用Spinner将EditText值相乘

Question

我目前正在为学校开发货币换算器项目。 我有货币（美元，欧元等）和数值（6.54,9.56等）的阵列。

我有两个微调器和一个EditText，你可以选择从一个微调器中的单元和另一个微调器中的单元。然后它应该考虑editText中的数量并在textView中显示“实时”结果。如果你改变spinners或editText，textview中的值应该直接更新。

比方说，插在EDITTEXT值是10.0，我们希望把它从美元到欧元转换，计算将是这样的：10.0 * 6.54/9.56 =

但我想不出如何将editText添加到计算中，现在只会将spinner1中的值添加到spinner2中的值中。

这里是strings.mxl

<resources> 
<string name="app_name">CurrencyConverter3</string> 
<string name="menu_settings">Settings</string> 
<string name="title_activity_main">Dinner Time</string> 
<string name="textView1Text">From:</string> 
<string name="textView2Text">To:</string> 
<string name="textView3Text">Amount:</string> 
<string name="textView4Text">Amount:</string> 
<string-array name="currency"> 
    <item >Choose currency</item> 
    <item >AUD</item> 
    <item >USD</item> 
    <item >SEK</item> 
    <item >EUR</item> 
    <item >YEN</item> 
</string-array> 
<string-array name="price"> 
    <item >0</item> 
    <item >6.91</item> 
    <item >6.54</item> 
    <item >1.00</item> 
    <item >9.56</item> 
    <item >0.0837</item> 
</string-array> 

这里是mainactivity.java

package com.example.xxx.currencyconverter; 

import android.app.Activity; 
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 android.widget.EditText; 

public class MainActivity extends Activity { 
    private String [] currency; 
    private ArrayAdapter<String> adapter; 
    private Spinner spin1, spin2; 
    private EditText amount; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     setUpTheSpinners(); 

    } 


    private void setUpTheSpinners() { 
     currency = getResources().getStringArray(R.array.currency); 
     adapter= new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, currency); 
     adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); 
     AdapterView.OnItemSelectedListener listener = new currencySelectedListener(); 
     spin1 = (Spinner)findViewById(R.id.spinner1); 
     spin1.setAdapter(adapter); 
     spin1.setOnItemSelectedListener(listener); 
     spin2 = (Spinner)findViewById(R.id.spinner2); 
     spin2.setAdapter(adapter); 
     spin2.setOnItemSelectedListener(listener); 
    } 

    private void calculateSum() { 
     String [] price = getResources().getStringArray(R.array.price); 
     int index1 = spin1.getSelectedItemPosition(); 
     int index2 = spin2.getSelectedItemPosition(); 
     double cost1 = Double.parseDouble(price[index1]); 
     double cost2 = Double.parseDouble(price[index2]); 
     double totalCost = cost1 + cost2; 
     TextView totalCostText = (TextView)findViewById(R.id.textView5); 
     totalCostText.setText("" + totalCost); 
    } 



private class currencySelectedListener implements AdapterView.OnItemSelectedListener { 
    public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) { 
     calculateSum(); 

    } 

     public void onNothingSelected(AdapterView<?> parent) { 
     } 
    } 
} 

谢谢配合“的EditText

Answer 1

1. 获得当前编辑的文本值。 getText（）。toString（）“
2. 解析字符串为双
3. 乘法与汇率
4. 解析输出字符串

5. 集编辑文本值的输出u从第4步得到

   private void convert() { 
       String [] price = getResources().getStringArray(R.array.price); 
       int index = spinner.getSelectedItemPosition(); 
       double curr_ratio = Double.parseDouble(price[index]); 
   
       EditText et_value = (EditText)findViewById(R.id.edit_text); 
       double value = Double.parseDouble(et_value.getText().toString()); 
       et_value.setText(String.valuOf(value*curr_ratio)); 
   }