如何为 android webview 实现 @JavascriptInterface

Question

Currently, my code is not giving normal output. Why is this so?

Android:

@JavascriptInterface
fun call(obj:JSONObject?){
    Log.i("webview","$obj")
}

output on Logcat

I: webview, null

js:

function callAndroid(obj) {
                    androidObj.call(obj);              
            }

callAndroid({
                    key_string: 'test'
                })

it is implemented add androidObj to webview,that is successful

Android:
@JavascriptInterface
fun call(str:String?)

js:
androidObj.call('hello')

but parameter use JSONObject is failed

Answer 1

There are 3 steps to create JavaScript interface for Android WebView.

First, Create the Javascript interface:

@JavascriptInterface
fun call(obj:JSONObject?){
    Log.i("webview","$obj")
}

Second, Add Javascript interface to your WebView and enable Javascript:

 webView.getSettings().setJavaScriptEnabled(true
 webView.addJavascriptInterface(this, "androidObj")

Now call the function from your JS:

androidObj.call(obj) 

Check if you have missed any of the above steps.