使用 webview 显示进度条

Question

**我正在开发一个带有webview的android应用程序。当内容加载到webview中时，我需要显示一个进度条。一旦内容加载完成，进度应该被关闭。对于webview部分，我使用下面的代码。我使用 thread.sleep 来 setJavaScriptEnabled(true)，因为我首先 setJavaScriptEnabled(false) 和 15 秒后 setJavaScriptEnabled(true)。我应该怎么做

public class Activity1 extends Activity {

private WebView webView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_activity1);
    Toast.makeText(getApplicationContext(), "welcome", Toast.LENGTH_LONG).show();
    String url = "http://student.iaun.ac.ir";
    webView = (WebView) findViewById(R.id.webview);

    webView.setWebViewClient(new myWebViewClient());
    webView.getSettings().setJavaScriptEnabled(false);
    webView.getSettings().setLoadWithOverviewMode(true);
    webView.getSettings().setUseWideViewPort(true);
    webView.getSettings().setBuiltInZoomControls(true);
    webView.loadUrl(url);
    webView.getSettings().setSavePassword(false);

    new Thread(new Runnable() {

        @Override
        public void run() {
            try {
                startDelay();
                webView.getSettings().setJavaScriptEnabled(true);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }).start();

}

void startDelay() throws InterruptedException {
    Thread.sleep(15000);
}

public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity1, menu);
    return true;

}

public boolean onKeyDown(int keyCode, KeyEvent event) {
    // Check if the key event was the Back button and if there's history
    if ((keyCode == KeyEvent.KEYCODE_BACK) && webView.canGoBack()) {
        webView.goBack();
        return true;
    }
    // If it wasn't the Back key or there's no web page history, bubble up to the default
    // system behavior (probably exit the activity)
    return super.onKeyDown(keyCode, event);
}
}

Answer 1

你可以用更简单的方式实现进度条

protected static ProgressBar progressBar;

//Some Codes
WebView loginwebview = (WebView) activity.findViewById(R.id.login_webview);
loginwebview.setWebChromeClient
    (
       new WebChromeClient()
       {
         @Override
          public void onProgressChanged(WebView view, int newProgress) 
           {
             activity.setTitle("Loading...Please wait");
             startSpinner();
             activity.setProgress(newProgress * 100);
             if(newProgress == 100)
               {
                    activity.setTitle(R.string.app_name);
                    stopSpinner();
               }
         }
      });

loginwebview.setWebViewClient(new WebViewClient() 
    {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) 
        {
           view.loadUrl(url);
           return true;

    }

还有 startSpinner() 和 stopSpinner() 方法

 protected static void startSpinner(){progressBar.setVisibility(WebView.VISIBLE);}
 protected static void stopSpinner(){progressBar.setVisibility(WebView.GONE);}

Answer 2

使用 Bellow 类希望它会起作用

public class myWebViewClient extends WebViewClient {
private ProgressDialog dialog;
private String redirect_str = "Processing...\nPlease wait...";
Context context;
public MyWebViewClient(Context context) {
    this.context = context;
}

@Override
public void onPageStarted(WebView paramWebView, String paramString, Bitmap paramBitmap) {
    super.onPageStarted(paramWebView, paramString, paramBitmap);
    if(this.dialog == null) {
        this.dialog = ProgressDialog.show(this.context, "", this.redirect_str, true);
    }
}


@Override
public void onPageFinished(WebView paramWebView, String paramString) {
    super.onPageFinished(paramWebView, paramString);
    if (this.dialog != null) {
        this.dialog.dismiss();
        this.dialog = null;
    }
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String paramString) {
    view.loadUrl(paramString);
    return true;
}
}

Answer 3

试试这个..

全球

ProgressDialog pDialog;

在java

里面

pDialog = ProgressDialog.show(Activity1.this, "Loading", "Please wait...", true);
webView.getSettings().setJavaScriptEnabled(false);
webView.getSettings().setLoadWithOverviewMode(true);
webView.getSettings().setUseWideViewPort(true);
webView.getSettings().setBuiltInZoomControls(true);

webview.setWebViewClient(new WebViewController());

WebViewController

public class WebViewController extends WebViewClient {

        @Override
           public boolean shouldOverrideUrlLoading(WebView view, String url) {
               view.loadUrl(url);
               view.getSettings().setSavePassword(false);
               return true;
           }

       public void onPageFinished(WebView view, String url) {

           if(pDialog != null)
           {
               if(pDialog.isShowing())
                   pDialog.dismiss();
               }
           }
   }

更多想法参考此link1,link2

Answer 4

//我使用了这个类，我的代码在我身边工作，请试试这个可能对你有帮助

public class WebViewActivity extends Activity {
    private WebView webview;
    private static final String TAG = "Main";
    private ProgressDialog progressBar;
    private TextView header_maintext;
    private TextView headeroptiontext;
    private RelativeLayout back;
    private String url_string="http://www.google.com";
    private String header_maintext_string="Your text";  

    /** Called when the activity is first created. */
    @SuppressLint("SetJavaScriptEnabled") @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
         requestWindowFeature(Window.FEATURE_NO_TITLE);
         setContentView(R.layout.webview_layout);


        webview = (WebView)findViewById(R.id.webview01);
        header_maintext= (TextView)findViewById(R.id.header_maintext);
        header_maintext.setText(header_maintext_string);

        headeroptiontext = (TextView)findViewById(R.id.headeroptiontext);
        headeroptiontext.setVisibility(View.GONE);

        WebSettings settings = webview.getSettings();
        settings.setJavaScriptEnabled(true);
        webview.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
        webview.getSettings().setLoadWithOverviewMode(true);
        webview.getSettings().setUseWideViewPort(true);

          back = (RelativeLayout) findViewById(R.id.back_layout);
          back.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) 
            {
                // TODO Auto-generated method stub
                if(webview.canGoBack() == true)
                    {
                        webview.goBack();
                    }
                else
                    {
                        finish();
                    }
             }
        });

        final AlertDialog alertDialog = new AlertDialog.Builder(this).create();

        progressBar = ProgressDialog.show(WebViewActivity.this, "My application", "Loading...");

        webview.setWebViewClient(new WebViewClient() {
            public boolean shouldOverrideUrlLoading(WebView view, String url) {

                view.loadUrl(url);
                return true;
            }

            public void onPageFinished(WebView view, String url) {
                Log.i(TAG, "Finished loading URL: " +url);
                if (progressBar.isShowing()) {
                    progressBar.dismiss();
                }
            }

            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {

                Toast.makeText(WebViewActivity.this, "Oh no! " + description, Toast.LENGTH_SHORT).show();
                alertDialog.setTitle("Error");
                alertDialog.setMessage(description);
                alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        return;
                    }
                });
                alertDialog.show();
            }
        });
        webview.loadUrl(url_string);


    }
    @Override

    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if(event.getAction() == KeyEvent.ACTION_DOWN){
            switch(keyCode)
            {
            case KeyEvent.KEYCODE_BACK:
                if(webview.canGoBack() == true){
                    webview.goBack();
                }else{
                    finish();
                }
                return true;
            }

        }
        return super.onKeyDown(keyCode, event);
    }
}