android 嵌入服务端页面二 之WebView与页面互调

WebView引入页面及回调处理

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:background="@color/white"
  android:orientation="vertical"
  >
  	<!-- 头部和尾部为重用和统一风格 -->
    <!-- 头部  -->
	<include layout="@layout/jx_two_page_header"/>
	<WebView
	    android:id="@+id/wvTicketOne"
	    android:layout_width="fill_parent"
	    android:layout_height="fill_parent" 
	    />    
    
	<!-- 尾部 -->
	<include android:id="@+id/footer" layout="@layout/jx_two_footer"/>
</LinearLayout>

 在Activity的onCreate方法中加载页面

@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.ticket_one);

		/**
		 * 在android 2.3以后进行了较为严格的限制
		 * 该类可以用来帮助开发者改进他们编写的应用。
		 * 并且提供了各种的策略，
		 * 这些策略能随时检查和报告开发者开发应用中存在的问题
		 */
		StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
				.detectDiskReads().detectDiskWrites().detectNetwork() 
				.penaltyLog().build());
		StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder()
				.detectLeakedSqlLiteObjects().penaltyLog().penaltyDeath()
				.build());		

		Intent fromInent = getIntent();
		ticketId = fromInent.getStringExtra("ticketId");
		//是否管理员
		String isManage = mPreferences.getString(Constants.USER_IS_MANAGE, String.valueOf(false));
		
		//找到WebView控件
		wvTicketOne = (WebView) findViewById(R.id.wvTicketOne);
		//设置为可访问页面JS，在Activity和页面直接互调时使用
		wvTicketOne.getSettings().setJavaScriptEnabled(true);
		
		wvTicketOne.setWebViewClient(new WebViewClient());		
		//在onCreate 方法中调用WebView的loadUrl方法加载页面内容
		wvTicketOne.loadUrl(Constants.URL_TICKET_ONE + ticketId+"&isManage="+isManage);
		//添加页面可访问的JS接口
		wvTicketOne.addJavascriptInterface(new JavaScriptInterface(), "android");
		
		// Activity间跳转：转到踏勘单
		TextView takandan = (TextView) findViewById(R.id.tanKanDan);
		takandan.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				Intent intent = new Intent(TicketOneActivity.this,TicketTanKanDan.class);
				intent.putExtra("ticketId", ticketId);
				startActivity(intent);
			}
		});
		
		//返回按钮：这里做了最简单的处理，直接把当前Activity给关掉，
		//程序自动返回到上一个Activity（前提是上一个Activity没有销毁）
		ImageButton btnBack = (ImageButton) findViewById(R.id.cursor_back);
		btnBack.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				finish();
			}
		});
		
		//隐藏(后退、1/1、前进、刷新)按钮
		ImageButton cursor_left = (ImageButton) findViewById(R.id.cursor_left);
		cursor_left.setVisibility(View.INVISIBLE);
		ImageButton cursor_right = (ImageButton) findViewById(R.id.cursor_right);
		cursor_right.setVisibility(View.INVISIBLE);
		ImageButton cursor_refresh = (ImageButton) findViewById(R.id.cursor_refresh);
		cursor_refresh.setVisibility(View.INVISIBLE);
		TextView tv_infoTotal=(TextView)findViewById(R.id.infoTotal);
		tv_infoTotal.setVisibility(View.INVISIBLE);
		TextView tv_infoView=(TextView)findViewById(R.id.infoView);
		tv_infoView.setVisibility(View.INVISIBLE);
		TextView tv_infoNum=(TextView)findViewById(R.id.infoNum);
		tv_infoNum.setVisibility(View.INVISIBLE);
	}

 

在Activity中创建一个页面可访问的JavaScript接口，供页面调用

 

private class JavaScriptInterface {
		
		private MediaPlayer mediaPlayer;
		
		public JavaScriptInterface(){
			mediaPlayer = new MediaPlayer();
		}
		
		/**
		 * 播放 
		 * @param url 播放文件路径
		 */
		public void playMusic(String url){
			if(mediaPlayer.isPlaying()){
				mediaPlayer.reset();
			}
			try{
				mediaPlayer.setDataSource(url);
				mediaPlayer.prepare();
				mediaPlayer.start();
			}catch (Exception e) {
				e.printStackTrace();
			}
		}
		
		/**
		 * 暂停 
		 */
		public void stopMusic(){
			if(mediaPlayer.isPlaying()){
				mediaPlayer.stop();
			}
		}	
		
		/**
		 * GPS显示
		 * @param gps
		 */
		public void showGps(String gps){
			Intent i = new Intent(TicketOneActivity.this, MapActivity.class);
			i.putExtra("gps", gps);
			startActivity(i);
		}
		
		/**
		 * 提示信息
		 * @param msg
		 */
		public void showMsg(String msg){
			if(CommonUtils.validateStr(msg)){
				Toast.makeText(TicketOneActivity.this, msg, Toast.LENGTH_SHORT).show();
			}
			if(CommonUtils.matchString(msg, "提交成功")){
				finish();
			}
		}
	}

 

上面的showMsg方法在页面被调用

	//页面调用Activity中的JavaScriptInterface方法
 	function Msg(msg){
 		if (window.android){
	      	window.android.showMsg(msg);
	   	}else{
			alert(msg);
	   	}
 	}

 ----------------------------------------------

 

在Activity中，也可以将处理的结果返回给页面。以下是一个在任务监听中将结果返回给页面JS的例子。

/**
	 * 签名任务监听
	 * 
	 * @author lihua
	 */
	private TaskListener signTicketTaskListener = new TaskAdapter() {

		@Override
		public void onPostExecute(GenericTask task, String result) {
			
			//处理完成删除本地文件
			FileHelper.delFiles(REC_DIR);
			
			JSONObject signInfo = (JSONObject) getApi().getBackResult(result,
					getApplicationContext());
			
			String data = "";
			String signdate = "";
			try {
				data = signInfo.getString("result");
				signdate = signInfo.getString("signdate");
				
			} catch (JSONException e) {
				e.printStackTrace();
			}
				
			String [] signArray = CommonUtils.splitByTag(data, "$");
			String words = "",sign ="",gps="",voice="",gid = "",gdt="";
			//add edit
			if(signArray!=null&&signArray.length>0)
				for (String s : signArray) {
					if(s!=null&&s.startsWith(Constants.START_TAG_WORD))
						words = s.replace(Constants.START_TAG_WORD, "");
					if(s!=null&&s.startsWith(Constants.START_TAG_SIGN))
						sign = s.replace(Constants.START_TAG_SIGN, "");
					if(s!=null&&s.startsWith(Constants.START_TAG_GPS))
						gps = s.replace(Constants.START_TAG_GPS, "");
								
				}
			
			String cbstr ="";
				//页面显示设置,调用页面名称为cbTicketSign的js函数
				cbstr= "javascript:cbTicketSign('"+
						words+"','"+
						Constants.SERVER_FILE_CONTENT_TICKET + sign+"','"+
						gps+"','"+
						signdate+"'"+
						")";				
			System.out.println("cbstr:"+cbstr);
			wvTicketOne.loadUrl(cbstr);
			//关闭提示对话框
			mDialog.dismiss();
		}

		@Override
		public String getName() {
			return "Login";
		}
	};

 

 页面JS针对Activity的回调函数和JS的普通函数没有多大区别，以下是上面Activity中调用的JS函数。

 

          //工作票签名回调
 	 function cbTicketSign(sAttr, words, sign, gps ,voice , date){
		if(sAttr=="workGroupSign"){
			$('#workGroupSignLbl').html(words);
			$('#workGroupSignLbl').hide();
			$('#workGroupSignImg').show();
			$("#workGroupSignImg").attr("src","${root }"+sign);						
			$("#workGroupSignGps").attr("src","${root}/images/ticket/gps.png");			
			$("#workGroupSignGps").bind("click",function(){ showGps(gps); }); 
			 
		}				
 	 }