android学习记录（10）关于图片下载

图片下载一般是分为两个步骤：
1.（在新线程中）将输入流转换为字节数组下载,下载完之后把该close的都close掉，节省资源。
URL url =new URL(“此处传入下载地址”);
HttpURLConnection connection =(HttpURLConnection)url.openconnection();

private byte[] =picByte;
private String =
URL url =new URL("此处传入下载地址");
HttpURLConnection connection =(HttpURLConnection)url.openconnection();
InputStream is =connection.getInputStream();
ByteArrayOutputStream bao =new ByteArrayOutputStream();

int length =-1;
byte [] bytes =new byte[1024];
while((length =is.read(bytes)) !=-1){
	bao.write(bytes,0,length);
}

is.close();
bao.close();

2.将字节数组解析成Bitmap，然后显示出来。

private byte[] picByte;
private ImageView loadImg;
if(picByte !=null){
	Bitmap bitmap =BitmapFactory.decodeByteArray(picByte,0,picByte.length);
	loadImg.setImageBitmap(bitmap);
}