java - 如何从 JSON 中提取图像的 url(LastFM API)

Question

我是 JSON 使用的初学者。

所以我尝试从 JSON 回复中提取图像的 url。

这是允许我获取数组的代码:

            // Instantiate the RequestQueue.
            RequestQueue queue = Volley.newRequestQueue(getActivity());
            //String url ="http://www.google.com";
            String url = "http://ws.audioscrobbler.com/2.0/?method=album.search&album="+albumName+"&api_key=c51f8eb36bad&format=json";


            // Request a string response from the provided URL.
            StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
                    new Response.Listener<String>() {
                        @Override
                        public void onResponse(String response) {
                            // Display the first 500 characters of the response string.
                            //mTextView.setText("Response is: "+ response.substring(0,500));
                            Log.i("RESPONSE","Response is: "+ response);

                            JSONObject jsono = new JSONObject();
                            try {
                                jsono = new JSONObject(response);
                                //String url = jsono.getString("results");


                                //Log.i("RESPONSE",url);
                            } catch (JSONException e) {
                                e.printStackTrace();
                                Log.d ("RESPONSE",e.getMessage());
                            }
                            JSONArray jsonArray = new JSONArray();
                            try {
                                jsonArray = jsono.getJSONObject("results").getJSONObject("albummatches").getJSONArray("album");
                            } catch (JSONException e) {
                                e.printStackTrace();
                                Log.d ("RESPONSE",e.getMessage());
                            }
                            for (int i = 0; i < jsonArray.length(); i++) {
                                JSONObject object = new JSONObject();
                                try {
                                    object = jsonArray.getJSONObject(i);
                                    Log.i("RESPONSE",object.getString("image"));

                                } catch (JSONException e) {
                                    e.printStackTrace();
                                }

                            }
                        }
                    }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Log.i("RESPONSE","That didn't work!");
                }
            });
            queue.add(stringRequest);

这是 JSON 答案中这部分的结构:

    {

    "album": [
        {
            "name": "DD Y Ponle Play",
            "artist": "Jumbo",
            "id": "2528039",
            "url": "http://www.last.fm/music/Jumbo/DD+Y+Ponle+Play",
            "image": [
                {
                    "#text": "http://images.amazon.com/images/P/B00005LN6S.01._SCMZZZZZZZ_.jpg",
                    "size": "small"
                },
                {
                    "#text": "http://images.amazon.com/images/P/B00005LN6S.01._SCMZZZZZZZ_.jpg",
                    "size": "medium"
                },
                {
                    "#text": "http://images.amazon.com/images/P/B00005LN6S.01._SCMZZZZZZZ_.jpg",
                    "size": "large"
                },
                {
                    "#text": "http://images.amazon.com/images/P/B00005LN6S.01._SCMZZZZZZZ_.jpg",
                    "size": "extralarge"
                }
            ]
        }
    ]
}

如何获取给定尺寸的图像的 URL？

非常感谢您的建议。

Answer 1

您可以使用谷歌 GSON 来实现此目的。将其作为依赖项导入

首先创建一个相册类。

public class Albums {

private List<Album> album;

public List<Album> getAlbum() {
    return album;
}

public class Album{
    private String name;
    private String artist;
    private String id;
    private String url;

    public String getName() {
        return name;
    }

    public String getArtist() {
        return artist;
    }

    public String getId() {
        return id;
    }

    public String getUrl() {
        return url;
    }

    public List<Image> getImage() {
        return image;
    }

    public class Image {
        @SerializedName("#text")
        private String text;
        private String size;

        public String getText() {
            return text;
        }

        public String getSize() {
            return size;
        }
    }

    private List<Image> image;
}

}

现在，在您获取上述 JSON 对象的代码中尝试下面的代码

Gson gson = new Gson();

// Im assuming "response" as the above JSON object
Albums albums = gson.fromJson(response.optString("album"),Albums.class);

这会将您的 json 映射到 java 对象。(注意:您可以根据需要从 POJO 中删除不需要的对象)

您可以使用 getter 函数获取图像