Alert dialog from was blocked

Dart doesn't show the alert dialog when I use a webview and show this error:

: An alert dialog was blocked. (extensions::webViewEvents:225)

: A confirm dialog was blocked. (extensions::webViewEvents:225)

Does anyone know how to bypass the problem or how to catch the error?


Sorry for my bad English.


The code used:

Element webview= querySelector("#webview"); Map<String,String> map=new Map(); map["src"]=urlWebView; webview.attributes.addAll(map); webview.style.visibility="visible";

DartEditor version= STABLE build 45396

The version number of the SDK= 1.10.0

The webview loads a page that works on a js not created by me.

The error occurs when using this:



A webview cannot show those by default.

You need to catch the dialog event, show your own UI for it (remember, Apps can't use alert and friends, so a <dialog> is a good option) and then pass the response back with DialogController


more Clarification on @Xan Answer:

you need to listen to the dialog event from the webview ,Please read the comments in the code to understand better , again, I am using nwjs, so you can implement similar version in your language:

//lets listen to alert dom and enable it webview.addEventListener('dialog',function(e){ //message type messageType = e.messageType; messageText = e.messageText; DialogController = e.dialog; //lets checki if alert if(messageType == 'alert'){ window.alert(messageText); }//emd if //if confirm else if(messageType == 'confirm'){ //confirm var confirm = window.confirm(messageText); //get confirm bool and send to controller if(confirm == true){ //if true send okay to browser DialogController.ok(); }else{ //send cancel with to send false false DialogController.cancel(); }//end if }//end if confirm //lastly if its prompt else if(messageType == 'prompt'){ //get user Input promptInput = window.prompt(messageText); //if null , then means the user clicked cancel if(promptInput == null){ //tell browser to cancel DialogController.cancel(); }else{ //feed browser with input data DialogController.ok(promptInput); } }//end if prompt });//end dialog test


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