Refactoring Kotlin method using a lambda
I have the following emun class to represent my navigation bar views.
enum class NavigationPosition(val position: Int, val id: Int) {
HOME(0, R.id.nav_home),
SEARCH(1, R.id.nav_search),
PROFILE(2, R.id.nav_profile),
SETTINGS(3, R.id.nav_settings);
}
I'm currently using the following method to do a reverse lookup by position
fun getByPosition(position: Int): NavigationPosition = when (position) {
0 -> NavigationPosition.HOME
1 -> NavigationPosition.SEARCH
2 -> NavigationPosition.PROFILE
3 -> NavigationPosition.SETTINGS
else -> NavigationPosition.HOME
}
var navigationPosition = getByPosition(position)
Is there a simpler way I can refactor getByPosition by using a Kotlin lambda or extension function?
lambda kotlin kotlin-extension
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
add a comment |
I have the following emun class to represent my navigation bar views.
enum class NavigationPosition(val position: Int, val id: Int) {
HOME(0, R.id.nav_home),
SEARCH(1, R.id.nav_search),
PROFILE(2, R.id.nav_profile),
SETTINGS(3, R.id.nav_settings);
}
I'm currently using the following method to do a reverse lookup by position
fun getByPosition(position: Int): NavigationPosition = when (position) {
0 -> NavigationPosition.HOME
1 -> NavigationPosition.SEARCH
2 -> NavigationPosition.PROFILE
3 -> NavigationPosition.SETTINGS
else -> NavigationPosition.HOME
}
var navigationPosition = getByPosition(position)
Is there a simpler way I can refactor getByPosition by using a Kotlin lambda or extension function?
lambda kotlin kotlin-extension
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
add a comment |
I have the following emun class to represent my navigation bar views.
enum class NavigationPosition(val position: Int, val id: Int) {
HOME(0, R.id.nav_home),
SEARCH(1, R.id.nav_search),
PROFILE(2, R.id.nav_profile),
SETTINGS(3, R.id.nav_settings);
}
I'm currently using the following method to do a reverse lookup by position
fun getByPosition(position: Int): NavigationPosition = when (position) {
0 -> NavigationPosition.HOME
1 -> NavigationPosition.SEARCH
2 -> NavigationPosition.PROFILE
3 -> NavigationPosition.SETTINGS
else -> NavigationPosition.HOME
}
var navigationPosition = getByPosition(position)
Is there a simpler way I can refactor getByPosition by using a Kotlin lambda or extension function?
lambda kotlin kotlin-extension
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
I have the following emun class to represent my navigation bar views.
enum class NavigationPosition(val position: Int, val id: Int) {
HOME(0, R.id.nav_home),
SEARCH(1, R.id.nav_search),
PROFILE(2, R.id.nav_profile),
SETTINGS(3, R.id.nav_settings);
}
I'm currently using the following method to do a reverse lookup by position
fun getByPosition(position: Int): NavigationPosition = when (position) {
0 -> NavigationPosition.HOME
1 -> NavigationPosition.SEARCH
2 -> NavigationPosition.PROFILE
3 -> NavigationPosition.SETTINGS
else -> NavigationPosition.HOME
}
var navigationPosition = getByPosition(position)
Is there a simpler way I can refactor getByPosition by using a Kotlin lambda or extension function?
lambda kotlin kotlin-extension
lambda kotlin kotlin-extension
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
asked Nov 23 '18 at 18:23
patrickandroidpatrickandroid
1,47022241
1,47022241
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
As already mentioned, you can use NavigationPosition.values(). However, the current ways proposed are NOT memory efficient. The values function creates a new array every time it is called. I highly recommend you cache it in a static variable to make sure it's not initialized every time you call it, as this isn't efficient.
Combining a comparative approach with a cached approach, you can use a companion object inside the enum. Now, like I said, caching the values is the best option here, so in addition to a method (as mentioned in both the other answers), you also create a field containing the values, to avoid re-calling it every time you call the method.
companion object {
private val values = values()
fun getPositionById(id: Int) = if(id < values.size && id >= 0) values[i] else HOME
}
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
add a comment |
I think you want this:
NavigationPosition.values()[position]
NavigationPosition.values() is an array containing the enum values.
So you can get the same result by:
fun getByPosition(position: Int): NavigationPosition {
return if (position >= NavigationPosition.values().size)
NavigationPosition.HOME
else
NavigationPosition.values()[position]
}
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
As already mentioned, you can use NavigationPosition.values(). However, the current ways proposed are NOT memory efficient. The values function creates a new array every time it is called. I highly recommend you cache it in a static variable to make sure it's not initialized every time you call it, as this isn't efficient.
Combining a comparative approach with a cached approach, you can use a companion object inside the enum. Now, like I said, caching the values is the best option here, so in addition to a method (as mentioned in both the other answers), you also create a field containing the values, to avoid re-calling it every time you call the method.
companion object {
private val values = values()
fun getPositionById(id: Int) = if(id < values.size && id >= 0) values[i] else HOME
}
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
add a comment |
As already mentioned, you can use NavigationPosition.values(). However, the current ways proposed are NOT memory efficient. The values function creates a new array every time it is called. I highly recommend you cache it in a static variable to make sure it's not initialized every time you call it, as this isn't efficient.
Combining a comparative approach with a cached approach, you can use a companion object inside the enum. Now, like I said, caching the values is the best option here, so in addition to a method (as mentioned in both the other answers), you also create a field containing the values, to avoid re-calling it every time you call the method.
companion object {
private val values = values()
fun getPositionById(id: Int) = if(id < values.size && id >= 0) values[i] else HOME
}
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
add a comment |
As already mentioned, you can use NavigationPosition.values(). However, the current ways proposed are NOT memory efficient. The values function creates a new array every time it is called. I highly recommend you cache it in a static variable to make sure it's not initialized every time you call it, as this isn't efficient.
Combining a comparative approach with a cached approach, you can use a companion object inside the enum. Now, like I said, caching the values is the best option here, so in addition to a method (as mentioned in both the other answers), you also create a field containing the values, to avoid re-calling it every time you call the method.
companion object {
private val values = values()
fun getPositionById(id: Int) = if(id < values.size && id >= 0) values[i] else HOME
}
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
As already mentioned, you can use NavigationPosition.values(). However, the current ways proposed are NOT memory efficient. The values function creates a new array every time it is called. I highly recommend you cache it in a static variable to make sure it's not initialized every time you call it, as this isn't efficient.
Combining a comparative approach with a cached approach, you can use a companion object inside the enum. Now, like I said, caching the values is the best option here, so in addition to a method (as mentioned in both the other answers), you also create a field containing the values, to avoid re-calling it every time you call the method.
companion object {
private val values = values()
fun getPositionById(id: Int) = if(id < values.size && id >= 0) values[i] else HOME
}
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
answered Nov 23 '18 at 21:01
ZoeZoe
11.9k74480
11.9k74480
add a comment |
add a comment |
I think you want this:
NavigationPosition.values()[position]
NavigationPosition.values() is an array containing the enum values.
So you can get the same result by:
fun getByPosition(position: Int): NavigationPosition {
return if (position >= NavigationPosition.values().size)
NavigationPosition.HOME
else
NavigationPosition.values()[position]
}
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
add a comment |
I think you want this:
NavigationPosition.values()[position]
NavigationPosition.values() is an array containing the enum values.
So you can get the same result by:
fun getByPosition(position: Int): NavigationPosition {
return if (position >= NavigationPosition.values().size)
NavigationPosition.HOME
else
NavigationPosition.values()[position]
}
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
add a comment |
I think you want this:
NavigationPosition.values()[position]
NavigationPosition.values() is an array containing the enum values.
So you can get the same result by:
fun getByPosition(position: Int): NavigationPosition {
return if (position >= NavigationPosition.values().size)
NavigationPosition.HOME
else
NavigationPosition.values()[position]
}
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
I think you want this:
NavigationPosition.values()[position]
NavigationPosition.values() is an array containing the enum values.
So you can get the same result by:
fun getByPosition(position: Int): NavigationPosition {
return if (position >= NavigationPosition.values().size)
NavigationPosition.HOME
else
NavigationPosition.values()[position]
}
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
edited Nov 23 '18 at 19:02
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
answered Nov 23 '18 at 18:41
forpasforpas
13.6k3624
13.6k3624
add a comment |
add a comment |
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