Question

这是一个从短网址获取长网址的功能，例如goo.gl，bit.ly ...

private String expandUrl(String shortUrl) {
    String finalURL = "";
    webView.loadUrl(shortUrl);
    webView.setWebViewClient(new WebViewClient() {
        public void onPageFinished(WebView view, String url) {
            finalURL = webView.getUrl();
        }
    });
    return finalURL;
}

我想将webView.getUrl()存储到字符串调用finalURL，以便我以后可以使用它，但它会出错

错误：从内部类中访问局部变量finalURL;需要被宣布为最终

我的错误是什么？

Answer 1

您正在匿名类中使用已定义的字段，如果您需要更改此字段，则将其设为类级变量。在所有方法之外声明它。试试这个

public String finalURL = "";

Answer 2

如果finalURL变量是外部类的成员变量，那么您可以将webView.getUrl（）保存到finalURL以用于以后的目的，例如解析但如果finalURL是局部变量，那么除非你是不可能的将它作为数组对象和最终变量。使用以下代码。而不是使用普通的finalURL，使用finalURL [0]来存储和解析。

final String[] finalURL = {""};
String url1 = "goo.gl/RvoAZH";
webView.loadUrl(url1);
webView.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url) {
System.out.println(webView.getUrl()); // whatever way to debug
finalURL[0] = webView.getUrl();
}
});

在下面的示例中，您可以看到局部变量localVar的值被来自＆＃34;＆＃34;的匿名对象内的方法（anonyMethod）更改。到了

public class Check {
    public void method() {
        final String[] localVar = {""};
        new Object() {
            public void anonyMethod() {
                System.out.println(localVar[0]); // sure
                localVar[0] = "a"; // nope
            }
        }.anonyMethod();
        System.out.println(localVar[0]);
    }

    public static void main(String[] args)
    {
        Check ck = new Check();
        ck.method();
    }
}

编辑1 您还可以发布更多代码。

编辑2 添加了我自己的示例代码。

Answer 3

你可以尝试这个

  private class MyWebViewClient extends WebViewClient {
        @SuppressWarnings("deprecation")
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            final Uri uri = Uri.parse(Uri.decode(url));
            return handleUri(uri);
        }

        @TargetApi(Build.VERSION_CODES.N)
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
            final Uri uri = request.getUrl();
            return handleUri(uri);
        }

        private boolean handleUri(final Uri uri) {
            return false;
        }

        @Override
        public void onLoadResource(WebView view, String url) {
            if (url.equals("http://yoururl.com")) {
                // do something
            }
        }

        @Override
        public void onFormResubmission(WebView view, Message dontResend, Message resend) {
            resend.sendToTarget();
        }

        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            mCacheWebView.setVisibility(View.INVISIBLE);
            showSwipeRefresh();
        }

        @Override
        public void onPageFinished(WebView view, String url) {
            super.onPageFinished(view, url);
            if (webViewError) {
                setErrorWebView();
            } else {
                if (mCacheWebView != null) {
                    mCacheWebView.loadUrl("javascript:(function() { " +
                            "var head = document.getElementsByTagName('header')[0];"
                            + "head.parentNode.removeChild(head);" +
                            "})()");
                    mCacheWebView.setVisibility(View.VISIBLE);
                }
            }
            hideSwipeRefresh();
        }

        @Override
        public void onReceivedHttpError(WebView view, WebResourceRequest request, WebResourceResponse errorResponse) {
            super.onReceivedHttpError(view, request, errorResponse);
        }

        @Override
        public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
            String message = "SSL Certificate error.";
            switch (error.getPrimaryError()) {
                case SslError.SSL_UNTRUSTED:
                    message = "The certificate authority is not trusted.";
                    break;
                case SslError.SSL_EXPIRED:
                    message = "The certificate has expired.";
                    break;
                case SslError.SSL_IDMISMATCH:
                    message = "The certificate Hostname mismatch.";
                    break;
                case SslError.SSL_NOTYETVALID:
                    message = "The certificate is not yet valid.";
                    break;
            }
            message += " Do you want to continue anyway?";
            Toast.makeText(mContext, message, Toast.LENGTH_SHORT).show();
        }

        @RequiresApi(api = Build.VERSION_CODES.M)
        @Override
        public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
            onReceivedError(view, error.getErrorCode(), error.getDescription().toString(), request.getUrl().toString());
//            view.loadUrl("file:///android_asset/no_internet.html");
        }

        @Override
        public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
            webViewError = true;

        }
    }

Android - 如何使用WebView扩展缩短的URL

3 个答案: