Android网络图片异步加载

dialog= ProgressDialog.show(this,"","加载数据，请稍等 …",true,true);
//图片资源
String url = "http://www.kzwlg.com.cn:1080/Wlg_server2/"+bundle.getString("pic");
//得到可用的图片
getHttpBitmap(url);

/**
* 对图片进行大小缩放
* @param bm
* @param newWidth
* @param newHeight
* @return
*/
protected Bitmap scaleImg(Bitmap bm, int newWidth, int newHeight) {
// 图片源
// Bitmap bm = BitmapFactory.decodeStream(getResources()
// .openRawResource(id));
// 获得图片的宽高
int width = bm.getWidth();
int height = bm.getHeight();
// 设置想要的大小
int newWidth1 = newWidth;
int newHeight1 = newHeight;
// 计算缩放比例
float scaleWidth = ((float) newWidth1) / width;
float scaleHeight = ((float) newHeight1) / height;
// 取得想要缩放的matrix参数
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
// 得到新的图片
Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,
true);
return newbm;
}

/**
* 处理ImageView
*/
final Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
image.setImageBitmap(scaleImg(bitmap, 300, 300));
dialog.dismiss();
break;
default:
break;
}

}
};
/**
* 从网络位置得到图片
* 采用handler+Thread模式实现多线程异步加载
* @param url
* @return
*/
private void getHttpBitmap( final String url) {

Thread thread=new Thread(){
public void run() {
URL myFileURL;

try{
myFileURL=new URL(url);
//获得连接
HttpURLConnection conn=(HttpURLConnection)myFileURL.openConnection();
//设置超时时间为6000毫秒，conn.setConnectionTiem(0);表示没有时间限制
conn.setConnectTimeout(6000);
//连接设置获得数据流
conn.setDoInput(true);
//不使用缓存
conn.setUseCaches(false);
//这句可有可无，没有影响
//conn.connect();
//得到数据流
InputStream is = conn.getInputStream();
//解析得到图片
bitmap = BitmapFactory.decodeStream(is);
//关闭数据流
is.close();

Message message = handler.obtainMessage();
message.what=1;
handler.sendMessage(message);
}catch(Exception e){
e.printStackTrace();
}

};
};
thread.start();
thread=null;
}