Exist stringByEvaluatingJavaScriptFromString for Android
Exist stringByEvaluatingJavaScriptFromString method in Android like Iphone?. Not with a simple code like this javascript:wave(). But with a complex Java S开发者_JS百科cript function. Thanks
You can use loadUrl
instead,eg:
webView.loadUrl("javascript:PerformSimpleCalculation()");
It's effect similar to stringByEvaluatingJavaScriptFromString
.The API description is not clear.
stringByEvaluatingJavaScriptFromString is a private method in Android API. But it is really useful.
You could retrive this API via Java reflection:
Method stringByEvaluatingJavaScriptFromString , sendMessageMethod;;
Object webViewCore , browserFrame;
private boolean hasIntercepted = true;
Object webViewObject = this;
Class webViewClass = WebView.class;
try {
Field mp = webViewClass.getDeclaredField("mProvider");
mp.setAccessible(true);
webViewObject = mp.get(this);
webViewClass = webViewObject.getClass();
Field wc = webViewClass.getDeclaredField("mWebViewCore");
wc.setAccessible(true);
webViewCore = wc.get(webViewObject);
if (webViewCore != null) {
sendMessageMethod = webViewCore.getClass().getDeclaredMethod("sendMessage", Message.class);
sendMessageMethod.setAccessible(true);
Field bf= webViewCore.getClass().getDeclaredField("mBrowserFrame");
bf.setAccessible(true);
browserFrame = bf.get(webViewCore);
stringByEvaluatingJavaScriptFromString = browserFrame.getClass().getDeclaredMethod("stringByEvaluatingJavaScriptFromString", String.class);
stringByEvaluatingJavaScriptFromString.setAccessible(true);
}
hasIntercepted = true;
} catch (Throwable e) {
hasIntercepted = false;
}
Then to use this method:
Object argument =(Object) ((String)"window.hitTest("+event.getX()+ ","+event.getY()+")");
try {
Object _tagName = stringByEvaluatingJavaScriptFromString.invoke(browserFrame, argument);
String tagName =(String)_tagName;
} catch (Exception e) {
e.printStackTrace();
}
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