如何使用微調項目作爲輸入獲得結果

Question

我是新來的android。我正在構建一個城市公交車票的應用程序。我會用兩個紡紗廠作爲'起點'和'目的地'。我想匹配這兩個輸入，並在textview中將結果作爲「票價」。請給我一些關於如何實現這一點的簡單想法。

（）返回其選擇的對象或spinner.getSelectedItemPosition（）將返回選定的項目位置，並根據雙方的選擇

Answer 1

使用spinner.getSelectedItem微調器，你會計算你車費

Answer 2

這裏是工作示例：

activity_main.xml中：

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:orientation="vertical" 
    android:padding="24dp"> 

    <TextView 
     android:id="@+id/text_result" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_gravity="center_horizontal" 
     android:textSize="30dp" 
     android:text="RESULT"/> 

    <Spinner 
     android:id="@+id/spinner_source" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_marginTop="16dp"> 

    </Spinner> 

    <Spinner 
     android:id="@+id/spinner_destination" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_marginTop="16dp"> 

    </Spinner> 

</LinearLayout> 

MainActivity.ja VA

import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.ArrayAdapter; 
import android.widget.Spinner; 
import android.widget.TextView; 

import java.util.ArrayList; 
import java.util.List; 

public class MainActivity extends AppCompatActivity { 

    TextView textResult; 
    Spinner spinnerSource; 
    Spinner spinnerDestination; 

    String source; 
    String destination; 
    int cost = 0; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     // Views 
     textResult = (TextView) findViewById(R.id.text_result); 
     spinnerSource = (Spinner) findViewById(R.id.spinner_source); 
     spinnerDestination = (Spinner) findViewById(R.id.spinner_destination); 

     // Spinner Drop down elements 
     List<String> locations = new ArrayList<String>(); 
     locations.add("Location 1"); 
     locations.add("Location 2"); 
     locations.add("Location 3"); 

     // Initialize 
     source = locations.get(0); 
     destination = locations.get(0); 

     // Creating adapter for spinner 
     ArrayAdapter<String> adapterSpinnerSource = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, locations); 
     ArrayAdapter<String> adapterSpinnerDestination = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, locations); 

     // attaching data adapter to spinners 
     spinnerSource.setAdapter(adapterSpinnerSource); 
     spinnerDestination.setAdapter(adapterSpinnerDestination); 

     // Spinner item select listener 
     spinnerSource.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
      @Override 
      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 

       // Source location 
       source = parent.getItemAtPosition(position).toString(); 

       calculateCost(); 
      } 

      @Override 
      public void onNothingSelected(AdapterView<?> parent) { 

      } 
     }); 

     spinnerDestination.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
      @Override 
      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 

       // Destination location 
       destination = parent.getItemAtPosition(position).toString(); 

       calculateCost(); 
      } 

      @Override 
      public void onNothingSelected(AdapterView<?> parent) { 

      } 
     }); 
    } 

    public void calculateCost() { 

     if ((source.equals("Location 1") && destination.equals("Location 2")) 
       || (source.equals("Location 2") && destination.equals("Location 1"))) { 

      cost = 100; 
     } else if ((source.equals("Location 1") && destination.equals("Location 3")) 
       || (source.equals("Location 3") && destination.equals("Location 1"))) { 

      cost = 200; 
     } else if ((source.equals("Location 2") && destination.equals("Location 3")) 
       || (source.equals("Location 3") && destination.equals("Location 2"))) { 

      cost = 300; 
     } 

     // Output 
     textResult.setText(String.valueOf(cost)); 
    } 
} 

OUTPUT：

希望這將有助於〜