我在Android上进行计算，它将在文本视图中显示。
current odometer(edit text) - previous odometer(edit text) / number of fuel pump.
我在我的代码中做过类似的事情，但它似乎没有用。 每当我想将之前的里程表（编辑文本）更改为其他值时， 文本视图将显示-infinity。
我想知道为什么会这样。 我希望我已经足够清楚了。
有人能帮助我吗？
这是我的代码：
odometerEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
//here, after we introduced something in the EditText we get the string from it
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase(""))
odmEditStr = odometerEdit.getText().toString().trim();
if(!odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
preOdm = odometerPreEdit.getText().toString().trim();
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase("") && !pumpEdit.getText().toString().trim().equalsIgnoreCase("") && !odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
{
resultCon = Double.parseDouble(odmEditStr) - Double.parseDouble(preOdm) / Double.parseDouble(pumpEditStr);
fconView.setText(" "+resultCon);
}
}
});
odometerPreEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
//here, after we introduced something in the EditText we get the string from it
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase(""))
odmEditStr = odometerEdit.getText().toString().trim();
if(!odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
preOdm = odometerPreEdit.getText().toString().trim();
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase("") && !pumpEdit.getText().toString().trim().equalsIgnoreCase("") && !odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
{
resultCon = Double.parseDouble(odmEditStr) - Double.parseDouble(preOdm) / Double.parseDouble(pumpEditStr);
fconView.setText(" "+resultCon);
}
}
});
这是我的完整源代码：
public class updateAnddelete extends Activity implements OnClickListener {
// TableLayout tablelayout_Log = null;
private Button deleteButton;
private Button updateButton;
private Button cancelButton;
// Button searchButton = null;
private static EditText dateEdit;
private EditText priceEdit;
private EditText pumpEdit;
private TextView costView;
private EditText odometerEdit;
private EditText odometerPreEdit;
private TextView fconView;
private TextWatcher textWatcher;
private String priceEditStr ="0.0",pumpEditStr="0.0";
private String odmEditStr = "";
private String preOdm = "";
private String bundleDate;
private String bundlePrice;
private String bundlePump;
private String bundleCost;
private String bundleOdometer;
private String bundleFcon;
private String dateEditTextValue;
private String priceEditTextValue;
private String pumpEditTextValue;
private String costTextViewValue;
private String odometerEditTextValue;
private String fconTextViewValue;
double result;
double resultCon;
private int mYear;
private int mMonth;
private int mDay;
static final int DATE_DIALOG_ID = 0;
public boolean isNumeric(String str)
{
return str.matches("-?\\d+(\\.\\d+)?");
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.update);
costView = (TextView)findViewById(R.id.tcost);
dateEdit = (EditText)findViewById(R.id.date);
priceEdit = (EditText)findViewById(R.id.fuelprice);
pumpEdit = (EditText)findViewById(R.id.fuelpump);
odometerEdit = (EditText)findViewById(R.id.odometer);
odometerPreEdit = (EditText)findViewById(R.id.odometerPre);
fconView = (TextView)findViewById(R.id.fcon);
cancelButton = (Button) findViewById(R.id.cancelBTN);
cancelButton.setOnClickListener(this);
updateButton = (Button) findViewById(R.id.updateBTN);
updateButton.setOnClickListener(this);
deleteButton = (Button) findViewById(R.id.deleteBTN);
deleteButton.setOnClickListener(this);
Bundle takeBundledData = getIntent().getExtras();
// First we need to get the bundle data that pass from the UndergraduateListActivity
bundleDate = takeBundledData.getString("clickedDate");
bundlePrice = takeBundledData.getString("clickedPrice");
bundlePump = takeBundledData.getString("clickedPump");
bundleCost = takeBundledData.getString("clickedCost");
bundleOdometer = takeBundledData.getString("clickedOdometer");
bundleFcon = takeBundledData.getString("clickedFCon");
// Set the values that we extracted from the Bundle in the EditText fields
dateEdit.setText(bundleDate);
priceEdit.setText(bundlePrice);
pumpEdit.setText(bundlePump);
costView.setText(bundleCost);
odometerEdit.setText(bundleOdometer);
fconView.setText(bundleFcon);
dateEdit.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// showDialog(DATE_DIALOG_ID);
DialogFragment newFragment = new DatePickerFragment();
newFragment.show(getFragmentManager(), "datePicker");
}
});
priceEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
if (! android.text.TextUtils.isEmpty(priceEdit.getText())) {
priceEditStr = priceEdit.getText().toString().trim();
}
if (! android.text.TextUtils.isEmpty(pumpEdit.getText())) {
pumpEditStr = pumpEdit.getText().toString().trim();
}
result = Double.parseDouble(priceEditStr) * Double.parseDouble(pumpEditStr);
costView.setText(" "+result);
}
});
pumpEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
//here, after we introduced something in the EditText we get the string from it
if(!priceEdit.getText().toString().trim().equalsIgnoreCase(""))
priceEditStr = priceEdit.getText().toString().trim();
if(!pumpEdit.getText().toString().trim().equalsIgnoreCase(""))
pumpEditStr = pumpEdit.getText().toString().trim();
if(!priceEdit.getText().toString().trim().equalsIgnoreCase("") && !pumpEdit.getText().toString().trim().equalsIgnoreCase(""))
{
result = Double.parseDouble(priceEditStr) * Double.parseDouble(pumpEditStr);
costView.setText(" "+result);
}
}
});
odometerEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
//here, after we introduced something in the EditText we get the string from it
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase(""))
odmEditStr = odometerEdit.getText().toString().trim();
if(!odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
preOdm = odometerPreEdit.getText().toString().trim();
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase("") && !pumpEdit.getText().toString().trim().equalsIgnoreCase("") && !odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
{
resultCon = Double.parseDouble(odmEditStr) - Double.parseDouble(preOdm) / Double.parseDouble(pumpEditStr);
fconView.setText(" "+resultCon);
}
}
});
odometerPreEdit.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
//here, after we introduced something in the EditText we get the string from it
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase(""))
odmEditStr = odometerEdit.getText().toString().trim();
if(!odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
preOdm = odometerPreEdit.getText().toString().trim();
if(!odometerEdit.getText().toString().trim().equalsIgnoreCase("") && !pumpEdit.getText().toString().trim().equalsIgnoreCase("") && !odometerPreEdit.getText().toString().trim().equalsIgnoreCase(""))
{
resultCon = Double.parseDouble(odmEditStr) - Double.parseDouble(preOdm) / Double.parseDouble(pumpEditStr);
fconView.setText(" "+resultCon);
}
}
});
}
@Override
public void onClick(View v) {
// We need to update or delete details which is in the EditText fields after user edit the values
// These values are the ContentValues that we are going to use in future
dateEditTextValue = dateEdit.getText().toString();
priceEditTextValue = priceEdit.getText().toString();
pumpEditTextValue = pumpEdit.getText().toString();
costTextViewValue = costView.getText().toString();
odometerEditTextValue = odometerEdit.getText().toString();
fconTextViewValue = fconView.getText().toString();
// It is easy to set values to the POJO class and pass the class instance to the updateUgraduateDetails() method
fuelLogPojo fuelLogPojo = new fuelLogPojo();
fuelLogPojo.setdate(bundleDate);
fuelLogPojo.setprice(bundlePrice);
fuelLogPojo.setpump(bundlePump);
fuelLogPojo.setcost(bundleCost);
fuelLogPojo.setodometer(bundleOdometer);
fuelLogPojo.setfcon(bundleFcon);
if(v.getId() == R.id.cancelBTN){
finish();
}else if(v.getId() == R.id.updateBTN){
updateLog(fuelLogPojo);
}else if(v.getId() == R.id.deleteBTN){
deleteLog(fuelLogPojo);
}
}
private void deleteLog(fuelLogPojo deletefuelLogPojo) {
// TODO Auto-generated method stub
AndroidOpenDbHelper androidOpenDbHelper = new AndroidOpenDbHelper(this);
SQLiteDatabase sqliteDatabase = androidOpenDbHelper.getWritableDatabase();
String[] whereClauseArgument = new String[1];
whereClauseArgument[0] = deletefuelLogPojo.getdate();
// Only difference between UPDATE and DELETE is
//DELETE does not have ContentValues part
sqliteDatabase.delete(AndroidOpenDbHelper.TABLE_NAME_LOG, AndroidOpenDbHelper.KEY_DATE+"=?", whereClauseArgument);
sqliteDatabase.close();
finish();
}
private void updateLog(fuelLogPojo updatefuelLogPojo) {
// TODO Auto-generated method stub
AndroidOpenDbHelper androidOpenDbHelper = new AndroidOpenDbHelper(this);
SQLiteDatabase sqliteDatabase = androidOpenDbHelper.getWritableDatabase();
// ContentValues class is used to store a set of values
//It is like name-value pairs
// "value" part contains the values that we are going to UPDATE
ContentValues contentValues = new ContentValues();
contentValues.put(AndroidOpenDbHelper.KEY_DATE, dateEditTextValue);
contentValues.put(AndroidOpenDbHelper.KEY_PRICE, priceEditTextValue);
contentValues.put(AndroidOpenDbHelper.KEY_FUEL, pumpEditTextValue);
contentValues.put(AndroidOpenDbHelper.KEY_COST, costTextViewValue);
contentValues.put(AndroidOpenDbHelper.KEY_ODM, odometerEditTextValue);
contentValues.put(AndroidOpenDbHelper.KEY_CON, fconTextViewValue);
// If we are using multiple whereClauseArguments, array size should have to change
String[] whereClauseArgument = new String[1];
whereClauseArgument[0] = updatefuelLogPojo.getdate();
System.out.println("whereClauseArgument[0] is :" + whereClauseArgument[0]);
/**
* This is the normal SQL query for UPDATE
UPDATE table_name
SET column1=value, column2=value2,...
WHERE some_column=some_value
*/
sqliteDatabase.update(AndroidOpenDbHelper.TABLE_NAME_LOG, contentValues, AndroidOpenDbHelper.KEY_DATE+"=?", whereClauseArgument);
// For two whereClauseArguments
//sqliteDatabase.update(AndroidOpenDbHelper.TABLE_NAME_GPA, contentValues, BaseColumns._ID+"=? AND name=?", whereClauseArgument);
sqliteDatabase.close();
finish();
}
public static class DatePickerFragment extends DialogFragment
implements DatePickerDialog.OnDateSetListener {
public EditText editText;
DatePicker dpResult;
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Use the current date as the default date in the picker
final Calendar c = Calendar.getInstance();
int year = c.get(Calendar.YEAR);
int month = c.get(Calendar.MONTH);
int day = c.get(Calendar.DAY_OF_MONTH);
//return new DatePickerDialog(getActivity(), (EditSessionActivity)getActivity(), year, month, day);
// Create a new instance of DatePickerDialog and return it
return new DatePickerDialog(getActivity(), this, year, month, day);
}
public void onDateSet(DatePicker view, int year, int month, int day) {
dateEdit.setText(String.valueOf(day) + "/"
+ String.valueOf(month + 1) + "/" + String.valueOf(year));
// set selected date into datepicker also
}}}
答案 0 :(得分：1)
密切关注pumpEditStr中的值。如果它为零，那么你的除法运算将等于无穷大。