//加載本地資源
loadUrl("file:///android_asset/example.html");
//加載網(wǎng)絡(luò)資源
loadUrl("http://baidu.com");

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

  <item android:id="@android:id/progress">
    <clip>
      <shape>
        <solid android:color="#31CE15"/>
        <corners android:radius="2dp"/>
      </shape>
    </clip>
  </item>

</layer-list>

/**
 * 帶進(jìn)度條的WebView
 * @Author GQ
 */
public class ProgressWebView extends WebView {

  private ProgressBar progressbar;
  private Context mContext;

  public ProgressWebView(Context context, AttributeSet attrs) {
    super(context, attrs);
    this.mContext = context;
    progressbar = new ProgressBar(context, null, android.R.attr.progressBarStyleHorizontal);
    progressbar.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, 5, 0, 0));

    Drawable drawable = context.getResources().getDrawable(R.drawable.view_progress_webview);
    progressbar.setProgressDrawable(drawable);
    addView(progressbar);

    //主要處理解析，渲染網(wǎng)頁等瀏覽器做的事情
    setWebViewClient(new WebViewClient() {
      @Override
      public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
        super.onReceivedError(view, errorCode, description, failingUrl);
        //加載失敗時(shí)候,顯示自定義的頁面
        if (errorListener != null) {
          errorListener.onError();
        }
      }
    });
    //輔助WebView處理Javascript的對話框，網(wǎng)站圖標(biāo)，網(wǎng)站title，加載進(jìn)度等
    setWebChromeClient(new WebChromeClient());

    getSettings().setSupportZoom(true);//是否可以縮放
    getSettings().setBuiltInZoomControls(true);
    getSettings().setJavaScriptEnabled(true);//支持JS
    getSettings().setLayoutAlgorithm(WebSettings.LayoutAlgorithm.NARROW_COLUMNS);
    getSettings().setUseWideViewPort(true);
    getSettings().setLoadWithOverviewMode(true);
    getSettings().setSaveFormData(true);
    getSettings().setDomStorageEnabled(true);

    //優(yōu)先使用緩存
    getSettings().setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);

    //禁用長按
    setOnLongClickListener(new OnLongClickListener() {
      @Override
      public boolean onLongClick(View view) {
        return true;
      }
    });

    //如果在瀏覽器下載,調(diào)用瀏覽器默認(rèn)下載+通知欄
    setDownloadListener(new DownloadListener() {
      @Override
      public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimetype, long contentLength) {
        Uri uri = Uri.parse(url);
        Intent intent = new Intent(Intent.ACTION_VIEW, uri);
        mContext.startActivity(intent);
      }
    });
  }


  public class WebChromeClient extends android.webkit.WebChromeClient {
    @Override
    public void onProgressChanged(WebView view, int newProgress) {
      if (newProgress == 100) {
        progressbar.setVisibility(GONE);
      } else {
        if (progressbar.getVisibility() == GONE)
          progressbar.setVisibility(VISIBLE);
        progressbar.setProgress(newProgress);
      }
      super.onProgressChanged(view, newProgress);
    }

    @Override
    public void onReceivedTitle(WebView view, String title) {
      super.onReceivedTitle(view, title);
      if (titleListener != null)
        titleListener.getTitle(title);
    }

  }


  @Override
  protected void onScrollChanged(int l, int t, int oldl, int oldt) {
    LayoutParams lp = (LayoutParams) progressbar.getLayoutParams();
    lp.x = l;
    lp.y = t;
    progressbar.setLayoutParams(lp);
    super.onScrollChanged(l, t, oldl, oldt);
  }

  private TitleListener titleListener;

  public interface TitleListener {
    void getTitle(String title);
  }

  public void setOnTitleListener(TitleListener titleListener) {
    this.titleListener = titleListener;
  }

  private ErrorListener errorListener;

  public interface ErrorListener {
    void onError();
  }

  public void setOnErrorListener(ErrorListener errorListener) {
    this.errorListener = errorListener;
  }

}

/**
* 公共WebView
*/
public class BasicWebActivity extends Activity {

  protected ProgressWebView progressWebView;
  private TextView title;//標(biāo)題欄
  private TextView tv_none;//加載失敗顯示文字

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

    title = (TextView) findViewById(R.id.title);
    tv_none = (TextView) findViewById(R.id.tv_none);
    progressWebView = (ProgressWebView) findViewById(R.id.progressWebView);

    String url = getIntent().getStringExtra("url");
    progressWebView.setOnTitleListener(new ProgressWebView.TitleListener() {
      @Override
      public void getTitle(String title) {
        title.setText(title);
      }
    });
    progressWebView.setOnErrorListener(new ProgressWebView.ErrorListener() {
      @Override
      public void onError() {
        tv_none.setText("url資源失效");
      }
    });
    //加載網(wǎng)頁
    progressWebView.loadUrl(url);
  }

 //重寫返回鍵
  @Override
  public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
      if (progressWebView.canGoBack()) {
        progressWebView.goBack();//返回上一層頁面
        return true;
      } else {
        finish();//關(guān)閉頁面
      }
    }
    return super.onKeyDown(keyCode, event);
  }
}