安卓Andriod与网页交互实现网页图片浏览----未完待续

理解：点击图片浏览的主要原理就是通过webview为网页中的html元素添加onclick事件，弹出activity

package com.topnews;

import android.annotation.SuppressLint;

import android.content.Context;

import android.content.Intent;

import android.graphics.Bitmap;

import android.os.AsyncTask;

import android.os.Bundle;

import android.text.TextUtils;

import android.util.Log;

import android.view.View;

import android.view.ViewGroup.LayoutParams;

import android.webkit.WebChromeClient;

import android.webkit.WebSettings;

import android.webkit.WebSettings.LayoutAlgorithm;

import android.webkit.WebView;

import android.webkit.WebViewClient;

import android.widget.FrameLayout;

import android.widget.ProgressBar;

import android.widget.TextView;

import com.topnews.base.BaseActivity;

import com.topnews.bean.NewsEntity;

import com.topnews.service.NewsDetailsService;

import com.topnews.tool.DateTools;

import java.util.ArrayList;

@SuppressLint("JavascriptInterface")

public class DetailsActivity extends BaseActivity {

private TextView title;

private ProgressBar progressBar;

private FrameLayout customview_layout;

private String news_url;

private String news_title;

private String news_source;

private String news_date;

private NewsEntity news;

private TextView action_comment_count;

WebView webView;

@Override

protected void onCreate(Bundle savedInstanceState) {

// TODO Auto-generated method stub

super.onCreate(savedInstanceState);

setContentView(R.layout.details);

setNeedBackGesture(true);//

getData();

initView();

initWebView();

}

private void getData() {

news = (NewsEntity) getIntent().getSerializableExtra("news");

news_url = news.getSource_url();

news_title = news.getTitle();

news_source = news.getSource();

news_date = DateTools.getNewsDetailsDate(String.valueOf(news.getPublishTime()));

}

private void initWebView() {

webView = (WebView)findViewById(R.id.wb_details);

LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.MATCH_PARENT);

if (!TextUtils.isEmpty(news_url)) {

WebSettings settings = webView.getSettings();

settings.setJavaScriptEnabled(true);

// settings.setTextZoom(120);//Sets the text zoom of the page in percent. The default is 100.

settings.setLayoutAlgorithm(LayoutAlgorithm.SINGLE_COLUMN);

settings.setAppCacheEnabled(true);

settings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);

// settings.setUseWideViewPort(true);

// settings.setLoadWithOverviewMode(true);

settings.setBuiltInZoomControls(false);

webView.setBackgroundResource(R.color.transparent);

webView.addJavascriptInterface(new JavascriptInterface(getApplicationContext()),"imagelistner");

webView.setWebChromeClient(new MyWebChromeClient());

webView.setWebViewClient(new MyWebViewClient());

new MyAsnycTask().execute(news_url, news_title, news_source + " " +news_date);

}

}

private void initView() {

title = (TextView) findViewById(R.id.title);

progressBar = (ProgressBar) findViewById(R.id.ss_htmlprogessbar);

customview_layout = (FrameLayout) findViewById(R.id.customview_layout);

action_comment_count = (TextView) findViewById(R.id.action_comment_count);

progressBar.setVisibility(View.VISIBLE);

title.setTextSize(13);

title.setVisibility(View.VISIBLE);

title.setText(news_url);

action_comment_count.setText(String.valueOf(news.getCommentNum()));

}

@Override

public void onBackPressed() {

super.onBackPressed();

overridePendingTransition(R.anim.slide_in_left, R.anim.slide_out_right);

}

private class MyAsnycTask extends AsyncTask<String, String,String>{

@Override

protected String doInBackground(String... urls) {

String data=NewsDetailsService.getNewsDetails(urls[0],urls[1],urls[2]);

return data;

}

@Override

protected void onPostExecute(String data) {

webView.loadDataWithBaseURL (null, data, "text/html", "utf-8",null);

}

}



//webView 通过loadUrl方法执行一段javascript方法，为网页中的元素添加javascript方法

private void addImageClickListner() {

webView.loadUrl("javascript:(function(){"

+ "var objs = document.getElementsByTagName(\"img\");"

+ "var imgurl=''; " + "for(var i=0;i<objs.length;i++) " + "{"

+ "imgurl+=objs[i].src+',';"

+ " objs[i].onclick=function() " + " { "

+ " window.imagelistner.openImage(imgurl); "

+ " } " + "}" + "})()");

}


//这是一个自定义的类，webView.addJavascriptInterface(new JavascriptInterface(getApplicationContext()),"imagelistner");方法把我们写的方法和

//webView结合在一起，这样在javascript中就可以通过window.imagelistner.openImage(imgurl); "调用了

public class JavascriptInterface {

private Context context;

public JavascriptInterface(Context context) {

this.context = context;

}

public void openImage(String img) {

//

String[] imgs = img.split(",");

ArrayList<String> imgsUrl = new ArrayList<String>();

for (String s : imgs) {

imgsUrl.add(s);

}

Intent intent = new Intent();

intent.putStringArrayListExtra("infos", imgsUrl);

intent.setClass(context, ImageShowActivity.class);

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

context.startActivity(intent);

}

}



private class MyWebViewClient extends WebViewClient {

@Override

public boolean shouldOverrideUrlLoading(WebView view, String url) {

return super.shouldOverrideUrlLoading(view, url);

}

@Override

public void onPageFinished(WebView view, String url) {

view.getSettings().setJavaScriptEnabled(true);

super.onPageFinished(view, url);

addImageClickListner();

progressBar.setVisibility(View.GONE);

webView.setVisibility(View.VISIBLE);

}

@Override

public void onPageStarted(WebView view, String url, Bitmap favicon) {

view.getSettings().setJavaScriptEnabled(true);

super.onPageStarted(view, url, favicon);

}

@Override

public void onReceivedError(WebView view, int errorCode,

String description, String failingUrl) {

progressBar.setVisibility(View.GONE);

super.onReceivedError(view, errorCode, description, failingUrl);

}

}

private class MyWebChromeClient extends WebChromeClient {

@Override

public void onProgressChanged(WebView view, int newProgress) {

// TODO Auto-generated method stub

if(newProgress != 100){

progressBar.setProgress(newProgress);

}

super.onProgressChanged(view, newProgress);

}

}

}