Android仿微信公众号文章页面加载进度条的实现方法

@SuppressWarnings("deprecation")
public class ProgressWebView extends WebView {

 private ProgressBar progressbar;

 public ProgressWebView(Context context) {
 super(context);
 init(context);
 }

 private void init(Context context) {
 progressbar = new ProgressBar(context, null,
  android.R.attr.progressBarStyleHorizontal);
 progressbar.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
  6, 0, 0));
 progressbar.setProgressDrawable(this.getResources().getDrawable(
  R.drawable.btn_progress_webview));
 addView(progressbar);
 setWebChromeClient(new WebChromeClient());
 }

 public ProgressWebView(Context context, AttributeSet attrs) {
 super(context, attrs);
 init(context);
 }

 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
 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);
 }
}

<&#63;xml version="1.0" encoding="UTF-8"&#63;>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >

 <!-- 设置背景色（黑色） -->
 <item android:id="@android:id/background">
 <shape>

  <!-- 进度条的四个棱角大小 0 为都是直角 随着值的增大角越圆滑 -->
  <corners android:radius="0dip" />

  <gradient
  android:endColor="#c0c0c0"
  android:startColor="#c0c0c0" />
 </shape>
 </item>

 <!-- 设置进度条颜色（绿色） -->
 <item android:id="@android:id/progress">
 <clip>
  <shape>
  <corners android:radius="0dip" />

  <gradient
   android:endColor="#a13864"
   android:startColor="#a13864" />
  </shape>
 </clip>
 </item>

</layer-list>

<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.summer.progresswebview.MainActivity" >

 <com.summer.progresswebview.ProgressWebView

 android:id="@+id/progresswebview"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent"/>

</RelativeLayout>

public class MainActivity extends Activity {
 private ProgressWebView progresswebview;

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

 private void initView() {
 progresswebview = (ProgressWebView) findViewById(R.id.progresswebview);
 progresswebview.getSettings()
  .setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
 progresswebview.getSettings().setJavaScriptEnabled(true);
 progresswebview.getSettings().setSupportZoom(true);
 progresswebview.getSettings().setLoadWithOverviewMode(true);
 progresswebview.getSettings().setUseWideViewPort(true);
 progresswebview.setVerticalScrollBarEnabled(false);
 progresswebview.setHorizontalScrollBarEnabled(false);// 水平不显示

 progresswebview.getSettings().setBuiltInZoomControls(true); // 支持页面放大缩小按钮
 progresswebview.setWebViewClient(client);
 progresswebview.loadUrl("https://www.baidu.com/"); // 加载百度首页网址
 }

private WebViewClient client = new WebViewClient() {

 @Override
 public void onPageFinished(WebView view, String url) {
  super.onPageFinished(view, url);
  progresswebview.getSettings().setLoadsImagesAutomatically(true);
 }

 @Override
 public void onPageStarted(WebView view, String url, Bitmap favicon) {
  super.onPageStarted(view, url, favicon);
 }


 public boolean shouldOverrideUrlLoading(WebView view, String url) {

  //调用拨号程序 
  if (url.startsWith("mailto:") || url.startsWith("geo:") ||url.startsWith("tel:")) { 
  Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url)); 
  startActivity(intent); 
  }else
  view.loadUrl(url);


  return true;
 }

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

 }

 };

}