链接Fragment和Activity之间的天气数据连接

Question

我正在使用https://openweathermap.org/current构建一个天气应用程序，到目前为止，一切都很顺利。应用程序的活动部分使用城市查询从我的界面给出任何城市的当前数据在编辑文本上搜索。现在的问题是，我只使用一个搜索按钮(在我的活动上)，但我也想在片段类中接收相同的数据。例如，我使用活动:1.搜索并显示城市名称。2. 显示这些城市的当前时间。

以及获取temp, sunrise &日落，湿度，以及在活动上搜索的城市的其他数据。

所以我不能实现双搜索按钮(在活动和片段)只是为了获得数据。我的目标是使用自己的活动来获得城市数据在这两个类，因为我的片段类也包含接收数据的textviews，我会欣赏任何方法来实现这一点，因为我不知道如何做到这一点自己。

我尝试在片段类上调用相同的方法，但我从片段中的此代码中获得编译错误:

private void getWeatherData(String name) {
ApiInterface apiInterface = ApiClient.getClient().create(ApiInterface.class);
Call<Example> call = apiInterface.getWeatherData(name);

说:'getWeatherData' is never used和cannot resolve symbol 'name'(因为我的搜索按钮和edittext单独用于活动)

我没有得到一个单一的错误活动

这是我的完整代码:

HomeActivity.java

public class HomeActivity extends AppCompatActivity {
// User current time
TextView time_field;
ImageView Search;
EditText textfield;
ConstraintLayout constraintLayout;
public static int count=0;
int[] drawable =new int[]{R.drawable.dubai,R.drawable.central_bank_of_nigeria,R.drawable.eiffel_tower,R.drawable.hong_kong,R.drawable.statue_of_liberty};
Timer _t;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
time_field = findViewById(R.id.textView9);
Search = findViewById(R.id.imageView4);
textfield = findViewById(R.id.textfield);
BottomNavigationView bottomNavigationView = findViewById(R.id.bottomNavigationView);
NavController navController = Navigation.findNavController(this, R.id.fragment);
NavigationUI.setupWithNavController(bottomNavigationView, navController);
Search.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {

getWeatherData(textfield.getText().toString().trim());

constraintLayout = findViewById(R.id.layout);
constraintLayout.setBackgroundResource(R.drawable.dubai);
_t = new Timer();
_t.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
// run on ui thread
runOnUiThread(() -> {
if (count < drawable.length) {
constraintLayout.setBackgroundResource(drawable[count]);
count = (count + 1) % drawable.length;
}
});
}
}, 5000, 5000);
}
private void getWeatherData(String name) {
ApiInterface apiInterface = ApiClient.getClient().create(ApiInterface.class);
Call<Example> call = apiInterface.getWeatherData(name);
call.enqueue(new Callback<Example>() {
@Override
public void onResponse(@NotNull Call<Example> call, @NotNull Response<Example> response) {
assert response.body() != null;
time_field.setText(String.valueOf(response.body().getDt()));

}
@Override
public void onFailure(@NotNull Call<Example> call, @NotNull Throwable t) {
t.printStackTrace();
}

});
}


});
}
}

FirstFragment.java

public class FirstFragment extends Fragment {
// User current time, current temperature, current condition, sunrise, sunset, temperature, pressure, humidity, wind_speed, visibility, clouds
TextView current_temp, current_output, rise_time, set_time, temp_out, Press_out, Humid_out, Ws_out, Visi_out, Cloud_out;
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
public FirstFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* @param param1 Parameter 1.
* @param param2 Parameter 2.
* @return A new instance of fragment SecondFragment.
*/
// TODO: Rename and change types and number of parameters
public static FirstFragment newInstance(String param1, String param2) {
FirstFragment fragment = new FirstFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_first, container, false);
current_temp = rootView.findViewById(R.id.textView10);
current_output = rootView.findViewById(R.id.textView11);
rise_time = rootView.findViewById(R.id.textView25);
set_time = rootView.findViewById(R.id.textView26);
temp_out = rootView.findViewById(R.id.textView28);
Press_out = rootView.findViewById(R.id.textView29);
Humid_out = rootView.findViewById(R.id.textView30);
Ws_out = rootView.findViewById(R.id.textView33);
Visi_out = rootView.findViewById(R.id.textView34);
Cloud_out = rootView.findViewById(R.id.textView35);
private void getWeatherData(String name) {
ApiInterface apiInterface = ApiClient.getClient().create(ApiInterface.class);
Call<Example> call = apiInterface.getWeatherData(name);
call.enqueue(new Callback<Example>() {
@Override
public void onResponse(@NotNull Call<Example> call, @NotNull Response<Example> response) {
current_temp.setText(response.body().getMain().getTemp() + " ℃");
current_output.setText(response.body().getWeatherList().get(0).getDescription());
rise_time.setText(response.body().getSys().getSunrise() + " ");
set_time.setText(response.body().getSys().getSunset() + " ");
temp_out.setText(response.body().getMain().getTemp() + " ℃");
Press_out.setText(response.body().getMain().getPressure() + " hpa");
Humid_out.setText(response.body().getMain().getHumidity() + " %");
Ws_out.setText(response.body().getWind().getSpeed() + " Km/h");
Visi_out.setText(response.body().getVisibility() + " m");
Cloud_out.setText(response.body().getClouds().getAll()+ " %");
}
@Override
public void onFailure(@NotNull Call<Example> call, @NotNull Throwable t) {
t.printStackTrace();
}
});
}
return rootView;
}
}

ApiInterface:

public interface ApiInterface {
@GET("weather?&appid=(My app key)&units=metric")
Call<Example> getWeatherData(@Query("q") String name);
}

ApiClient:

public class ApiClient {
private static Retrofit retrofit = null;
public static  Retrofit getClient(){ //creating object
if (retrofit == null) {
retrofit = new Retrofit.Builder()
.baseUrl("https://api.openweathermap.org/data/2.5/")
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}

Answer 1

您正在使用与语法不同的java方法:

你没有得到任何错误在你的活动，因为你已经定义了一个匿名类内，但你得到一个错误在你的片段，因为你已经写在另一个方法内，这在java中是不ok的。

所以，把你的方法写出来(在onCreateView之外)，然后在那里调用它。

public class FirstFragment extends Fragment {
// User current time, current temperature, current condition, sunrise, sunset, temperature, pressure, humidity, wind_speed, visibility, clouds
TextView current_temp, current_output, rise_time, set_time, temp_out, Press_out, Humid_out, Ws_out, Visi_out, Cloud_out;
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
public FirstFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* @param param1 Parameter 1.
* @param param2 Parameter 2.
* @return A new instance of fragment SecondFragment.
*/
// TODO: Rename and change types and number of parameters
public static FirstFragment newInstance(String param1, String param2) {
FirstFragment fragment = new FirstFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_first, container, false);
current_temp = rootView.findViewById(R.id.textView10);
current_output = rootView.findViewById(R.id.textView11);
rise_time = rootView.findViewById(R.id.textView25);
set_time = rootView.findViewById(R.id.textView26);
temp_out = rootView.findViewById(R.id.textView28);
Press_out = rootView.findViewById(R.id.textView29);
Humid_out = rootView.findViewById(R.id.textView30);
Ws_out = rootView.findViewById(R.id.textView33);
Visi_out = rootView.findViewById(R.id.textView34);
Cloud_out = rootView.findViewById(R.id.textView35);
getWeatherData("Blah blah blah");
return rootView;
}
private void getWeatherData(String name) {
ApiInterface apiInterface = ApiClient.getClient().create(ApiInterface.class);
Call<Example> call = apiInterface.getWeatherData(name);
call.enqueue(new Callback<Example>() {
@Override
public void onResponse(@NotNull Call<Example> call, @NotNull Response<Example> response) {
current_temp.setText(response.body().getMain().getTemp() + " ℃");
current_output.setText(response.body().getWeatherList().get(0).getDescription());
rise_time.setText(response.body().getSys().getSunrise() + " ");
set_time.setText(response.body().getSys().getSunset() + " ");
temp_out.setText(response.body().getMain().getTemp() + " ℃");
Press_out.setText(response.body().getMain().getPressure() + " hpa");
Humid_out.setText(response.body().getMain().getHumidity() + " %");
Ws_out.setText(response.body().getWind().getSpeed() + " Km/h");
Visi_out.setText(response.body().getVisibility() + " m");
Cloud_out.setText(response.body().getClouds().getAll()+ " %");
}
@Override
public void onFailure(@NotNull Call<Example> call, @NotNull Throwable t) {
t.printStackTrace();
}
});
}
}

另外，如果你想从你的片段访问你的活动小部件，你可以使用:

editText editText = getActivity().findViewById(R.id.textfield);
editText.getText().toString()