如何在Android Studio中获得微调器值并将其传递给文本视图

Question

我在名称为（activity_add_comp）的活动中有一个名称为（@ + id / spinner）的微调框。我需要将微调器值传递给名称为（@ + id / district_id）的textView并抛出代码：“ params.put（” district_id“，district_id）;”。我的意思是将Spinner值设置为district_id而不是self。

我的Java代码是：

package com.cp.comp;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
public class add_comp extends AppCompatActivity {
    private EditText shop_name, complainant_name, complainant_id, mobile;
    private EditText  district_id, address_detail, comp_type, comp_detail;
    private ProgressBar loading;
    private static String URL_ADDCOMP = "http://172.23.50.55/CP/add_comp.php";
    private Button btn_add_comp;



ArrayList<String> listItems=new ArrayList<>();
ArrayAdapter<String> adapter;
Spinner sp;
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_add_comp);
    btn_add_comp = findViewById(R.id.btn_add_comp);
    loading = findViewById(R.id.loading);
    shop_name = findViewById(R.id.shop_name);
    complainant_name = findViewById(R.id.complainant_name);
    complainant_id = findViewById(R.id.complainant_id);
    mobile = findViewById(R.id.mobile);
    district_id = findViewById(R.id.district_id);
    address_detail = findViewById(R.id.address_detail);
    comp_type = findViewById(R.id.comp_type);
    comp_detail = findViewById(R.id.comp_detail);



   sp=(Spinner)findViewById(R.id.spinner);
    adapter=new ArrayAdapter<String>(this,R.layout.spinner_layout,R.id.txt,listItems);
    sp.setAdapter(adapter);


    btn_add_comp.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            Add_comp();
            }
    });
}
private void Add_comp() {
    loading.setVisibility(View.VISIBLE);
    btn_add_comp.setVisibility(View.GONE);
    final String shop_name        = this.shop_name.getText().toString().trim();
    final String complainant_name = this.complainant_name.getText().toString().trim();
    final String complainant_id   = this.complainant_id.getText().toString().trim();
    final String mobile           = this.mobile.getText().toString().trim();
    final String district_id      = this.district_id.getText().toString().trim();
    final String address_detail   = this.address_detail.getText().toString().trim();
    final String comp_type        = this.comp_type.getText().toString().trim();
    final String comp_detail      = this.comp_detail.getText().toString().trim();
    System.out.println("ya abed almoty");
    StringRequest stringRequest = new StringRequest(Request.Method.POST, URL_ADDCOMP,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    try{
                        JSONObject jsonObject = new JSONObject(response);
                        String success = jsonObject.getString("success");
                        System.out.println("ya habibi");
                        if (success.equals("1")) {
                            Toast.makeText(add_comp.this, "تم إرسال الشكوى بنجاح!", Toast.LENGTH_SHORT).show();
                            System.out.println("ya belal");
                        }


                    } catch (JSONException e) {
                        e.printStackTrace();
                        Toast.makeText(add_comp.this, "ارسال خاطئ! " + e.toString(), Toast.LENGTH_SHORT).show();
                        loading.setVisibility(View.GONE);
                        btn_add_comp.setVisibility(View.VISIBLE);
                        System.out.println("ya jehad");
                    }
                }
            },
            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Toast.makeText(add_comp.this, "ارسال خاطئ! " + error.toString(), Toast.LENGTH_SHORT).show();
                    loading.setVisibility(View.GONE);
                    btn_add_comp.setVisibility(View.VISIBLE);
                    System.out.println("ya morad");
                }
            })

    {
        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            Map<String, String> params = new HashMap<>();
            params.put("shop_name", shop_name);
            params.put("complainant_name", complainant_name);
            params.put("complainant_id", complainant_id);
            params.put("mobile", mobile);
            params.put("district_id", district_id);
            params.put("address_detail", address_detail);
            params.put("comp_type", comp_type);
            params.put("comp_detail", comp_detail);


            System.out.println("ya fahed" +  params.put("comp_type", comp_type));
            return params;
        }
    };
    RequestQueue requestQueue = Volley.newRequestQueue(this);
    requestQueue.add(stringRequest);
}
public void onStart(){
    super.onStart();
    add_comp.BackTask bt=new add_comp.BackTask();
    bt.execute();
}
private class BackTask extends AsyncTask<Void,Void,Void> {
    ArrayList<String> list;
    protected void onPreExecute(){
        super.onPreExecute();
        list=new ArrayList<>();

    }
    protected Void doInBackground(Void...params){
        InputStream is=null;
        String result="";
        try{
            HttpClient httpclient=new DefaultHttpClient();
            HttpPost httppost= new HttpPost("http://172.23.50.55/CP/select_district_name.php");
            HttpResponse response=httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            // Get our response as a String.
            is = entity.getContent();
        }catch(IOException e){
            e.printStackTrace();
        }
        //convert response to string
        try{
            BufferedReader reader = new BufferedReader(new InputStreamReader(is,"utf-8"));
            String line = null;
            while ((line = reader.readLine()) != null) {
                result+=line;
            }
            is.close();
            //result=sb.toString();
        }catch(Exception e){
            e.printStackTrace();
        }
        // parse json data
        try{
            JSONArray jArray =new JSONArray(result);
            for(int i=0;i<jArray.length();i++){
                JSONObject jsonObject=jArray.getJSONObject(i);
                // add interviewee name to arraylist
                list.add(jsonObject.getString("dis_name"));
                System.out.println("rtrtrt" + jsonObject);
            }
        }
        catch(JSONException e){
            e.printStackTrace();
        }
        return null;
    }
    protected void onPostExecute(Void result){
        listItems.addAll(list);
        adapter.notifyDataSetChanged();
    }
}
}

activity_add_comp.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingLeft="30dp"
    android:paddingTop="80dp"
    android:paddingRight="30dp"
    tools:context="com.cp.comp.add_comp">
    <EditText
        android:id="@+id/shop_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="اسم المحل"
        android:inputType="textPersonName"
        android:textColor="@color/colorText" />
    <EditText
        android:id="@+id/complainant_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:hint="اسم المشتكي"
        android:inputType="textPersonName"
        android:textColor="@color/colorText" />
    <EditText
        android:id="@+id/complainant_id"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="هوية المشتكي"
        android:inputType="textPersonName"
        android:textColor="@color/colorText" />
    <EditText
        android:id="@+id/mobile"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:hint="موبايل المشتكي"
        android:inputType="number"
        android:digits="0123456789"
    android:textColor="@color/colorText" />
<EditText
    android:id="@+id/address_detail"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:hint="عنوان المحل التفصيلي"
    android:inputType="textPersonName"
    android:textColor="@color/colorText" />
<EditText
    android:id="@+id/comp_type"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="طبيعة الشكوى"
    android:inputType="textPersonName"

    android:textColor="@color/colorText" />
<EditText
    android:id="@+id/comp_detail"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:hint="تفصيل الشكوى"
    android:inputType="textPersonName"
    android:textColor="@color/colorText" />
<ProgressBar
    android:id="@+id/loading"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="30dp"
    android:visibility="gone" />
<EditText
    android:id="@+id/district_id"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="المحافظة"
    android:inputType="textPersonName"
    android:textColor="@color/colorText" />

<Spinner
    android:id="@+id/spinner"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="10dp" />
<Button
    android:id="@+id/btn_add_comp"
    android:layout_width="match_parent"
    android:layout_height="55dp"
    android:layout_marginTop="30dp"
    android:backgroundTint="@color/colorPrimaryDark2"
    android:text="ارسال"
    android:textColor="@android:color/white" />
</LinearLayout>

spinner_layout.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
    <TextView
        android:id="@+id/txt"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        />
</LinearLayout>

Answer 1

import React, { useState } from 'react';

const Main = props => {
  const [state, setState] = useState({
    noteArray: [],
    noteText: '',
  });


  const addNote = () => {
    if(state.noteText){
      var d = new Date();
      let x = {
        'date': d.getFullYear() + 
        "/" + (d.getMonth() + 1 ) +
        "/" + d.getDate(),
        'note': state.noteText
      }

      setState({...state, noteArray: [...state.noteArray, x]});

      console.log(state.noteArray);
    }
  }

   .......................the rest of code
}

OR

String text = mySpinner.getSelectedItem().toString();
editText.setText(text);

Answer 2

    public class add_comp extends AppCompatActivity {

    //String will be fetched from spinner
    String spinnerText;
    //Your spinner
    Spinner sp;
    //Your edittext
    TextView textview;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_add_comp);

    //This will do exactly what you need by getting the selected item string for you
    spinnerText = sp.getSelectedItem().toString();

    //This will pass the selected string into your edittext
    textview.setText(spinnerText);


    }
}

Answer 3

先生，它给了我这样的错误： java.lang.NullPointerException：尝试在com.cp.comp.add_comp.Add_comp（add_comp.java:114）上的空对象引用上调用虚拟方法'void android.widget.TextView.setText（java.lang.CharSequence）' 请在您的代码中记录我的评论

public class add_comp extends AppCompatActivity {
//String will be fetched from spinner
String spinnerText;
//Your spinner
Spinner sp;
//Your edittext
TextView textview;

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_add_comp);

//This will do exactly what you need by getting the selected item string for you
spinnerText = sp.getSelectedItem().toString();   My comment: here is the error

//This will pass the selected string into your edittext
textview.setText(spinnerText);


}
}

Answer 4

首先使用类实现ONItemClickListner，然后覆盖  public void onItemSelected(AdapterView<?> arg0, View arg1, int position, long id)，然后选择值后，将在方法getApplicationContext(),data[position]中获得结果

这是mainactivity的代码

 spin.setOnItemSelectedListener(this);  

    //Creating the ArrayAdapter instance having the country list  
    ArrayAdapter aa = new ArrayAdapter(this,android.R.layout.simple_spinner_item,country);  
    aa.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);  
    //Setting the ArrayAdapter data on the Spinner  
    spin.setAdapter(aa);