android - 如何在 Android 中从 JSON url 解析图像？

Question

我正在解析来自 Wordpress 博客的内容。我不知道如何从 JSON 获取图像.这是图片网址 "content":"<p><img class=\"aligncenter\" style=\"cursor: -moz-zoom-in;\" src=\"http:\/\/sphotos-h.ak.fbcdn.net\/hphotos-ak-ash4\/395050_10151219612828815_5123523_n.jpg\" alt=\"http:\/\/sphotos-h.ak.fbcdn.net\/hphotos-ak-ash4\/395050_10151219612828815_5123523_n.jpg\" width=\"390\" height=\"466\" \/><\/p>\n<p><span id=\"more-5267\"><\/span><\/p>\n<p>Some texts here...XXXXXYYYYYZZZZ"

HttpClient client;
HttpGet get;
HttpResponse res;
HttpEntity ent;
Button b;
TextView tv1,tv2,tv3;
@TargetApi(Build.VERSION_CODES.GINGERBREAD)
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    Typeface tp=Typeface.createFromAsset(getAssets(), "AftaSansThin-Regular.otf");
    StrictMode.enableDefaults();
    b = (Button) findViewById(R.id.button1);
    tv1 = (TextView) findViewById(R.id.textView1);
    tv2 = (TextView) findViewById(R.id.textView2);
    tv3 = (TextView) findViewById(R.id.textView3);
    tv1.setTypeface(tp);
    tv2.setTypeface(tp);
    tv3.setTypeface(tp);
    client = new DefaultHttpClient();
    get = new HttpGet("http://example.com");
    b.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            try {
                res=client.execute(get);
            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            ent=res.getEntity();
            InputStream is = null;
            try {
                is=ent.getContent();
            } catch (IllegalStateException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            BufferedReader br = new BufferedReader(new InputStreamReader(is));
            StringBuffer sb = new StringBuffer();
            String line = null;
            do{
                try {
                    line = br.readLine();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                sb.append(line);
            } while (line!=null);
            String str = sb.toString();

            try {
                JSONObject ob1 = new JSONObject(str);
                JSONObject ob2 = ob1.getJSONObject("post");
                String title = ob2.getString("title");
                String date = ob2.getString("date");
                String content = ob2.getString("content");



                tv1.setText(title);
                tv2.setText(date);
                Spanned marked_up = Html.fromHtml(content);
                tv3.setText(marked_up.toString(),BufferType.SPANNABLE);

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });
}

Answer 1

首先，这不是一个有效的图像 Url -\"http://sphotos-h.ak.fbcdn.net/hphotos-ak-ash4/395050_10151219612828815_5123523_n.jpg\"更接近你想要的，但仍然有所有转义字符。

如果您可以让 JSON 数据包将 URL 作为字符串发送，效率会高得多。如果不对其进行配置，使其不会转义所有字符，则从返回的文本中删除 Url。

接下来，我要做的是在 AsyncTask 中启动一个 http 连接并获取一个输入流。使用 BitmapFactory.decodeStream(HttpInputStream) 将流转换为位图，然后将位图返回给 UI 线程 onPostExecute。

如果您要处理许多图像下载，您可能需要考虑一个开源库或编写一个 AsyncImageLoader

希望这有帮助:)