用AsyncTask进行网络取图片

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1、新建一个XML，写一个Button,Imgview

<span style="font-size:18px;"><ImageView        android:id="@+id/imgviews"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        />    <Button         android:id="@+id/butns"         android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="AsyncTask网络取图"/></span>

2、新建一个Activty继承Activty，

这里对于控件实例化就不写出来了，直接进入主题

//点击按钮mButton获取网络图片

<span style="font-size:18px;">mButton2.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {getBitmapByAsyncTask("http://www.jimeise.net/wp-content/uploads/2014/05/IMGP6150.jpg");}});}private void getBitmapByThread(final String httpUrls){new Thread() {@Overridepublic void run() {URL url;try {url = new URL(httpUrls);HttpURLConnection connect = (HttpURLConnection) url.openConnection();InputStream is = connect.getInputStream();Bitmap bitmap = BitmapFactory.decodeStream(is);Message msg = Message.obtain();msg.obj = bitmap;mHandler.sendMessage(msg);} catch (MalformedURLException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}}.start();}//用AsyncTask进行网络取图片private void getBitmapByAsyncTask(String httpUrl) {new AsyncTask<String, Void, Bitmap>() {@Overrideprotected Bitmap doInBackground(String... params) {String httpurl = params[0];return DownLoadBitmap(httpurl);}protected void onPostExecute(Bitmap result) {if (result != null) {ImageView2.setImageBitmap(result);} else {Toast.makeText(MainActivity.this, "网络取图片出错!",Toast.LENGTH_SHORT).show();}};}.execute(httpUrl);}private Bitmap DownLoadBitmap(String httpUrl) {URL url;Bitmap bitmap = null;HttpURLConnection connect = null;InputStream is = null;try {url = new URL(httpUrl);connect = (HttpURLConnection) url.openConnection();is = connect.getInputStream();bitmap = BitmapFactory.decodeStream(is);} catch (MalformedURLException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {try {if (is != null) {is.close();}if (connect != null) {connect.disconnect();}} catch (IOException e) {e.printStackTrace();}}return bitmap;}</span>

里面全部是通过封装了的，直接调用。

强调一点就是网络取图片一定要在manifest里注册网络权限：

<span style="font-size:18px;">    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="17" /><uses-permission android:name="android.permission.INTERNET"/></span>

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