【android】從網路擷取圖片的三種方法

http://blog.csdn.net/ameyume/article/details/6089334

以上連結：實現圖片的放大縮小

http://blog.csdn.net/kesenhoo/article/details/6534757

以上連結：用另一種思路實現~~~（改天認真讀一下）

http://doinone.iteye.com/blog/1074283

1.直接擷取：（容易：ANR，不建議）

mImageView = (ImageView)this.findViewById(R.id.imageThreadConcept) ;Drawable drawable = loadImageFromNetwork(IMAGE_URL);mImageView.setImageDrawable(drawable) ;

private Drawable loadImageFromNetwork(String imageUrl){    Drawable drawable = null;    try {        // 可以在這裡通過檔案名稱來判斷，是否本地有此圖片        drawable = Drawable.createFromStream(                new URL(imageUrl).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 ;}

 

2. 後台線程擷取url圖片：

mImageView = (ImageView)this.findViewById(R.id.imageThreadConcept) ;new Thread(new Runnable(){    Drawable drawable = loadImageFromNetwork(IMAGE_URL);    @Override    public void run() {                // post() 特別關鍵，就是到UI主線程去更新圖片                        mImageView.post(new Runnable(){        @Override        public void run() {            // TODO Auto-generated method stub            mImageView.setImageDrawable(drawable) ;        }}) ;        }        }).start()  ;

3.AsyncTask擷取url圖片

mImageView = (ImageView)this.findViewById(R.id.imageThreadConcept) ;new DownloadImageTask().execute(IMAGE_URL) ;private class DownloadImageTask extends AsyncTask<String, Void, Drawable> {                protected Drawable doInBackground(String... urls) {            return loadImageFromNetwork(urls[0]);        }        protected void onPostExecute(Drawable result) {            mImageView.setImageDrawable(result);        }}

比較三種方法，感覺代碼簡潔方面用第三方法不錯。