我正在尝试更改一个编辑视图的值，而另一个编辑视图中有更改，即使程序运行值未传递给编辑视图。值从一个编辑视图传递到另一个编辑视图，然后该值乘以解析值。帮助我的主要活动代码是：
public class Main extends ListActivity {
public double C_webuserDouble;
public double C_cashDouble;
public double C_transferDouble;
public double S_webuserDouble;
public double S_cashDouble;
public double S_transferDouble;
EditText resultTxt ;
TextView cashTxtView ;
TextView webuserTxtView;
TextView transferTxtView;
TextView S_cashTxtView ;
TextView S_webuserTxtView;
TextView S_transferTxtView;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listplaceholder);
ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
JSONObject json = JSONfunctions.getJSONfromURL("http://ldsclient.com/ftp/strtojson.php");
try{
JSONArray netfoxlimited = json.getJSONArray("netfoxlimited");
for(int i=0;i<netfoxlimited.length();i++){
HashMap<String, String> map = new HashMap<String, String>();
JSONObject e = netfoxlimited.getJSONObject(i);
map.put("date", e.getString("date"));
map.put("c_web", e.getString("c_web"));
map.put("c_bank",e.getString("c_bank"));
map.put("c_cash", e.getString("c_cash"));
map.put("s_web", e.getString("s_web"));
map.put("s_bank",e.getString("s_bank"));
map.put("s_cash", e.getString("s_cash"));
mylist.add(map);
/** C_webuserDouble=json.getDouble("c_web");
C_transferDouble= json.getDouble("c_bank");
C_cashDouble=json.getDouble("c_cash");
S_webuserDouble=json.getDouble("s_web");
S_transferDouble= json.getDouble("s_bank");
S_cashDouble=json.getDouble("s_cash");*/
}
}catch(JSONException e) {
Log.e("log_tag", "Error parsing data "+e.toString());
}
ListAdapter adapter = new SimpleAdapter(this, mylist , R.layout.main,
new String[] {"date", "c_web" ,"c_bank","c_cash","s_web" ,"s_bank","s_cash",},
new int[] { R.id.item_title,R.id.webuserTxtView, R.id.transferTxtView, R.id.cashTxtView, R.id.S_webuserTxtView, R.id.S_transferTxtView, R.id.S_cashTxtView});
setListAdapter(adapter);
resultTxt = (EditText) findViewById(R.id.editText1);
resultTxt.addTextChangedListener(new TextWatcher(){
public void afterTextChanged(Editable arg0) {
// TODO Auto-generated method stub
String text;
text=resultTxt.getText().toString();
if(resultTxt.getText().length()>0){
calculateSum(C_webuserDouble,C_cashDouble,C_transferDouble);
calculateSunrise(S_webuserDouble,S_cashDouble,S_transferDouble);
}
}
public void beforeTextChanged(CharSequence arg0, int arg1,
int arg2, int arg3) {
// TODO Auto-generated method stub
}
public void onTextChanged(CharSequence s, int start, int before,
int count) {
// TODO Auto-generated method stub
}});}
private void calculateSum(Double webuserDouble, Double cashDouble, Double transferDouble){
String Qty;
Qty= resultTxt.getText().toString();
if(Qty.length() >0){
double QtyValue = Double.parseDouble(Qty);
double cashResult;
double webuserResult;
double transferResult;
cashResult = cashDouble * QtyValue;
webuserResult = webuserDouble * QtyValue;
transferResult = transferDouble * QtyValue;
DecimalFormat df = new DecimalFormat("#.##");
String cashResultStr = df.format(cashResult);
String webuserResultStr = df.format(webuserResult);
String transferResultStr = df.format(transferResult);
cashTxtView.setText(String.valueOf(cashResultStr));
webuserTxtView.setText(String.valueOf(webuserResultStr));
transferTxtView.setText(String.valueOf(transferResultStr));
//cashTxtView.setFilters(new InputFilter[] {new DecimalDigitsInputFilter(2)});
}
if(Qty.length()==0){
cashTxtView.setText(String.valueOf(cashDouble));
webuserTxtView.setText(String.valueOf(webuserDouble));
transferTxtView.setText(String.valueOf(transferDouble));
}
}
private void calculateSunrise(Double webuserDouble, Double cashDouble, Double transferDouble){
String Qty;
Qty= resultTxt.getText().toString();
if(Qty.length() >0){
double QtyValue = Double.parseDouble(Qty);
double cashResult;
double webuserResult;
double transferResult;
cashResult = cashDouble * QtyValue;
webuserResult = webuserDouble * QtyValue;
transferResult = transferDouble * QtyValue;
DecimalFormat df = new DecimalFormat("#.##");
String cashResultStr = df.format(cashResult);
String webuserResultStr = df.format(webuserResult);
String transferResultStr = df.format(transferResult);
S_cashTxtView.setText(String.valueOf(cashResultStr));
S_webuserTxtView.setText(String.valueOf(webuserResultStr));
S_transferTxtView.setText(String.valueOf(transferResultStr));
}
if(Qty.length()==0){
S_cashTxtView.setText(String.valueOf(cashDouble));
S_webuserTxtView.setText(String.valueOf(webuserDouble));
S_transferTxtView.setText(String.valueOf(transferDouble));
}
}
}
以下是我的列表占位符代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="@id/android:list"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:drawSelectorOnTop="false" />
<TextView
android:id="@id/android:empty"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="No data"/>
</LinearLayout>
所有代码都相同，但在给出用户输入时会生成以下 logcat 错误
08-29 14:53:01.234: E/AndroidRuntime(2206): Uncaught handler: thread main exiting due to uncaught exception
08-29 14:53:01.245: E/AndroidRuntime(2206): java.lang.NullPointerException
08-29 14:53:01.245: E/AndroidRuntime(2206): at com.mokshya.jsonnetfoxtab.Main.calculateSum(Main.java:142)
08-29 14:53:01.245: E/AndroidRuntime(2206): at com.mokshya.jsonnetfoxtab.Main.access$0(Main.java:120)
08-29 14:53:01.245: E/AndroidRuntime(2206): at com.mokshya.jsonnetfoxtab.Main$1.afterTextChanged(Main.java:101)