如何在JSON对象响应中访问JSONArray内部的JSONArray

Question

在此Json响应中，如何使用Java访问“ smallImageUrls”并获取图像URL？

似乎“ smallImageUrls”是“ matches” jsonarray中的一个数组。 如果我做错了，请有人纠正我。

{  
   "attribution":{  
      "html":"Recipe search powered by <a href='http://www.yummly.com/recipes'><img alt='Yummly' src='http://static.yummly.com/api-logo.png'/></a>",
  "url":"http://www.yummly.com/recipes/",
  "text":"Recipe search powered by Yummly",
  "logo":"http://static.yummly.com/api-logo.png"
   },
"totalMatchCount":17663,
"facetCounts":{  

},
"matches":[  
  {  
     "imageUrlsBySize":{  
        "90":"http://lh3.ggpht.com/bTkxROvVTjHChEsGLRnkuwPoi-eNrHmESYP3xDHMsIisN-U06z-OfwErSjT5AHvMG0Ccgw8cN4mVqNyjWzbz=s90-c"
     },
     "sourceDisplayName":"Serious Eats",
     "ingredients":[  
        "mayonnaise",
        "crema mexican",
        "feta",
        "ancho powder",
        "garlic",
        "coriander leaf",
        "shuck corn",
        "lime"
     ],
     "id":"Mexican-street-corn-_elotes_-370469",
     "smallImageUrls":[  
        "http://lh5.ggpht.com/itong2VhnBU2mvPtzNimL58MnkC4l113RgNyrEWq8Jf76AsOGOlBoVQyCF-jYDPtzTB-7SoViNzyV5-Xe0NS=s90"
     ],
     "recipeName":"Mexican Street Corn (Elotes)",
     "totalTimeInSeconds":2400,
     "attributes":{  
        "cuisine":[  
           "Mexican"
        ]
     },
     "flavors":{  
        "sweet":0.5,
        "sour":0.6666666666666666,
        "salty":0.6666666666666666,
        "piquant":0.3333333333333333,
        "meaty":0.3333333333333333,
        "bitter":0.6666666666666666
     },
     "rating":5
  }
],
"criteria":{  
  "excludedIngredients":null,
  "allowedIngredients":null,
  "terms":null
}
 }

这是我目前拥有的代码。 我可以访问所有其他字符串，而不能访问图像url。

 JSONObject resObj = new JSONObject(result);
                 JSONArray foundrecipes = resObj.getJSONArray("matches");
                for(int i = 0;i<foundrecipes.length(); i++){
                    JSONObject recipe = foundrecipes.getJSONObject(i);
                    String recipeName = recipe.getString("recipeName");
                     String rating = recipe.getString("rating");
                    String id = recipe.getString("id");
                    String imageurl = recipe.getString("smallImageUrls");

                data.add(new Recipes(recipeName, rating, id, imageurl));
            }

Answer 1

smallImageUrls位于根目录内的匹配项中，因此您必须检索匹配项，并通过它来检索smallImageUrls

JSONObject obj = new JSONObject(...);
JSONArray matches = obj.optJSONArray("matches");
if (matches != null) {
 for (int i = 0; i < matchesLenght; i++) {
    JSONObject objAtIndex =  matches.optJSONObject(i);
    if (objAtIndex != null) {
         JSONArray smallImageUrls = objAtIndex.optJSONArray("smallImageUrls");
         for (int j = 0; j < smallImageUrlsSize; j++) {
              String urlAtIndex = smallImageUrls.optString(j);
         }
    }
 }

}