Question

我已经在这里待了一个多小时，现在正在阅读相关问题，但还没有找到解决方案来解决我的问题，所以我会问。

我有一个旋转器。我想在该微调器中使用所选城市来设置纬度和经度变量。我无法弄清楚如何直接调用该信息，或者在单击“使用此城市”按钮时将其设置为变量。这是我到目前为止的代码。

的strings.xml

<string-array name="locations">
    <item > Washington D.C. </item>      
    <item >New York, NY</item> 
    <item >Juneau, AL</item>
    </string-array>

MainActivity.java

    package cl.telematica.locationexample;

   import      cl.telematica.locationexample.interfaces.LocationListenerHandler;
   import cl.telematica.locationexample.location.ActiveLocationManagerActivity;


    import android.content.Intent;
    import android.location.Location;
    import android.os.Bundle;
    import android.view.Menu;
    import android.view.View;
import android.view.WindowManager;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends ActiveLocationManagerActivity {

    public static String citylatitudText;
    public static String citylongitudText;
    public static TextView latitudText;
    public static TextView longitudText;
    public static String locationSet;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

        /*ArrayAdapter<String> adapter;
        locationSet = getResources().getStringArray(R.array.locations);
        adapter = new ArrayAdapter<String>(
                this,
                android.R.layout.simple_list_item_1,
                locationSet);

         setListAdapter(adapter);*/
        Button b = (Button)findViewById(R.id.btnTestNoResults);
    Button c = (Button)findViewById(R.id.btnGPSSearch);
    Button d = (Button)findViewById(R.id.btnSetCity);

    final Spinner spinner = (Spinner)findViewById(R.id.spinner1);
    ArrayAdapter<CharSequence> location_adapter = ArrayAdapter.createFromResource(this, R.array.locations, android.R.layout.simple_spinner_item);
    location_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner.setAdapter(location_adapter);

    //final String locationSet = spinner.getSelectedItem().toString();
    //final String locationSet = spinner.getItemAtPosition(spinner.getSelectedItemPosition()).toString();
   // spinner.setSelection(((ArrayAdapter<String>)spinner.getAdapter()).getPosition(locationSet));

    //final String locationSet = (String) spinner.getSelectedItem();
    b.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                startActivity(new Intent(MainActivity.this, NoResults.class));
            };
        });
        c.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                //if ()
                // TODO Auto-generated method stub
                startActivity(new Intent(MainActivity.this, NewSearch.class));
            };
        });

        d.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                if( locationSet == "Washington D.C.")
                { citylatitudText = "38.9047 N";
                citylongitudText = "77.0164 W";
                }

                else if (locationSet == "New York, NY")
                {citylatitudText = "40.7127° N";
                citylongitudText = "74.0059° W";            
                }
                else
                {citylatitudText = "58.3000° N";
                citylongitudText = "134.4167° W";           
                }

                // TODO Auto-generated method stub
                startActivity(new Intent(MainActivity.this, NewSearch.class));
            };
        });
        latitudText = (TextView) findViewById(R.id.textView4);
        longitudText = (TextView) findViewById(R.id.textView5);

        listener = new LocationListenerHandler() {
            @Override
            public void OnLocationReceived(Location loc) {
                latitudText.setText("" + loc.getLatitude());
                longitudText.setText("" + loc.getLongitude());
            }
        };
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

NewSearch.java

package cl.telematica.locationexample;

import android.os.Bundle;
import android.widget.TextView;
import cl.telematica.locationexample.location.ActiveLocationManagerActivity;

public class NewSearch extends ActiveLocationManagerActivity {

    public TextView citylat;
    public TextView citylong;
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_new_search);
        citylat = (TextView) findViewById(R.id.textView4);
        citylong = (TextView) findViewById(R.id.textView5);
        citylat.setText(""+ MainActivity.citylatitudText);
        //citylong.setText("" + MainActivity.citylongitudText);
        citylong.setText("" + MainActivity.locationSet);//testing to see if the city name selected by spinner is being put in variable form


    }

}

当我点击“使用此城市”按钮时，我在NewSearch页面上获取citylong变量的单词“null”，并为citylat获取“58.3000°N”（因此它将转到“else” “声明，无论我选择哪个城市）。

我知道还有其他一些关于从Spinner调用的帖子，你可以看到我在哪里尝试了一些并将它们留在我的代码中注释掉，因为它们没有用。

我感谢您提供的任何帮助。

Answer 1

在比较字符串时，您可以尝试使用equals方法吗？

docker commit

单击按钮后尝试从微调器获取字符串值。包括

    if( locationSet.equals("Washington D.C."))

中的

    final String locationSet = (String) spinner.getSelectedItem();

方法。我遇到过类似的问题，这些黑客帮助我解决了这个问题。如果您在模拟器上运行，则可能会遇到一些延迟/进程问题，因此请在移动设备上安装它。

如果这有帮助，请告诉我。

更新1：

这可能是完全错误的，但这就是我实现Spinner的方式。

首先使用数组适配器更新和设置Spinner中的项目并告诉代码它们是什么。所以，要在你的代码中做到这一点
```
     d.setOnClickListener(new OnClickListener() {
```

我在你的代码中发现了这个缺失。我想这应该有用。

Answer 2

我终于开始工作了。这是我现在的代码（工作！耶！）

MainActivity.java

import android.content.Intent;
import android.location.Location;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.WindowManager;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends ActiveLocationManagerActivity {

    public static String citylatitudText;
    public static String citylongitudText;
    public static TextView latitudText;
    public static TextView longitudText;
    public static String locationSet;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

        Button b = (Button)findViewById(R.id.btnTestNoResults);
        Button c = (Button)findViewById(R.id.btnGPSSearch);
        Button d = (Button)findViewById(R.id.btnSetCity);

        final Spinner spinner = (Spinner)findViewById(R.id.spinner1);
        ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item);
        dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setOnItemSelectedListener(new CustomOnItemSelectedListener());

        b.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {           
                startActivity(new Intent(MainActivity.this, NoResults.class));
            };
        });
        c.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {           
                startActivity(new Intent(MainActivity.this, NewSearch.class));
            };
        });

        d.setOnClickListener(new OnClickListener() {


            @Override
            public void onClick(View v) {

                String locationSet = String.valueOf(spinner.getSelectedItem());
                if( locationSet.equals("Washington D.C.") )
                { citylatitudText = "38.9047 N";
                citylongitudText = "77.0164 W";
                }
                else if (locationSet.equals("Mansfield, PA"))
                {citylatitudText = "41.8061 N";
                citylongitudText = "77.0756 W";         
                }
                else if (locationSet.equals( "New York, NY"))
                {citylatitudText = "40.7127° N";
                citylongitudText = "74.0059° W";            
                }
                else if (locationSet.equals( "Juneau, AL"))
                {citylatitudText = "58.3000° N";
                citylongitudText = "134.4167° W";           
                }
                else if (locationSet.equals("Phoenix, AZ"))
                {citylatitudText = "33.4500° N";
                citylongitudText = "112.0667° W";           
                }
                else if (locationSet.equals("Tucson, AZ"))
                {citylatitudText = "32.2217° N";
                citylongitudText = "110.9264° W";           
                }
                else if (locationSet.equals( "Sacramento, CA"))
                {citylatitudText = "38.5556° N";
                citylongitudText = "121.4689° W";           
                }
                else if (locationSet.equals("San Diego, CA"))
                {citylatitudText = "32.7150° N";
                citylongitudText = "117.1625° W";           
                }
                else if (locationSet.equals("Los Angeles, CA"))
                {citylatitudText = "34.0500° N";
                citylongitudText = "118.2500° W";           
                }
                else if (locationSet.equals("Denver, CO"))
                {citylatitudText = "39.7392° N";
                citylongitudText = "104.9903° W";           
                }
                else if (locationSet.equals("Jacksonville, FL"))
                {citylatitudText = "30.3369° N";
                citylongitudText = "81.6614° W";            
                }
                else if (locationSet.equals("Orlando, FL"))
                {citylatitudText = "28.4158° N";
                citylongitudText = "81.2989° W";            
                }
                else if (locationSet.equals("Atlanta, GA"))
                {citylatitudText = "33.7550° N";
                citylongitudText = "84.3900° W";            
                }
                else if (locationSet.equals("Boise, ID"))
                {citylatitudText = "43.6167° N";
                citylongitudText = "116.2000° W";           
                }
                else if (locationSet.equals("Chicago, IL"))
                {citylatitudText = "41.8369° N";
                citylongitudText = "87.6847° W";            
                }
                else if (locationSet.equals("Indianapolis, IN"))
                {citylatitudText = "39.7910° N";
                citylongitudText = "86.1480° W";            
                }
                else if (locationSet.equals("Des Moines, IA"))
                {citylatitudText = "41.5908° N";
                citylongitudText = "93.6208° W";            
                }
                else if (locationSet.equals("Kansas City, KS"))
                {citylatitudText = "39.1067° N";
                citylongitudText = "94.6764° W";            
                }
                else if (locationSet.equals("Louisville, KY"))
                {citylatitudText = "38.2500° N";
                citylongitudText = "85.7667° W";            
                }
                else if (locationSet.equals("New Orleans, LA"))
                {citylatitudText = "29.9500° N";
                citylongitudText = "90.0667° W";            
                }
                else if (locationSet.equals("Portland, ME"))
                {citylatitudText = "43.6667° N";
                citylongitudText = "70.2667° W";            
                }
                else if (locationSet.equals("Baltimore, MD"))
                {citylatitudText = "39.2833° N";
                citylongitudText = "76.6167° W";            
                }
                else if (locationSet.equals("Boston, MA"))
                {citylatitudText = "42.3601° N";
                citylongitudText = "71.0589° W";            
                }
                else if (locationSet.equals("Detroit, MI"))
                {citylatitudText = "42.3314° N";
                citylongitudText = "83.0458° W";            
                }
                else if (locationSet.equals("Minneapolis, MN"))
                {citylatitudText = "44.9778° N";
                citylongitudText = "93.2650° W";            
                }
                else if (locationSet.equals("Seattle, WA"))
                {citylatitudText = "47.6097° N";
                citylongitudText = "122.3331° W";           
                }
                else
                {citylatitudText = "39.9500° N";
                citylongitudText = "75.1667° W";            
                }               
                // TODO Auto-generated method stub
                startActivity(new Intent(MainActivity.this, NewSearch.class));
            };
        });
        latitudText = (TextView) findViewById(R.id.textView4);
        longitudText = (TextView) findViewById(R.id.textView5);

        listener = new LocationListenerHandler() {
            @Override
            public void OnLocationReceived(Location loc) {
                latitudText.setText("" + loc.getLatitude());
                longitudText.setText("" + loc.getLongitude());
            }
        };
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

无法确定微调器值

2 个答案: