WebView: Uncaught ReferenceError: Android is not defined
WebView: Uncaught ReferenceError: Android is not defined
我正在使用代码创建 WebView，而不是通过 XML 布局加载。网络视图似乎已正确创建，但我看到了错误：
W/AwContents( 4564): nativeOnDraw failed; clearing to background color.
I/chromium( 4564): [INFO:CONSOLE(1)] "Uncaught ReferenceError: Android is not defined",
...
如果我将 WebView 放在我的 XML 布局中，我不会收到这些错误。请注意，如果脚本运行，它会将 onLoadEvent 字段值从 "no" 更改为 "yes. That is happening, so evidently the script is running. It is not fetching the user name and password, though, indicating that "Android" is not defined.
我也试过在 webView.loadData() 之前执行 addView()；同样的错误。
下面是创建 WebView 的代码：
@SuppressLint("SetJavaScriptEnabled")
private void onOk ()
{
Log.d ("RegTest", "onOk");
webView = new WebView (this);
webView.setLayoutParams (new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT));
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled (true);
CharSequence cs = readAsset ("input_form");
webView.loadData (cs.toString(), "text/html", "UTF-8");
contentView.addView (webView);
}
这里是 "input_form" 的片段，这是 WebView 内容的来源：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
...
<script type="text/javascript">
function onLoadValues ()
{
document.getElementById ("onLoadEvent").value = "yes";
document.getElementById ("FullName").value = Android.getFullName();
document.getElementById ("EmailAddress").value = Android.getEmailAddr();
}
</script>
</head>
<body onload="onLoadValues()">
<form name="catwebformform52174" method="post" ...>
<fieldset>
<div class="pure-control-group">
<label for="onLoadValues">onLoadEvent</label>
<input id="onLoadEvent" name="onLoadEvent" type="text" placeholder="no">
</div>
<div class="pure-control-group">
<label for="FullName">Name</label>
<input id="FullName" name="FullName" type="text" placeholder="Name">
</div>
<div class="pure-control-group">
<label for="EmailAddress">Email Address</label>
<input id="EmailAddress" name="EmailAddress" type="email" placeholder="Email Address">
</div>
</fieldset>
</form>
</body>
</html>
您没有将 Android 定义为 javascripinterface 您必须在下面的行中写
// If your callback methods are in same class then just same class object
webView.addJavascriptInterface(this, "Android");
addJavascriptInterface() 方法的语法
addJavascriptInterface(Object object, String name);
// 1. `object` – *the Java object to inject into this WebView’s JavaScript context.*
// 2. `name` – *the name used to expose the object in JavaScript*
如果您来到这里是因为您只是在浏览文档，他们会遗漏一条关键信息，该信息仅在 addJavascriptInterface() 的参考文档中可用。
Note that injected objects will not appear in JavaScript until the page is next (re)loaded. JavaScript should be enabled before injecting the object. For example:
class JsObject {
@JavascriptInterface
public String toString() { return "injectedObject"; }
}
webview.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(new JsObject(), "injectedObject");
webView.loadData("", "text/html", null);
webView.loadUrl("javascript:alert(injectedObject.toString())");
我正在使用代码创建 WebView，而不是通过 XML 布局加载。网络视图似乎已正确创建，但我看到了错误：
W/AwContents( 4564): nativeOnDraw failed; clearing to background color.
I/chromium( 4564): [INFO:CONSOLE(1)] "Uncaught ReferenceError: Android is not defined",
...
如果我将 WebView 放在我的 XML 布局中，我不会收到这些错误。请注意，如果脚本运行，它会将 onLoadEvent 字段值从 "no" 更改为 "yes. That is happening, so evidently the script is running. It is not fetching the user name and password, though, indicating that "Android" is not defined.
我也试过在 webView.loadData() 之前执行 addView()；同样的错误。
下面是创建 WebView 的代码：
@SuppressLint("SetJavaScriptEnabled")
private void onOk ()
{
Log.d ("RegTest", "onOk");
webView = new WebView (this);
webView.setLayoutParams (new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT));
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled (true);
CharSequence cs = readAsset ("input_form");
webView.loadData (cs.toString(), "text/html", "UTF-8");
contentView.addView (webView);
}
这里是 "input_form" 的片段，这是 WebView 内容的来源：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
...
<script type="text/javascript">
function onLoadValues ()
{
document.getElementById ("onLoadEvent").value = "yes";
document.getElementById ("FullName").value = Android.getFullName();
document.getElementById ("EmailAddress").value = Android.getEmailAddr();
}
</script>
</head>
<body onload="onLoadValues()">
<form name="catwebformform52174" method="post" ...>
<fieldset>
<div class="pure-control-group">
<label for="onLoadValues">onLoadEvent</label>
<input id="onLoadEvent" name="onLoadEvent" type="text" placeholder="no">
</div>
<div class="pure-control-group">
<label for="FullName">Name</label>
<input id="FullName" name="FullName" type="text" placeholder="Name">
</div>
<div class="pure-control-group">
<label for="EmailAddress">Email Address</label>
<input id="EmailAddress" name="EmailAddress" type="email" placeholder="Email Address">
</div>
</fieldset>
</form>
</body>
</html>
您没有将 Android 定义为 javascripinterface 您必须在下面的行中写
// If your callback methods are in same class then just same class object
webView.addJavascriptInterface(this, "Android");
addJavascriptInterface() 方法的语法
addJavascriptInterface(Object object, String name);
// 1. `object` – *the Java object to inject into this WebView’s JavaScript context.*
// 2. `name` – *the name used to expose the object in JavaScript*
如果您来到这里是因为您只是在浏览文档，他们会遗漏一条关键信息，该信息仅在 addJavascriptInterface() 的参考文档中可用。
Note that injected objects will not appear in JavaScript until the page is next (re)loaded. JavaScript should be enabled before injecting the object. For example:
class JsObject {
@JavascriptInterface
public String toString() { return "injectedObject"; }
}
webview.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(new JsObject(), "injectedObject");
webView.loadData("", "text/html", null);
webView.loadUrl("javascript:alert(injectedObject.toString())");