


How Can I Successfully Call JavaScript Functions from an Android WebView?
Nov 25, 2024 am 08:21 AMCalling JavaScript Functions from WebView in Android
When integrating HTML pages within an Android WebView, you may encounter situations where you need to call JavaScript functions residing within the page. This can be achieved by registering a Java class to expose methods to JavaScript and using JavaScriptInterface in the WebView's initialization. However, if you're experiencing difficulties with this process, there may be a couple of reasons.
One common issue is omitting quotes in the JavaScript function's parameter. Ensure that you enclose the message within quotes, as seen in this corrected code:
myWebView.loadUrl("javascript:testEcho('Hello World!')");
Another possible problem could stem from external JavaScript files referenced in the HTML. These external scripts may interfere with the communication between your Java class and the JavaScript function. Check if removing or disabling these external files resolves the issue.
If you've taken care of these two areas and your problem persists, consider reviewing the following aspects:
- Make sure the JavaScript function is defined in the correct file and accessible within the HTML page.
- Check if the Java class is properly registered with the WebView and contains the appropriate methods with correct parameters.
- Verify that the WebView has JavaScript enabled and is correctly initialized with the Java class.
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