Android Development Series (12): Get pictures on the web

The process of acquiring a network slice:

Get a picture of the url-> by URL Connection picture Object--read the binary data of the picture to write to memory--and return to memory data--show it

First, we want to add permissions

Because we want to access the network, we will always add network access to the Androidmanifest.xml file:

<!--access to INTERNET rights--><uses-permission android:name= "Android.permission.INTERNET"/>

Then there is the Setup interface: Main.xml:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/    Android "android:orientation=" vertical "android:layout_width=" fill_parent "android:layout_height=" Fill_parent " ><textview android:layout_width= "fill_parent" android:layout_height= "wrap_content" android:text= "@stri     Ng/imagepath "/> <edittext android:layout_width=" fill_parent "android:layout_height=" Wrap_content " Android:text= "http://b.hiphotos.baidu.com/image/w%3D310/sign=1d7f12db95dda144da096ab382b5d009/ 8d5494eef01f3a293c5d63069b25bc315d607c64.jpg "android:id=" @+id/imagepath "/> <button android:layout_ Width= "Wrap_content" android:layout_height= "wrap_content" android:text= "@string/button" android:id= "@+id/button "/> <imageview android:layout_width=" wrap_content "android:layout_height=" Wrap_content "Android : id= "@+id/imageview"/></linearlayout>

Next is the Mainactivity.java file:

Package Cn.itcast.image;import Cn.itcast.service.imageservice;import Android.app.activity;import Android.graphics.bitmap;import Android.graphics.bitmapfactory;import Android.os.bundle;import Android.view.View; Import Android.widget.button;import Android.widget.edittext;import Android.widget.imageview;import    Android.widget.toast;public class Mainactivity extends Activity {private EditText pathtext;        Private ImageView ImageView;        @Override public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);                Setcontentview (R.layout.main);        Pathtext = (EditText) This.findviewbyid (R.id.imagepath);        ImageView = (ImageView) This.findviewbyid (R.id.imageview);        Button button = (button) This.findviewbyid (R.id.button);    Button.setonclicklistener (New Buttonclicklistener ()); } Private Final class Buttonclicklistener implements View.onclicklistener{public void OnClick (View v) {String path = Pathtext.gettext (). toStRing (); Get the URL path of the text box try{//get the binary data of the picture byte[] data = imageservice.getimage (path);//convert the picture to bitmap type bitmap bitmap = Bitmapfactory.decodebytearray (data, 0, data.length); Imageview.setimagebitmap (bitmap);//Display Picture}catch (Exception e) { E.printstacktrace ();    Toast.maketext (Getapplicationcontext (), R.string.error, 1). Show ();}} }}

Then we will also configure the Imageservice.java file:

Package Cn.itcast.service;import Java.io.inputstream;import Java.net.httpurlconnection;import java.net.URL;import Cn.itcast.utils.streamtool;public class ImageService {/** * get data for a network picture * @param path network picture paths * @return */public static byte[ ] GetImage (String path) throws exception{//get urlurl url = new URL (path); HttpURLConnection conn = (httpurlconnection) url.openconnection ();//HTTP protocol-based Connection object Conn.setconnecttimeout (5000); Conn.setrequestmethod ("get");//set to submit if (conn.getresponsecode () = = 200) {//If the response code equals 200 is the request succeeds InputStream instream = Conn.getinputstream (); Get input stream return Streamtool.read (instream); Get picture binary data}return null;}}

Finally we will add a tool class:

Package Cn.itcast.utils;import Java.io.bytearrayoutputstream;import Java.io.inputstream;public class StreamTool {/** * Read data in stream * @param instream * @return * @throws Exception */public static byte[] Read (InputStream instream) throws Excepti On{bytearrayoutputstream OutStream = new Bytearrayoutputstream (); byte[] buffer = new Byte[1024];int len = 0;while (len = Instream.read (buffer))! =-1) {//instream.read (buffer) returns INT: The length of the data read, and when read-1 is finished reading Outstream.write (buffer, 0, Len); Writes the read data to the memory}instream.close (); return Outstream.tobytearray (); Returns the data in Memory}}

As follows:

Android Development Series (12): Get pictures on the web