android - 如何快速加载 WebView 并为其添加进度条

Question

我正在制作一个简单的应用程序，我在其中放置了一个 webview，但是页面加载速度非常慢(尝试过许多网站)，而且我想添加一个进度条，以便它应该显示页面正在加载。 这是我用于 webview 的代码，但我不知道如何在其上获取进度条:

public class MainActivity extends Activity {

WebView wv;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    wv = (WebView) findViewById(R.id.webView1);
    wv.setWebViewClient(new webCont());

    wv.loadUrl(" http://www.abc.com" ); 
}
 class webCont extends WebViewClient
{

    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        // TODO Auto-generated method stub
        view.loadUrl(url);

        return true;
    }
}

Answer 1

有一个进度条。显示一样。您可以自定义以下内容以满足您的需求。加载速度更快取决于连接速度。

覆盖 onPageFinished 并将可见性设置为 gone in webcount

public class MainActivity extends Activity {
    /** Called when the activity is first created. */

    WebView web;
    ProgressBar progressBar;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        web = (WebView) findViewById(R.id.wv);
        progressBar = (ProgressBar) findViewById(R.id.progressBar);
        web.setWebViewClient(new myWebClient());
        web.getSettings().setJavaScriptEnabled(true);
        web.loadUrl("http://slashdot.org/");
    }

    public class myWebClient extends WebViewClient
    {
        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            // TODO Auto-generated method stub
            super.onPageStarted(view, url, favicon);
        }

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            // TODO Auto-generated method stub

            view.loadUrl(url);
            return true;

        }
        @Override
        public void onReceivedError(WebView view, int errorCode,
                String description, String failingUrl) {
            // TODO Auto-generated method stub
             Toast.makeText(MainActivity.this, "Oh no! " + description, Toast.LENGTH_SHORT).show();
            //super.onReceivedError(view, errorCode, description, failingUrl);
        }
        @Override
        public void onPageFinished(WebView view, String url) {
            // TODO Auto-generated method stub
            super.onPageFinished(view, url);

            progressBar.setVisibility(View.GONE);
        }
    }

    // To handle "Back" key press event for WebView to go back to previous screen.
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) 
    {
        if ((keyCode == KeyEvent.KEYCODE_BACK) && web.canGoBack()) {
            web.goBack();
            return true;
        }
        else
        {
            finish();
            return true;
        }
    }
}

xml

 <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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <WebView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_above="@+id/button1"
        android:id="@+id/wv"/>
    <ProgressBar
       android:id="@+id/progressBar"
       android:layout_width="wrap_content"
       android:layout_centerInParent="true"
       android:layout_height="wrap_content"
       />


</RelativeLayout>

快照

不滚动你看不到整个页面

向右滚动