我有一个WebView正在从互联网加载一个页面。我想显示一个ProgressBar,直到加载完成。

我如何监听WebView页面加载的完成?


当前回答

我把NeTeInStEiN的代码简化成这样:

mWebView.setWebViewClient(new WebViewClient() {
        private int       webViewPreviousState;
        private final int PAGE_STARTED    = 0x1;
        private final int PAGE_REDIRECTED = 0x2;

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String urlNewString) {
            webViewPreviousState = PAGE_REDIRECTED;
            mWebView.loadUrl(urlNewString);
            return true;
        }

        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            webViewPreviousState = PAGE_STARTED;
            if (dialog == null || !dialog.isShowing())
                dialog = ProgressDialog.show(WebViewActivity.this, "", getString(R.string.loadingMessege), true, true,
                        new OnCancelListener() {

                            @Override
                            public void onCancel(DialogInterface dialog) {
                                // do something
                            }
                        });
        }

        @Override
        public void onPageFinished(WebView view, String url) {

            if (webViewPreviousState == PAGE_STARTED) {
                dialog.dismiss();
                dialog = null;
            }

        }
 });

这很容易理解,OnPageFinished如果之前的回调是onpagstarted,所以页面是完全加载的。

其他回答

如果你想显示一个进度条,你需要监听一个进度变化事件,而不仅仅是页面的完成:

mWebView.setWebChromeClient(new WebChromeClient(){

            @Override
            public void onProgressChanged(WebView view, int newProgress) {

                //change your progress bar
            }


        });

顺便说一句,如果你只想显示一个覆盖onPageFinished方法的Indeterminate ProgressBar就足够了

我发现了一个优雅的解决方案,虽然没有严格测试:

public void onPageFinished(WebView view, String url) {
            super.onPageFinished(view, url);
            if (webView.getProgress() == 100) {
                progressBar.setVisibility(View.GONE);
                webView.setVisibility(View.VISIBLE);
            }
        } 

加载url与swiperfreshlayout和ProgressBar: UrlPageActivity.java:

    WebView webView;
    SwipeRefreshLayout _swipe_procesbar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_url_page);


        String url = "http://stackoverflow.com/";

        _swipe_procesbar = (SwipeRefreshLayout)findViewById(R.id.url_path_swipe_procesbar);

        _swipe_procesbar.post(new Runnable() {
                                  @Override
                                  public void run() {
                                      _swipe_procesbar.setRefreshing(true);
                                  }
                              }
        );

        webView = (WebView) findViewById(R.id.url_page_web_view);
        webView.getSettings().setJavaScriptEnabled(true);

        webView.setWebViewClient(new WebViewClient() {
            public void onPageFinished(WebView view, String url) {
                _swipe_procesbar.setRefreshing(false);
                _swipe_procesbar.setEnabled(false);
            }
        });
        webView.loadUrl(url);
    }

activity_url_page.xml:

<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/url_path_swipe_procesbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
        <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
            android:layout_height="match_parent"
            tools:context="com.test.test1.UrlPageActivity">


            <WebView
                android:layout_width="fill_parent"
                android:layout_height="fill_parent"
                android:id="@+id/url_page_web_view" />
        </RelativeLayout>

</android.support.v4.widget.SwipeRefreshLayout>

使用setWebViewClient()并重写onPageFinished()

用这个应该会有帮助。' var currentUrl = "google.com" var partOfUrl = currentUrl。currentUrl.length-2 substring (0)

webView.setWebViewClient(object: WebViewClient() {

override fun onLoadResource(WebView view, String url) {
     //call loadUrl() method  here 
     // also check if url contains partOfUrl, if not load it differently.
     if(url.contains(partOfUrl, true)) {
         //it should work if you reach inside this if scope.
     } else if(!(currentUrl.startWith("w", true))) {
         webView.loadurl("www.$currentUrl")

     } else if(!(currentUrl.startWith("h", true))) {
         webView.loadurl("https://$currentUrl")

     } else { ...}


 }

override fun onReceivedSslError(view: WebView?, handler: SslErrorHandler?, error: SslError?) {
   // you can call again loadUrl from here too if there is any error.
}

//你也应该覆盖其他覆盖错误的方法,如onReceiveError,以查看所有这些方法是如何一个接一个地被调用的,以及它们在调试断点时的行为。 } `