如何将JSON数组转换为浮点数数组。

Question

我想从JSON数组中获取数据，我想为我的条形图制作常规浮点数数组，但是如何将JSON数组转换为浮点数数组。

public class fragment extends Fragment {
public fragment() {
    // Required empty public constructor
}


final static String TAG = "ok";

BarChart barChart;

float datay [];
float datay1 [];
String datax [];
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View fragment = inflater.inflate(R.layout.fragment1, container, false);

    barChart = (BarChart)fragment.findViewById(R.id.barchart);

    fetchData();


    return  fragment;
}

public void fetchData(){
    showLoading("Loading");
    StringRequest strReq = new StringRequest(Request.Method.POST,
            AppConfig.CHART, new Response.Listener<String>() {

        @Override
        public void onResponse(String response) {
            hideLoading();
            try {
                Log.d(TAG,"ini response"+response);
                JSONObject object = new JSONObject(response);
                //datacatagory for datax
                JSONArray datacatagory = object.getJSONArray("category");
                Log.d(TAG,"catagory"+datacatagory);
                JSONArray jdata1 = object.getJSONArray("data");
                Log.d(TAG,"jdata"+jdata1);
                JSONObject obj1 = jdata1.getJSONObject(1);
                Log.d(TAG,"obj"+obj1);
                // arr1 for datay
                JSONArray arr1 = obj1.getJSONArray("data");
                Log.d(TAG,"arr"+arr1);
                //arr2 for datay1
                JSONArray arr2 = obj1.getJSONArray("data");
                Log.d(TAG,"arr"+arr1);

                //how convert data jsonarray to regular array in java??

                chartListener(datay,datax,datay1);


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

        }
    }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            getToast(error.getMessage());
            hideLoading();
        }
    }) {

        @Override
        protected Map<String, String> getParams() {
            return getPOST("laba_rugi");
        }

    };

    addRequestQueen(strReq,TAG);

}


public void chartListener(float datay[],String datax[],float data1[]){
    barChart.setDescription("ok");
    ArrayList<BarEntry> ydata = new ArrayList<>();
    for (int i = 0;i< datay.length;i++){
        ydata.add(new BarEntry(datay[i],i));
    }

    ArrayList<BarEntry> ydata1 = new ArrayList<>();
    for (int i = 0;i< datay.length;i++){
        ydata1.add(new BarEntry(data1[i],i));
    }

    ArrayList<String> xdata = new ArrayList<>();
    for (int i = 0;i < datax.length;i++){
        xdata.add(datax[i]);
    }

    BarDataSet barDataSet = new BarDataSet(ydata,"rugi");
    barDataSet.setColors(ColorTemplate.PASTEL_COLORS);

    BarDataSet barDataSet1 = new BarDataSet(ydata1,"laba");
    barDataSet.setColors(ColorTemplate.JOYFUL_COLORS);

    ArrayList<BarDataSet> dataSets = new ArrayList<>();  // combined all dataset into an arraylist
    dataSets.add(barDataSet);
    dataSets.add(barDataSet1);

    BarData barData = new BarData(xdata,dataSets);
    barData.setValueTextSize(13f);
    barData.setValueTextColor(Color.BLACK);

    int a =00000;
    barChart.setData(barData);
    barChart.setBackgroundColor(a);
    barChart.invalidate();
}
}

我想从json数组中获取数据，我想为我的条形图创建常规的浮点数数组。但是，如何将json数组更改为浮点数数组？请帮助我。

- Said

Answer 1

这个简单的方法应该会对你有所帮助。虽然没有测试，但应该可以使用。

private float[] fillData(JSONArray jsonArray){

    float[] fData = new float[jsonArray.length()];

    for (int i = 0; i < jsonArray.length(); i++) {
        try {
            fData[i] = Float.parseFloat(jsonArray.getString(i));
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

    return fData;
}

只需按以下方式编写此方法，即可获得浮点数组：

JSONArray arr1 = obj1.getJSONArray("data");
float[] data = fillData(arr1);

- JavadKhan

---

抱歉，我仍然不明白，请给我一个关于float数据数组的直接示例。 - Said

float datay[];是我想要将JSONArray arr1更改为的内容。 - Said

好的，这是我的日志：[32.534,46.436,0,6.565,0,7,7.777,77.457,4,0,63.463,3.453,0,0,3.453,253,0,0,4.535,0,34.543,0,55,646,0,56.565,0,0,0,0,0] - Said

@你可以在询问之前进行测试))) - JavadKhan

非常感谢！操作成功了！但是如果我要将数据转换为字符串呢？ - Said