java - Android - 从Webview拦截链接

Question

所以我需要用户在 webview 中单击链接，在本例中它是包含 .pdf 文件的链接。我有启动 PDF 阅读器的代码，但它没有获取链接，因此它只是在单击 PDF 文件时加载 PDF 阅读器。如何拦截此链接并将其提供给我的 PDF 阅读器 Intent ？

代码:

public class atcFaa extends Activity {
WebView webview;
private String url;
ProgressBar pd = null;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.atccti);

    pd = (ProgressBar) findViewById(R.id.web_view_progress_bar);

    webview = (WebView) findViewById(R.id.ctiWebView);
    webview.getSettings().setJavaScriptEnabled(true);

    Button openPdfBtn = new Button(this);
    webview.addJavascriptInterface(openPdfBtn, "openPdfBtn");
    openPdfBtn.setOnClickListener(new OnClickListener() {

        public void onClick(View v) {
            openPdf();
        }
    });

    webview.setWebChromeClient(new WebChromeClient() {
        public void onProgressChanged(WebView view, int progress) {
            if (progress < 100 && pd.getVisibility() == ProgressBar.GONE) {
                pd.setVisibility(ProgressBar.VISIBLE);
            }
            pd.setProgress(progress);
            if (progress == 100) {
                pd.setVisibility(ProgressBar.GONE);
            }
        }
    });

    webview.setWebViewClient(new WebViewClient() {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            webview.getSettings().setJavaScriptEnabled(true);
            // do your handling codes here, which url is the requested url
            // probably you need to open that url rather than redirect:
            if (url.startsWith("tel:")) {
                startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
            } else if (url.startsWith("mailto:")) {
                url = url.replaceFirst("mailto:", "");
                url = url.trim();
                Intent i = new Intent(Intent.ACTION_SEND);
                i.setType("plain/text").putExtra(Intent.EXTRA_EMAIL,
                        new String[] { url });
                startActivity(i);

            } else if (url.startsWith("geo:")) {
                try {
                } catch (Exception e) {
                    System.out.println(e);
                }

            } else if (url.endsWith("pdf")) {
                try {

                }

                catch (ActivityNotFoundException e) {
                    Toast.makeText(atcFaa.this, "No PDF Viewer Installed",
                            Toast.LENGTH_LONG).show();
                }
            }

            else {
                view.loadUrl(url);
            }
            return true;
            // then it is not handled by default action
        }

    });

    webview.loadUrl("http://www.faa.gov/air_traffic/publications/");
}

protected void openPdf() {
    // TODO Auto-generated method stub
    Intent intent = new Intent();
    intent.setAction(Intent.ACTION_VIEW);
    Uri uri = Uri.parse(url);
    intent.setDataAndType(uri, "application/pdf");
    startActivity(intent);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu2, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
    case R.id.atcAbout2:
        Toast.makeText(this, "You pressed the icon!", Toast.LENGTH_LONG)
                .show();
        break;
    case R.id.atcContact2:
        emailme();
        break;

    }
    return true;
}

private void emailme() {
    // TODO Auto-generated method stub
    String domsEmail = "MYEMAIL@EXAMPLE.com";
    String message = "Insert Message Here";
    String myemail[] = { domsEmail };
    Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);
    emailIntent.putExtra(android.content.Intent.EXTRA_EMAIL, myemail);
    emailIntent.putExtra(android.content.Intent.EXTRA_SUBJECT,
            "ATC Assistant");
    emailIntent.setType("plain/text");
    emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, message);
    startActivity(emailIntent);
}

/*
 * @Override public void onBackPressed() { if (webview.canGoBack())
 * webview.goBack(); else super.onBackPressed(); }
 */

public void setUrl(String url) {
    this.url = url;
}

public String getUrl() {
    return url;
}
}

Answer 1

我不知道你的html代码的结构，但我会假装你有一个按钮。这是您的 html 中的代码:

<button onclick='openPdfBtn.performClick();'>Open pdf</button> 

然后添加一个js接口(interface)到你的webview中:

Button openPdfBtn = new Button(this); //this is not gonna be visible
yourWebView.addJavascriptInterface(openPdfBtn, "openPdfBtn"); //here you bind the js with the native button
openPdfBtn.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        openPdf();
    }
});