关于Android的一个程序问题，货币转换

============问题描述============


这是界面

这是界面的XML

package com.exercise2;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.view.inputmethod.EditorInfo;

import android.widget.*;

public class Currency extends Activity

{

private EditText cedit;

private Spinner cfrom;

private Spinner cto;

private Button cconvert;

private TextView ctext;

private Toast toast;

private ArrayAdapter<String> madapter1;

private ArrayAdapter<String> madapter2;

private String[] cdatafrom=

{

"-Please Select-",

"CNY","USD","GBP","EUR","JPY","HKD"

};

private String[] cdatato=

{

"-Please Select-",

"CNY","USD","GBP","EUR","JPY","HKD"

};

protected void onCreate(Bundle savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.currencyconverter);

cedit=(EditText)findViewById(R.id.edit2);

cconvert=(Button)findViewById(R.id.button3);

ctext=(TextView)findViewById(R.id.text5);

cfrom=(Spinner)findViewById(R.id.spinner1);

madapter1=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,cdatafrom);

madapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

cfrom.setAdapter(madapter1);

cto=(Spinner)findViewById(R.id.spinner2);

madapter2=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,cdatato);

madapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

cto.setAdapter(madapter2);

//cedit.setInputType(EditorInfo.TYPE_CLASS_PHONE);

cconvert.setOnClickListener(new OnClickListener()

{

public void onClick(View v)

{

// TODO Auto-generated method stub

String str=cedit.getText().toString();

double curr=Double.parseDouble(str);

while(!str.equalsIgnoreCase(""))

{

String from=cfrom.getSelectedItem().toString();

String to=cto.getSelectedItem().toString();

if(cfrom.getSelectedItem().toString().equalsIgnoreCase(cto.getSelectedItem().toString()))

{

ctext.setText("ssss");

//ctext.setText(str+" "+cfrom.getSelectedItem().toString());

}

else

{

if(cfrom.getSelectedItem().toString().equalsIgnoreCase("CNY"))

{

if(cto.getSelectedItem().toString().equalsIgnoreCase("USD"))

{

double curr1=curr*0.1631;

ctext.setText(curr1+" USD");

}

if(cto.getSelectedItem().toString().equalsIgnoreCase("GBP"))

{

double curr1=curr*0.1008;

ctext.setText(curr1+" GBP");

}

if(cto.getSelectedItem().toString().equalsIgnoreCase("EUR"))

{

double curr1=curr*0.1283;

ctext.setText(curr1+" EUR");

}

if(cto.getSelectedItem().toString().equalsIgnoreCase("JPY"))

{

double curr1=curr*17.5914;

ctext.setText(curr1+" JPY");

}

if(cto.getSelectedItem().toString().equalsIgnoreCase("HKD"))

{

double curr1=curr*1.2653;

ctext.setText(curr1+" HKD");

}

}

while(from=="USD")

{

if(to=="CNY")

{

double curr1=curr*6.1298;

ctext.setText(curr1+" "+to);

}

if(to=="GBP")

{

double curr1=curr*0.6179;

ctext.setText(curr1+" "+to);

}

if(to=="EUR")

{

double curr1=curr*0.7863;

ctext.setText(curr1+" "+to);

}

if(to=="JPY")

{

double curr1=curr*107.8320;

ctext.setText(curr1+" "+to);

}

if(to=="HKD")

{

double curr1=curr*7.7561;

ctext.setText(curr1+" "+to);

}

}

while(from=="GBP")

{

if(to=="CNY")

{

double curr1=curr*9.9204;

ctext.setText(curr1+" "+to);

}

if(to=="USD")

{

double curr1=curr*1.6184;

ctext.setText(curr1+" "+to);

}

if(to=="EUR")

{

double curr1=curr*1.2725;

ctext.setText(curr1+" "+to);

}

if(to=="JPY")

{

double curr1=curr*174.5137;

ctext.setText(curr1+" "+to);

}

if(to=="HKD")

{

double curr1=curr*12.5524;

ctext.setText(curr1+" "+to);

}

}

}

}

while(str.equalsIgnoreCase(""))

{

toast=Toast.makeText(Currency.this, "Enter The Value", Toast.LENGTH_SHORT);

toast.show();

}

}

});

}

}

这是部分代码

但是会有错，停止运行。。。


这是Logcat红色部分截图。

我自己想了很久，刚学水平有限啊。。

求大大帮忙看看

============解决方案1============

edit2在xml布局文件中没有定义，导致cedit对象为null

============解决方案2============

cedit=(EditText)findViewById(R.id.edit2);中R.id.edit2换成R.id.edit1就行了