I have the following problem:
I have a arraylist called "list" which contains objects of the class "SampleClass", the objects have a property "name". Now I would like to remove a object with a certain "name" value, without knowing the index.
I have tried the following:
list.remove(SampleClass("Village"))
So, the idea would be that the instance of SampleClass where the property name contains "Village" is removed from the list.
It compiles allright, but its not working.
If you want to remove all elements with that name, you can use removeAll:
list.removeAll { it.name == "Village" }
If you only want to remove the first item with that name:
If the name is the only property of the class, you should just make it a data class so equals() is based on the name. Then you could use the code you posted.
If it is not the only property, you will have to get the index in the list and remove it that way:
list.removeAt(list.indexOfFirst { it.name == "Village" })
The way you have it now, you would have to override the equals method in SampleClass to check if the name property is the same. Right now, it probably doesn't work because the default equals method won't compare the name property and so the SampleClass instance you want to remove with that property as "village" will be considered not equal to the SampleClass instance you're passing in.
Otherwise, you can also use list.filter { it.name != "village" }
equals() implementation is to make your class a data class (as suggested by Michael Kreutz). The compiler autogenerates equals() for data classes (along with hashCode(), toString(), copy(), and componentN() methods) based on the properties in the constructor.
SampleClassinto adata class?