How to convert Calendar to Date in Kotlin?

android date kotlin calendar

14,884

Solution 1

Thank you Sergey... The code runs ok. But I have been disappointed because I added a useless line of code in order to debug and I had put a breakpoint on it :

val datePlusOneMonth: Date = cal.time
val ok = false

And I had put the breakpoint on the "val ok = false" and the debugger never stopped on "val ok = false" because "ok" was never used.

Then to have the debugger stop on "val ok = false" I had to do the following :

val datePlusOneMonth: Date = cal.time
val ok = false
val ok2 = ok

And then I could add the breakpoing on "val ok = false" and yes the code runs well.

Solution 2

try this code

val datePlusOneMonth = Calendar.getInstance().run {
    add(Calendar.MONTH, 1)
    time
}

14,884

KotlinIsland

I have been involved in many projects for many companies such as Renault, Orange, SFR, Poclain Hydraulics, Bouygues Telecom... I have been involved in a Car-to-Car European Research Project called GST (Global Systems For Telematics).

Updated on May 25, 2022

Comments

KotlinIsland almost 2 years
I am trying to add one month to a date with Calendar.getInstance() but I can't figure out why there is error "java.lang.ClassCastException : java.util.Date cannot be cast to java.lang.Number" when trying to get the Calendar to a Date object.

Here's the source code that I am using :
```
    val date = Date()
    val cal = Calendar.getInstance()
    cal.time = date
    cal.add(Calendar.MONTH, 1)
    val datePlusOneMonth: Date = cal.time
```
- Sergio about 5 years
  
  The code you provided works fine on my side. Maybe error appears somewhere else in your code? Please check logs and look for the line number of the error
- Amine about 5 years
  
  cal.time = date has not need here, otherwise what line gives you this error ?
- KotlinIsland about 5 years
  
  The error happens on val datePlusOneMonth: Date = cal.time
- KotlinIsland about 5 years
  
  Sergey, are you sure that it runs ok ? Because the exception does not trigger any bug in the application. It is only when I put a breakpoint and then go to Evaluate Expression window that I see the error when calling cal.time
- KotlinIsland about 5 years
  
  Amine, you say right, cal.time = Date is not needed. Thanks. (Error still happening anyway)
- Sergio about 5 years
  
  Yes, the code runs fine on my side
- KotlinIsland about 5 years
  
  So you have a value in datePlusOneMonth ?
- KotlinIsland about 5 years
  
  imgur.com/a/v9cgM2O
- Sergio about 5 years
  
  Yes I have. You can set log after line val datePlusOneMonth: Date = cal.time and check it
- KotlinIsland about 5 years
  
  One thing I find bizarre is that when adding a try/catch block, then the code does not go in the catch block...
- Sergio about 5 years
  
  Because it is not throwing the exception)
KotlinIsland about 5 years

Ok thanks for the answer, but we figured out that my code runs correctly. Anyway I'll consider this next time.