Android中如何根据URL获取图片
1、如下图所示,需要根据URL地址获取图片加载到图中Anroid机器人所在的位置,这是运行前的效果:
2、首先需根据UR雉搽妤粲L地址获取图片,如下所示,urladdr即为图片地址,返回Drawable对象: //download image from network using @urladdress private Drawable loadImageFromNetwork(String urladdr) {// TODO Auto-generated method stubDrawable drawable = null;try{ //judge if has picture locate or not according to filename drawable = Drawable.createFromStream(new URL(urladdr).openStream(), "image.jpg"); }catch(IOException e){ Log.d("test",e.getMessage()); } if(drawable == null){ Log.d("test","null drawable"); }else{ Log.d("test","not null drawable"); } return drawable; }
3、获取到图片后,需要更新主线程UI资源,考虑到时间以及界面反应延迟等,所以采用线程加以处理,如下图所示:// image new Thread(new Runnable()撑俯擂摔{ Drawable drawable = loadImageFromNetwork(urladdress); @Override public void run(){ //post() is quite important,update pictures in UI main thread image.post(new Runnable(){ @Override public void run(){ //TODO Auto-generated method stub image.setImageDrawable(drawable); } }); } //download image from network using @urladdress private Drawable loadImageFromNetwork(String urladdr) { //... 略(如 1 中所示)}}).start(); //线程启动
4、说明:在上述示例代码中,image是ImageView类的一个对象,也就是APP中的一个显示图像组件,利用获取到的图片drawable去更新image,运行效果如下所示: