Question

我有一个方法可以进行api调用并解析响应。我在onResponse方法中得到当前天气的整数值。我想将此值设置为textview但是在onResponse方法值之后不保留。我把这个变量也变成了全局变量。这个类扩展了片段，所以我在onViewCreated方法中设置了值。

这是带日志的方法代码......

public class HomeScreen extends Fragment{
int currentWeather = 0;

onViewCreated(){
 curWeather = ... initialisation.
 curWeather.setText(""+getCurrentWeather);
}

public int getCurrentWeather(){

    OkHttpClient okHttpClient = new OkHttpClient();
    Request re = new Request.Builder().url(forecastURL).build();
    Call call = okHttpClient.newCall(re);
    call.enqueue(new Callback() {
        @Override
        public void onFailure(Call call, IOException e) {

        }

        @Override
        public void onResponse(Call call, Response response) throws IOException {
            String jsonResponse = response.body().string();
            JSONObject forecast;
            JSONObject currently;
            try {
                forecast = new JSONObject(jsonResponse);
                currently = forecast.getJSONObject("currently");
                currentTempFaron = (int) Math.round(currently.getDouble("temperature"));
                currentTempCelc = (currentTempFaron - 32) * 5 / 9;

                Log.d("weather in try", "" + currentTempCelc); // has weather value
            } catch (JSONException e) {
                e.printStackTrace();
            }
            Log.d("weather in response", "" + currentTempCelc); // again has weather value.
        }
    });
return currentTempCelc; //nothing it has at this point after coming out of response.
}

}

Answer 1

在onResponse()之后Log.d("weather in response", "" + currentTempCelc);内执行此操作：

getActivity().runOnUiThread(new Runnable() {
    @Override
    public void run() {
        curWeather.setText(Integer.toString(currentTempCelc));
    }
});

这里的问题是你试图从后台线程更新UI线程，这是不允许的。您可以使用runOnUiThread来实现此目的。

Answer 2

使用Handler更新onResponse

中的UI组件

new Handler(Looper.getMainLooper()).post(new Runnable() {
    @Override
    public void run() {
        curWeather.setText(Integer.toString(currentTempCelc));
        }
    }
});

Answer 3

在curWeather中创建Fragment成员变量。然后在setText方法中的curWeather上致电onResponse。

public class HomeScreen extends Fragment{
int currentWeather = 0;
final TextView curWeather

onViewCreated(){
 curWeather = ... initialisation.
 // curWeather.setText(""+getCurrentWeather);
}

public int getCurrentWeather(){

    OkHttpClient okHttpClient = new OkHttpClient();
    Request re = new Request.Builder().url(forecastURL).build();
    Call call = okHttpClient.newCall(re);
    call.enqueue(new Callback() {
        @Override
        public void onFailure(Call call, IOException e) {

        }

        @Override
        public void onResponse(Call call, Response response) throws IOException {
            String jsonResponse = response.body().string();
            JSONObject forecast;
            JSONObject currently;
            try {
                forecast = new JSONObject(jsonResponse);
                currently = forecast.getJSONObject("currently");
                currentTempFaron = (int) Math.round(currently.getDouble("temperature"));
                currentTempCelc = (currentTempFaron - 32) * 5 / 9;

                Log.d("weather in try", "" + currentTempCelc); // has weather value
                curWeather.setText(""+currentTempCelc);
            } catch (JSONException e) {
                e.printStackTrace();
            }
            Log.d("weather in response", "" + currentTempCelc); // again has weather value.
        }
    });
return currentTempCelc; //nothing it has at this point after coming out of response.
}

Answer 4

您可以使用方法 getCurrentWeather（）传递活动上下文。然后您可以访问TextView并设置TextView。我尝试了这个解决方案，它对我有用。

在回调方法响应之后无法获取整数的值

4 个答案: