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();    }  }}