android 学习

获取assets资源

assets文件夹目录与java目录时同级

/**
     * 获取Assets 文件内容
     * @param fileName 文件名
     * @param context context
     * @return String
     */
    public static String getJson(String fileName, Context context) {
        //将json数据变成字符串
        StringBuilder stringBuilder = new StringBuilder();
        try {
            //获取assets资源管理器
            AssetManager assetManager = context.getAssets();
            //通过管理器打开文件并读取
            BufferedReader bf = new BufferedReader(new InputStreamReader(assetManager.open(fileName)));
            String line;
            while ((line = bf.readLine()) != null) {
                stringBuilder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return stringBuilder.toString();
}

gosn解析json

Gson gson=new Gson();
Bean data=gson.fromJson(string,Bean.class);//Bean时定义的实体类

// 从assets中获取json内容并解析
//json内容为
/*
[{"center":[116.41338310930209,37.60701416950952],"id":"0-0"}] //注:类型为Bean
*/
try {
    JSONArray gridDataList = new JSONArray(Utils.getJson("map_grid_data.json", HomeActivity.this));//获取JSONArray
    Type listType = new TypeToken<List<Bean>>() {
    }.getType();//获取类型
    List<Bean> list = new Gson().fromJson(gridDataList.toString(), listType);
    Log.d("HomeActivity", list.toString());
} catch (JSONException e) {
    e.printStackTrace();
}