Android中WebView加载网页设置进度条

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <LinearLayout  android:layout_width="match_parent"  android:layout_height="wrap_content">  <RelativeLayout   android:layout_width="match_parent"   android:layout_height="48dp"   android:background="@color/colorPrimary"   android:layout_weight="0">   <ImageView    android:id="@+id/activity_add_authentication_back"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:src="@drawable/activity_news_back"    android:layout_marginLeft="10dp"/>   <TextView    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="网页"    android:textColor="@color/white"    android:layout_centerVertical="true"    android:layout_centerHorizontal="true"    android:textSize="18sp"/>  </RelativeLayout> </LinearLayout> <ProgressBar  android:id="@+id/progressBar1"  style="?android:attr/progressBarStyleHorizontal"  android:layout_width="match_parent"  android:layout_height="3dip"  android:progressDrawable="@drawable/pg"  android:visibility="gone" /> <WebView  android:id="@+id/web_view"  android:layout_width="match_parent"  android:layout_height="match_parent"> </WebView></LinearLayout>

<layer-list xmlns:android="http://schemas.android.com/apk/res/android" > <item android:id="@android:id/background">  <shape>   <corners android:radius="2dp" />   <gradient    android:angle="270"    android:centerColor="#E3E3E3"    android:endColor="#E6E6E6"    android:startColor="#C8C8C8" />  </shape> </item> <item android:id="@android:id/progress">  <clip>   <shape>    <corners android:radius="2dp" />    <gradient     android:centerColor="#4AEA2F"     android:endColor="#31CE15"     android:startColor="#5FEC46" />   </shape>  </clip> </item></layer-list>

package com.vimi8.app.activity;import android.content.Context;import android.os.Bundle;import android.view.KeyEvent;import android.view.View;import android.webkit.JavascriptInterface;import android.webkit.WebChromeClient;import android.webkit.WebSettings;import android.webkit.WebView;import android.webkit.WebViewClient;import android.widget.ProgressBar;import android.widget.Toast;import com.vimi8.app.R;import com.vimi8.app.framework.ActivityBase;/** * Created by vimi8 on 2017/4/18. */public class YyxText extends ActivityBase { private WebView myWebView ; private ProgressBar pg1; @Override protected void initVariables(Bundle savedInstanceState) { } @Override protected int initLayoutViews() {  return R.layout.yyx_text; } @Override protected void initViewsAndStaticData() {  //获取webview控件  myWebView = (WebView) findViewById(R.id.web_view);  pg1=(ProgressBar) findViewById(R.id.progressBar1);  //加载服务器上的页面  myWebView.loadUrl("http://www.baidu.com");  //加载本地中的html  //myWebView.loadUrl("file:///android_asset/www/test2.html");  //加上下面这段代码可以使网页中的链接不以浏览器的方式打开  myWebView.setWebViewClient(new WebViewClient());  //得到webview设置  WebSettings webSettings = myWebView.getSettings();  //允许使用javascript  webSettings.setJavaScriptEnabled(true);  //将WebAppInterface于javascript绑定  myWebView.addJavascriptInterface(new WebAppInterface(this), "Android");  //设置经度条  myWebView.setWebChromeClient(new WebChromeClient(){   @Override   public void onProgressChanged(WebView view, int newProgress) {    // TODO 自动生成的方法存根    if(newProgress==100){     pg1.setVisibility(View.GONE);//加载完网页进度条消失    }    else{     pg1.setVisibility(View.VISIBLE);//开始加载网页时显示进度条     pg1.setProgress(newProgress);//设置进度值    }   }  }); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) {  if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {   myWebView.goBack();   return true;  }  return super.onKeyDown(keyCode, event); } public class WebAppInterface {  Context mContext;  /** Instantiate the interface and set the context */  WebAppInterface(Context c) {   mContext = c;  }  /** Show a toast from the web page */  @JavascriptInterface  public void showToast(String toast) {   Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();  } }}