Kotlin provides the ability to extend a class with new functionality without having to inherit from the class or use any type of design pattern such as Decorator. This is done via special declarations called extensions.
Questions tagged [kotlin-extension]
333 questions
0
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1 answer
Fragment View is null when try to access from Activity
I have created a Fragment which is in ViewPager. Fragment is loading fine.
I am using a button to swipe fragments in viewpager and before swiping, I want to check validations. So I did this in Activity :
val pos: Int = viewPager.currentItem
…
Nir Patel
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4 answers
Kotlin Extensions - Inflate Custom Views
I'm new to kotlin, I Have an adapter class and I need to inflate a view. but recently I'm facing an error saying "Unresolved reference: R"
Like in the image below :
So, how can I inflate this view? I have imported the following:
import…
Tamim Attafi
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4 answers
can we swap two numbers in kotlin using two variables and take input from user?
I tried it by the following program but it shows the error that kotlin variable is expected:
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Varun Gandhi
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Can I extend Comparable in Kotlin?
I wanted to implement min()/max() aliases for the Kotlin's ComparablecoerceAtLeast()/coerceAtMost(), if nothing else for the exercise of extending an Interface (I've only extended classes so far).
I tried this:
fun Comparable.max(other:T) :…
Travis Griggs
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Android Studio doesn't highlight invalid Kotlin receiver when using @IdRes
I expected that using extension:
fun @receiver:IdRes Int.findView() = findViewById(this)
On resource that is not defined in R.id would highlight the call, but it doesn't:
Is this a bug?
EDIT
Linked question and answers do not answer this…
xinaiz
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2 answers
Kotlin : The specified child already has a parent. You must call removeView() on the child's parent first
Can anyone tell me what is the problem. This is the code:
package com.mohdjey.user.inflate
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.os.strictmode.WebViewMethodCalledOnWrongThreadViolation
import…
Jeylani Osman
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1 answer
Kotlin - Replace a single two-methods interface with two different one-method interfaces
First of all, I want to clarify that my questions is for a personal code-style preference.
Let's say I have a method which takes an interface as parameter, and the said interface has two methods in it.
In kotlin, implementing the interface…
Lampione
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votes
2 answers
Break out of lambda in kotlin
I am trying to add an very useful extension method to Java’s InputStream class, since we know stream parsing requires several lines of boiler plate code and In my application we need to process stream multiple times.
So far my extension function…
Manish Bansal
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Kotlin Activity changes writing order from left to right to right to left (Phone w/ different language)
I have a Kotlin project in Android Studio and I developed a simple app...
My real device is in a different language so when I run the app on my device all the activity is stuck to the right (like you write in Hebrew...)
I want to keep the order left…
Adam
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1 answer
Kotlin represent array with boolean indexing
I want to have a 2x2 2d array of int in kotlin but the indexing should be using booleans like this:
| true | false |
----------------------
true | 0 | 75 |
----------------------
false | 1 | 34 |
I know I can use a 2d array of…
Jofbr
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0 answers
when I choose am item from spinner it doesn't show, but its selected
I have an activity were I have to show a list of names in a spinner, the names are in a Firebase database and I managed to do that and it works just fine
here is how it looks like:
the items added in the spinner
but after I select an item it just…
sho
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1 answer
android studio kotlin cannot get data to display
Complete Newbie to Kotlin, trying to get three values to pass across from text boxes to another page, I am getting no errors put the info is not either being passed across or displayed I have tried for hours to get this to work with no avail.page 1…
James24
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1 answer
How can I extension Java class with Kotlin to use like static fun?
public class TestA {
public static void a() {}
}
fun TestA.b(){}
How can I extension Java class with Kotlin to use like static fun ?
just like TestA.b() to use this fun
wanbo
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Kotlin, how can retry request if get error when tap on button of dialog
Let imagine situation on Kotlin, when we try get request but hasn't internet connection and we get error, then show AlertDialog, and we need retry request if user click on "positive button".
This method check for exist user by phone number:
override…
nicolas asinovich
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1 answer
Kotlin, set value to TextView use callback interface
Such mini example, in Java I have:
public static void getPlaceName(GoogleApiClient mGoogleApiClient, String placeId, @NonNull PlaceNameCallback callback) {
Places.GeoDataApi.getPlaceById(mGoogleApiClient, placeId)
…
nicolas asinovich
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