I want to do something like this: (the code is in java)
Pair[] pairs = new Pair[1];I want to convert this code to kotlin, the problem is I don't know how to initialize this array.This is the code I have:
val prof_intent = Intent(this, NewObjectiveActivity::class.java)val pairs = arrayOf(1)pairs[0] = Pair<View, String>(fabNewObjective, "activity_trans")val options = ActivityOptions.makeSceneTransitionAnimation(this, pairs)startActivity(prof_intent, options.toBundle())Best Answer
First Solution:
You can define an array list of pairs as you had in your java code in this way:
val pairList = ArrayList<Pair<String, Int>>()Then you can define your variable and add it to your list:
val pair = Pair("hi", 12)pairList.add(pair)Second Solution:
var pairs = arrayOf(Pair("hi", 12), Pair("bye", 13))Third Solution:
pairs = arrayOf("hi" to 12, "bye" to 13)Just pass the pairs in the method indicating each pairs with their index number.
The method makeSceneTransitionAnimation(Activity activity, Pair<View, String>... sharedElements) in the ActivityOptions class requires an activity as the first parameter and could have as many pairs as possible as the following parameter.
See the code below for a better understanding:
val pair = listOf<Pair<View, String>>(Pair<View, String>(img, "image_shared"),Pair<View, String>(txtview, "text_shared"),Pair<View, String>(imgView, "image_view_shared"))val options: ActivityOptions = ActivityOptions.makeSceneTransitionAnimation(this, pair[0], pair[1], pair[2])Intent(this, SharedElementActivity::class.java).also {startActivity(it, options.toBundle())}To give an example that's then used in an activity transition:
var pairs = arrayListOf<Pair<View,String>>()for (view in listOfViewsToBeTransitioned) {val transitionPair = Pair.create(view, view.id.toString())pairs.add(transitionPair)}val pairsArray:Array<Pair<View,String>> = pairs.toTypedArray()val transitionOptions = ActivityOptions.makeSceneTransitionAnimation(this, *(pairsArray))val intent = Intent(this, targetActivity::class.java)startActivity(intent, transitionOptions.toBundle())The * splat operator expands a typed array into the varargs that makeSceneTransitionAnimation will accept. This example also assumes there is a meaningful value in view.id, I generally make this the resource identifier of the drawable used in the view.
According to Google Documents , it's better to do like this :
// Rename the Pair class from the Android framework to avoid a name clashimport android.util.Pair as UtilPair...val options = ActivityOptions.makeSceneTransitionAnimation(this,UtilPair.create(view1, "agreedName1"),UtilPair.create(view2, "agreedName2"))