基本上这是代码结构，我想知道如何修改我的代码，以便我可以在onResponse中获取值并返回它。截至目前，我的mainReply变量返回＆＃34;（空白）＆＃34;但是我希望它能在我的onResponse段中传递名为细节的arraylist中的数据。请放心，我已经检查了返回的值，但我无法将值传递出onResponse段。
我已经检查了替代品，他们提到使用界面。但是，我不知道如何修改我的代码以使用提到的接口和使用callBacks的解决方案。
Joke答案 0 :(得分：1)
如果你想修改你现有的代码，你可以添加一个类似于我加入的界面（RevealDetailsCallbacks），将其传递给asynctask构造函数，然后运行它。代码如下所示：
public class MainActivity extends AppCompatActivity {
//Interface callback here
interface RevealDetailsCallbacks {
public void getDataFromResult(List<String> details);
}
EditText et_message;
FloatingActionButton fab_send;
API api;
ListView list_view_conversation;
List<ChatModel> list_chat = new ArrayList<>();
RevealDetailsCallbacks callback;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
et_message = (EditText) findViewById(R.id.et_message);
fab_send = (FloatingActionButton) findViewById(R.id.fab_send);
list_view_conversation = (ListView) findViewById(R.id.list_view_conversation);
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(API.BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
this.callback = new RevealDetailsCallbacks() {
@Override
public void getDataFromResult(List<String> details) {
//Do stuff here with the returned list of Strings
}
};
api = retrofit.create(API.class);
fab_send.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//this method ultimately is to get response and send back to user
String s = et_message.getText().toString();
ChatModel model = new ChatModel(s, true);
list_chat.add(model);
new retrieveDetails(callback).execute(list_chat);
et_message.setText("'");
}
});
}
public class retrieveDetails extends AsyncTask<List<ChatModel>, Void, String> {
String text = et_message.getText().toString();
String mainReply = "";
List<ChatModel> models;
List<String> details = new ArrayList<String>();
private RevealDetailsCallbacks listener;
retrieveDetails(RevealDetailsCallbacks listener){
this.listener = listener;
}
@Override
public String doInBackground(final List<ChatModel>[] lists) {
Call<List<Patient>> call = api.getPatients();
models = lists[0];
call.enqueue(new Callback<List<Patient>>() {
public String reply;
@Override
public void onResponse(Call<List<Patient>> call, Response<List<Patient>> response) {
List<Patient> patients = response.body();
for (int i = 0; i < patients.size(); i++) {
if (patients.get(i).getNric().equals(text)) {
details.add("Name: " + patients.get(i).getName() + "\nNRIC: " + patients.get(i).getNric()
+ "\nDOB: " + patients.get(i).getDob() + "\nContact No: " + patients.get(i).getContactno());
}
}
this.mainReply = details.get(0);
Log.i("Here Log i", reply);
if(listener != null) {
listener.getDataFromResult(details);
}
}
@Override
public void onFailure(Call<List<Patient>> call, Throwable t) {
//Don't make a toast here, it will throw an exception due to it being in doInBackground
//Toast.makeText(getApplicationContext(), t.getMessage(), Toast.LENGTH_SHORT).show();
}
});
return mainReply;//I want to reply with the data added into the details arraylist in the onResponse segment
}
@Override
public void onPostExecute(String s) {
ChatModel chatModel = new ChatModel(s, false);
models.add(chatModel);
CustomAdapter adapter = new CustomAdapter(models, getApplicationContext());
list_view_conversation.setAdapter(adapter);
}
}
}
但是，这里不需要asynctask，因为你正在运行Retrofit并调用.enqueue，它运行在后台线程上。一个更简单的版本看起来像这样：
public class MainActivity extends AppCompatActivity {
//Interface callback here
interface RevealDetailsCallbacks {
public void getDataFromResult(List<String> details);
}
//Keep your same variables here
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Same setup here
this.callback = new RevealDetailsCallbacks() {
@Override
public void getDataFromResult(List<String> details) {
//Do stuff here with the returned list of Strings
}
};
fab_send.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//Same setup here, then call the method
makeWebCalls();
}
});
}
private void makeWebCalls(){
Call<List<Patient>> call = api.getPatients();
models = lists[0];
call.enqueue(new Callback<List<Patient>>() {
@Override
public void onResponse(Call<List<Patient>> call, Response<List<Patient>> response) {
//Run your response code here. When done, pass to the callback
}
@Override
public void onFailure(Call<List<Patient>> call, Throwable t) {
Toast.makeText(getApplicationContext(), t.getMessage(), Toast.LENGTH_SHORT).show();
}
});
}
}
答案 1 :(得分：0)
您可以立即在OnClick中将Retrofit呼叫排入队列，并在那里处理其响应
return this.esriLoader.load({
url: 'https://js.arcgis.com/4.6/'
}).then(() => {
return this.esriLoader.loadModules([
'esri/Map', 'esri/views/MapView', 'esri/layers/GraphicsLayer', 'esri/layers/FeatureLayer', "esri/tasks/Geoprocessor",
"esri/tasks/support/FeatureSet", "esri/Graphic","esri/geometry/Point"
]).then(([
Map, MapView, GraphicsLayer, FeatureLayer, Geoprocessor, FeatureSet, Graphic,PointObj
]) => {
//this is where the object comes from that allows me to say
//new this._mapDependencies.FeatureLayer() or Point() etc
//once again, new Point() works, but FeatureLayer() does not,
//even though both objects are filled
return {
Geoprocessor: Geoprocessor,
Graphic: Graphic,
GraphicsLayer: GraphicsLayer,
FeatureLayer: FeatureLayer,
FeatureSet: FeatureSet,
Point:PointObj
}
});
});