Android在调用API的WebView中调用JavaScript函数<= 18
问题描述:
这个问题在这里并不新鲜,但我仍然无法得到它出错的地方。我只是想评估一些JavaScript。Android在调用API的WebView中调用JavaScript函数<= 18
我简单的代码看起来像:
WebView wv = new WebView(context);
WebSettings settings = wv.getSettings();
settings.setJavaScriptEnabled(true);
JavaBridgeToJS bridgeToJS = new JavaBridgeToJS();
wv.addJavascriptInterface(bridgeToJS, "javaCallback");
String src = "javascript: var result= 3 + 3; window.javaCallback.resultOfAdd(result)";
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
Log.d(TAG, "Newer than JellyBean.");
ValueCallback<String> result = new ValueCallback<String>() {
@Override
public void onReceiveValue(String value) {
Log.d(TAG, "Got in onReceiveValue: " + value);
}
};
wv.evaluateJavascript(src, result);
}else {
Log.d(TAG, "Older than Kitkat");
wv.loadUrl(src);
}
和
public class JavaBridgeToJS {
@JavascriptInterface
public void resultOfAdd(String result) {
Log.d(TAG, "Here is: " + result);
}
}
这是工作好API 19+,即使没有如果用的版本检查(我的意思是与loadUrl以及评估JavaScript一起工作)
但是当我尝试API 18,不调用java中的回调。 我已到目前为止,我有没有运气环顾四周(remove line break,或quotes missing(可能受感染,看着手机上),等等...)
。任何想法?
编辑
好吧,我加入的代码在办案JS里面的错误,我已经错过了什么。
wv.setWebChromeClient(new CustomWebChromeClient());
为
public class CustomWebChromeClient extends WebChromeClient {
private CustomWebChromeClient() {
super();
}
@Override
public boolean onConsoleMessage(ConsoleMessage consoleMessage) {
UILog.d(TAG, consoleMessage.message());
return super.onConsoleMessage(consoleMessage);
}
}
,我和他惊讶:
E/dalvikvm: Could not find class 'android.webkit.PermissionRequest', referenced from method com.example.WebViewDoll$CustomWebChromeClient.access$super
VFY: unable to resolve check-cast 1896 (Landroid/webkit/PermissionRequest;) in Lcom/example/WebViewDoll$CustomWebChromeClient;
E/dalvikvm: Could not find class 'android.webkit.WebChromeClient$FileChooserParams', referenced from method com.example.WebViewDoll$CustomWebChromeClient.access$super
VFY: unable to resolve check-cast 1899 (Landroid/webkit/WebChromeClient$FileChooserParams;) in Lcom/example/WebViewDoll$CustomWebChromeClient;
E/dalvikvm: Could not find class 'android.webkit.PermissionRequest', referenced from method com.example.WebViewDoll$CustomWebChromeClient.access$super
D/WebViewDoll: Uncaught TypeError: Cannot call method 'resultOfAdd' of undefined
E/Web Console: Uncaught TypeError: Cannot call method 'resultOfAdd' of undefined at null:1
答
我没有找到一个答案,为什么这是行不通的,但与此using js in webview的帮助下,我才得以解决方法...
我必须注入我的js到html页面。所以,我的包装以防万一JS的样子:和
String src = "<html><head><script type=\"text/javascript\">" +
"function myFunction()" +
"{" +
" javaCallback.resultOfAdd(3+3);" +
"}" +
"</script></head><body onload=\"myFunction()\"/>" +
"</html>";
代替wv.loadUrl我用:
wv.loadData(src, "text/html", "UTF-8");
这种组合具有相同的结果需要。
**更新**我做了新的项目,以防万一,但仍然没有。 我想这应该工作[github回购](https://github.com/ThinkDeeper/webview_api18) – ThinkDeep