I have an TextField with datatype Integer, so I am trying to getFieldValue() and write it to Integer field. So in runtime I have an error here:
TextField<Integer> priceField = new TextField<Integer>();
Integer newPriceFieldValue = priceField.getValue(); //here is an error in runtime
So I cant understand whats the problem - proceField.getValue() should be Integer, why string? Maybe I should another type of Field?
java.lang.ClassCastException: java.lang.String cannot be cast to
java.lang.Integer
at
ru.braginini.client.ProductForm$2.componentSelected(ProductForm.java:64)
at
ru.braginini.client.ProductForm$2.componentSelected(ProductForm.java:1)
If you are expecting only numbers to be used in this field NumberField may be the better choice.
NumberField field = new NumberField();
field.setPropertyEditorType(Integer.class);
It will ensure only numbers are entered, and save you some casting & error handling on the getValue() call.
getValue returns a String!
You want to assign this String to an Integer which causes an CastException (like it would in any Type oriented Programming language.
Try
Integer newPriceFieldValue = Integer.parseInt(priceField.getValue());
Regards,
Stefan
Related
I am reading data from Firestore. I was getting an error that said type 'Timestamp' is not a subtype of type 'String' in type cast, so I changed the createDate line below to use .toString() instead of doing as String. This solved the problem, but why did this work?
Notification.fromJson(Map<dynamic, dynamic>? json): //Transform JSON into Notification
createDate = (json?['createDate']).toString(), //This works
modifiedDate = json?['modifiedDate'] as String; //This gives the error: 'type 'Timestamp' is not a subtype of type 'String' in type cast'
The format of both of these fields is October 5, 2022 at 10:49 PM UTC-5.
Like it is said in error message, you are getting this error, because the value's type, which is coming from json is Timestamp, not String. It is better to make createDate and modifiedDate fields in Timestamp type instead of String, because it provides it's own methods, that make your work easier. Converting to String (and probably, you are parsing this String in somewhere) is redundant.
In Flutter every object class have toString() method, which is return a value with String type
(json?['createDate']).toString();
So if you write that code above, it will return a value with String type and then assign that value to createDate variable. It means you not assign json?['createDate'].
modifiedDate = json?['modifiedDate'] as String;
That line above will error because you assign that json to modifiedDate which is have different type. Cast (as) only work if the object/variable have same hierarchy, like
Child child = Child();
Parent parent = child as Parent();
json?['createDate'] is a Timestamp type object that just contains numbers describing a point in time. As you can see from the API documentation, it has a method called toString that knows how to convert that to formatted date string. Since a Timestamp it is not a subclass of String, Dart does not allow it to be cast to one. Perhaps you want to cast it to Timestamp instead, since that's what it is?
i am new in dart and just want to know how to take integer input from user in dart with null safety. i found out a way to take number input from dart which is:
String? chossenNumber = stdin. readLineSync();
if(chossenNumber !=null)
{
int number = int.parse(chossenNumber);
}
but i am unable to use number variable outside of the scope. Please tell me a way to solve this issue.
You can define the variable at the top of the class and initialize it here so you will be able to use it everywhere in the class
The solution of it very simple just take input of number as String i.e
String? chossenNumber = stdin. readLineSync();
and when you want to use this variable parse it to the 'int' i.e
if(int.parse(chossenNumber) <100)
{
print("Your Statement");
}
I have a problem with converting a string variable to TObject.
I have a query that returns two columns to me. In the first column I have varchar values that I translate into strings, and in the second column I have int values.
I want to fill a ComboBox in this way with these values:
cbx1-> AddItem (DataSet1->DataSet->Fields->Field[0]->AsString, (TObject *) (int) DataSet1->DataSet->Fields->Field[1];
As I refer to the second value which is int type, I receive some bushes, e.g., xD, etc.
By trying to convert this value to string, eg:
String temp = IntToStr (DataSet1->DataSet->Fields->Field[1]);
cbx1-> AddItem (DataSet1->DataSet->Fields->Field[0]->AsString, (TObject *) temp;
I receive an error message:
cannot cast from 'AnsiString' to 'TObject'
I do not know what further I can do to convert this value.
You cannot cast an AnsiString value to a TObject* pointer. You can only cast an integer value, or a pointer value, to a TObject* pointer. AnsiString is neither of those.
You are not retrieving the int value from the 2nd field correctly anyway. Field[1] is a pointer to an actual TField object in the Fields collection. That pointer is what you are trying to store in your ComboBox, NOT the int value that the TField represents.
You need to call Fields[1]->AsInteger to get the int value of the 2nd field, similar to how you use Fields[0]->AsString to get the string value of the 1st field:
cbx1->AddItem(
DataSet1->DataSet->Fields->Field[0]->AsString,
(TObject*) DataSet1->DataSet->Fields->Field[1]->AsInteger
// in C++, using reinterpret_cast is preferred over C-style casting:
// reinterpret_cast<TObject*>(DataSet1->DataSet->Fields->Field[1]->AsInteger)
);
This is no different than the code in your previous question:
cbx1->AddItem("one",(TObject*)1);
You are now just placing the literals "one" and 1 with runtime variables of equivalent types.
I have a jrxml file which has a field of BigDecimal value and when I try to execute the report. I get an error called " Cannot cast from BigDecimal to String in jasper". Im doing the report using ireport 5.6.0, and I get a weird error like this,
1. Cannot cast from BigDecimal to String
value = (java.lang.String)(((java.math.BigDecimal)variable_variable1.getValue())); //$JR_EXPR_ID=18$
<----------------------------------------------------------------------->
2. Cannot cast from BigDecimal to String
value = (java.lang.String)(((java.math.BigDecimal)variable_variable1.getOldValue())); //$JR_EXPR_ID=18$
<-------------------------------------------------------------------------->
3. Cannot cast from BigDecimal to String
value = (java.lang.String)(((java.math.BigDecimal)variable_variable1.getEstimatedValue())); //$JR_EXPR_ID=18$
<-------------------------------------------------------------------------------->
3 errors
I tried to change the expression class. but nothing seems to work. I need the value to get the sum and also as a field.
You have a field e.g $F{ID} with field class=java.math.BigDecimal.As you want to use this field as a string as well as decimal;
You can create two variables variable1 with variable Class=java.math.BigDecimal with Variable Expression as $F{ID}
and create another variable variable2 with variable Class=java.lang.String with Variable Expression as $F{ID}.toPlainString()
When I removed tag "printWhenExpression" for that text field with error, the error did not show again.
I'm using MySQL for dev environment but my app could be on SQLServer on staging environment.
In my database, booleans (boolean) are record as VARCHAR, integers (int) are record as VARCHAR too.
Are the methods record.getAttributeAsTYPE like getAttributeAsBoolean(java.lang.String) appropriate / sure to use ? Or is it better to use something like type myvar = new TYPE(record.getAttribute("COLUNM_NAME")) ?
What is better to use between solution 1 and 2 ?
Example 1 :
boolean mybool = record.getAttributeAsBoolean("COLUNM_NAME"); // Solution 1
boolean mybool = new Boolean(record.getAttribute("COLUNM_NAME")); // Solution 2
Example 2 :
int myint = record.getAttributeAsInt("COLUNM_NAME"); // Solution 1
int myint = new Interger(record.getAttribute("COLUNM_NAME")); // Solution 2
For me, VARCHAR may be closer to java.lang.String than java.lang.Boolean or java.lang.Integer. So I think "Solution 2", in these examples, are more sure.
It depends. If you are absolutely certain that the value of the attribute is of the type you require, you should use getAttributeAsTYPE(). How is your data source (if you're using ds.xml) defining that field? It just might be converted implicitly by smartGWT.
Looks like your value is stored as String (ex: record.setAttribute("COLUMN_NAME", "12345"), calling record.getAttributeAsInt("COLUMN_NAME") will likely fail with the type exception. In that case, the only thing you can do is instantiate Integer or convert it statically: Integer.parseInt(recrod.getAttribute()).
getAttributeAsTYPE is convenient and I use it as much as I can but you have to be sure that the value is of the right type when being set.