Kotlin - Class secondary constructor with different parameter

Question

Whilst converting a rather simple application from Java to Kotlin I came across one 'problem' I can't seem to fix.

I have a class ScanInfo that looks like this in Java (without getters and setters)

public class ScanInfo {
    private String source;
    private String label_type;
    private String data;

    public ScanInfo(Intent intent) {
        ... Get Info from intent and assign the values ...
        this.source = ...
        this.label_type = ....
        this.data = ....
    }
}

Now in Kotlin i can create the class

class ScanInfo (var source: String, var label_type: String, var data: String)

But I have no idea how to get it to work so I can create a ScanInfo object with Intent as parameter. I tried with companion, object, companion object but I can't seem to find the right syntax.

Am I wrong to look for such a solution while using Kotlin or am I just not using the right kotlin-constructor? If it's possible, how can I create a ScanInfo object with an Intent as parameter?

var result = ScanInfo(intent)

Thanks in advance.

Alex Romanov · Accepted Answer · 2017-08-07 09:57:53Z

2

That's the way:

class ScanInfo(intent: Intent) {
    private val source = intent.source
    private val labelType = intent.labelType
    private val data = intent.data
}

OR

class ScanInfo(intent: Intent) {
    private val source: String
    private val labelType: String
    private val data: String

    init {
        source = intent.data
        labelType = intent.data
        data = intent.data
    }
}

edited Aug 7, 2017 at 9:57

answered Aug 7, 2017 at 9:53

Alex Romanov

12k6 gold badges52 silver badges53 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Oussema Aroua Over a year ago

you need to add getters/setters too or change the visibility

Alex Romanov Over a year ago

Not sure if OP needs getters/setters for his class, but yes, you're right.

Oussema Aroua Over a year ago

using the init method is the best choice

Thomas VC Over a year ago

I've use the second option because I had more actions to be completed before getting the source/label_type/data information. By removing the private indication of the declaration and changing them to var's, I have my needed solution. Thank you!

Collectives™ on Stack Overflow

Kotlin - Class secondary constructor with different parameter

1 Answer 1

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related