandler is required and you may also need WKNavigationDelegate.
Before initializing your WKWebView add a userContentController to its configuration. This is what will act as a 'bridge' from your JavaScript to Swift.
var webView = WKWebView()
let configuration = WKWebViewConfiguration()
configuration.userContentController.add(self, name: "messageName")
webView = WKWebView(frame: .zero, configuration: configuration)
Now initialize the userContentController() function and handle the received content within it. Ex.
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Name: (message.name)")
print("Body: (message.body as! String)")
}
Now within the JavaScript inside your evaluateJavaScript() add the following line to push whatever data to Swift:
window.webkit.messageHandlers['messageName'].postMessage('Message Body!');
Now, when that JavaScript line is called Swift will output the following:
Name: messageName
Body: Message Body!
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
I thought I would answer this myself.
First, ensure your class is conforming to the correct protocols: WKScriptMessageHandler is required and you may also need WKNavigationDelegate.
Before initializing your WKWebView add a userContentController to its configuration. This is what will act as a 'bridge' from your JavaScript to Swift.
var webView = WKWebView()
let configuration = WKWebViewConfiguration()
configuration.userContentController.add(self, name: "messageName")
webView = WKWebView(frame: .zero, configuration: configuration)
Now initialize the userContentController() function and handle the received content within it. Ex.
public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print("Name: (message.name)")
print("Body: (message.body as! String)")
}
Now within the JavaScript inside your evaluateJavaScript() add the following line to push whatever data to Swift:
window.webkit.messageHandlers['messageName'].postMessage('Message Body!');
Now, when that JavaScript line is called Swift will output the following:
Name: messageName
Body: Message Body!
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
edited Nov 26 '18 at 3:31
Stephen Rauch
30.1k153758
30.1k153758
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
answered Nov 26 '18 at 2:50
Swift GeekSwift Geek
148111
148111
add a comment |
add a comment |
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