0
我正在研究基於SQLite的應用程序。一切工作正常,除了我的方法中的if-else語句。儲蓄和東西的工作,只是檢查給我一個相當高的血壓。我希望你是一個比我更聰明,發現了可能是明顯的錯誤我犯了:如果+嘗試 - 趕上方法不正常
public void save() {
// get length of EditText
int dateLength, mileageLength, amountLength, lpriceLength, tpriceLength;
dateLength = date_widget.getText().length();
mileageLength = mileage_widget.getText().length();
amountLength = amount_widget.getText().length();
lpriceLength = price_widget.getText().length();
tpriceLength = totalPrice_widget.getText().length();
// Start save method if EditTexts are not empty.
if (dateLength > 0 || mileageLength > 0 || amountLength > 0
|| lpriceLength > 0 || tpriceLength > 0) {
// Get the value of each EditText and write it into the
// String/doubles
String date = date_widget.getText().toString();
double mileage = Double
.valueOf(mileage_widget.getText().toString());
double amount = Double.valueOf(amount_widget.getText().toString());
double lprice = Double.valueOf(price_widget.getText().toString());
double tprice = Double.valueOf(totalPrice_widget.getText()
.toString());
// Check if mileage is increasing, else cancel and show toast
int checkMileage = Integer.parseInt(db
.getSearchResult("mileage", 0));
if (checkMileage < mileage) {
try {
// if (id == null) {
db.insert(date, mileage, amount, lprice, tprice);
Toast.makeText(this, R.string.action_input_saved,
Toast.LENGTH_SHORT).show();
finish();
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(this, "ERROR " + e, Toast.LENGTH_LONG)
.show();
}
} else {
Toast.makeText(
this,
"Your current mileage must be more than the last saved mileage",
Toast.LENGTH_LONG).show();
}
} else {
Toast.makeText(this, "finish your input", Toast.LENGTH_LONG).show();
}
}
我在將對DBAdapter類的方法:
public String getSearchResult(String sql, int cmd) {
if (cmd == 0) {
String countQuery = "SELECT " + sql + " FROM " + TABLE_NAME
+ " WHERE _id = (SELECT max(_id) FROM " + TABLE_NAME + ")";
Cursor cursor = db.rawQuery(countQuery, null);
cursor.moveToFirst();
String tmp = cursor.getString(0);
cursor.close();
// return count
return tmp;
} else if (cmd == 1) {
int sum = 0;
String countQuery = "SELECT " + sql + " FROM " + TABLE_NAME;
String idQuery = "SELECT _id FROM " + TABLE_NAME
+ " WHERE _id = (SELECT max(_id) FROM " + TABLE_NAME + ")";
Cursor cursor = db.rawQuery(countQuery, null);
Cursor id = db.rawQuery(idQuery, null);
// berechnung
cursor.moveToFirst();
id.moveToFirst();
int maxId = Integer.parseInt(id.getString(0));
for (int i = 0; i < maxId; i++) {
int tmp = Integer.parseInt(cursor.getString(0));
sum = sum + tmp;
cursor.moveToNext();
}
cursor.close();
id.close();
return String.valueOf(sum);
} else if (cmd == 2 && sql == "mileage") {
int sum = 0;
String countQuery = "SELECT " + sql + " FROM " + TABLE_NAME;
String idQuery = "SELECT _id FROM " + TABLE_NAME
+ " WHERE _id = (SELECT max(_id) FROM " + TABLE_NAME + ")";
Cursor cursor = db.rawQuery(countQuery, null);
Cursor id = db.rawQuery(idQuery, null);
// berechnung
cursor.moveToFirst();
id.moveToFirst();
int maxId = Integer.parseInt(id.getString(0));
if (maxId > 1) {
int array[] = new int[maxId];
// Array füllen
for (int i = 0; i < maxId; i++) {
array[i] = Integer.parseInt(cursor.getString(0));
// sum = sum + tmp;
cursor.moveToNext();
}
for (int k = 1; k < maxId; k++) {
int tmp;
tmp = array[k] - array[k - 1];
sum = sum + tmp;
}
cursor.close();
id.close();
return String.valueOf(sum);
} else {
return "--";
}
}
return "Wrong CMD";
}
我是相當混亂,我知道
In What's not they not working?例外,或根本不檢查? – christopher 2013-04-07 12:24:06
如果我嘗試保存沒有輸入的應用程序崩潰。 – 2013-04-07 12:25:53
需要更多信息。現在我可以肯定地說你應該在你的第一個if語句中使用'&&而不是'||'。 – 2013-04-07 12:26:07