Expecting member declaration in Kotlin

I want to assign my class variable in constructor, but I get an error 'expecting member declaration'
```kotlin
class YLAService {

var context:Context?=null

class YLAService constructor(context: Context) {
this.context=context;// do something
}
}
```

In Kotlin you can use constructors like so:

class YLAService constructor(val context: Context) {

}

Even shorter:

class YLAService(val context: Context) {

}

If you want to do some processing first:

class YLAService(context: Context) {

val locationService: LocationManager

init {
locationService = context.getService(LocationManager::class.java)
}
}

If you really want to use a secondary constructor:

class YLAService {

val context: Context

constructor(context: Context) {
this.context = context
}

}

This looks more like the Java variant, but is more verbose.



See the [Kotlin reference on constructors][1].


[1]:

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I'll just add some info and give real example. When you want to initialize class && trigger some event, like some method, in **Python** we can simply call `self.some_func()` being in `__init__` or even outside. In **Kotlin** we're restricted from calling simple in the context of the class, i.e.:

```bash
class SomeClass {
this.cannotCallFunctionFromHere()
}

```

For such purposes I use `init`. It's different from constructor in a way that we don't clutter class schema && allows to make some processing.

Example where we call `this.traverseNodes ` before any further actions are done with the methods, i.e. it's done during class initialization:

```bash

class BSTIterator(root: TreeNode?) {
private var nodes = mutableListOf<Int>()
private var idx: Int = 0

init {
this.traverseNodes(root)
}


fun next(): Int {
val return_node = this.nodes[this.idx]
this.idx += 1
return return_node
}

fun hasNext(): Boolean {
when {
this.idx < this.nodes.size -> {
return true
} else -> {
return false
}
}
}

fun traverseNodes(node: TreeNode?) {
if(node!!.left != null) {
this.traverseNodes(node.left)
}
this.nodes.add(node.`val`)
if(node!!.right != null) {
this.traverseNodes(node.right)
}
}

}

```

Hope it also helps someone