From 2cbbfca73fdffba98d4acc771592f4f23d02b5c2 Mon Sep 17 00:00:00 2001
From: Adam Brown <adampsbrown@gmail.com>
Date: Wed, 23 Mar 2022 16:27:42 +0000
Subject: [PATCH] adding helper for recalculating percentage heights within a
 constraint layout - this allows percentages to be used which make of the
 screen viewport rather than the accumulated scroll height

---
 .../app/core/extensions/ConstraintLayout.kt     | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/vector/src/main/java/im/vector/app/core/extensions/ConstraintLayout.kt b/vector/src/main/java/im/vector/app/core/extensions/ConstraintLayout.kt
index b1b30da156..46d173b848 100644
--- a/vector/src/main/java/im/vector/app/core/extensions/ConstraintLayout.kt
+++ b/vector/src/main/java/im/vector/app/core/extensions/ConstraintLayout.kt
@@ -16,8 +16,12 @@
 
 package im.vector.app.core.extensions
 
+import android.view.View
 import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.constraintlayout.widget.ConstraintSet
+import androidx.core.view.children
+import androidx.core.view.doOnLayout
+import kotlin.math.roundToInt
 
 fun ConstraintLayout.updateConstraintSet(block: (ConstraintSet) -> Unit) {
     ConstraintSet().let {
@@ -26,3 +30,16 @@ fun ConstraintLayout.updateConstraintSet(block: (ConstraintSet) -> Unit) {
         it.applyTo(this)
     }
 }
+
+fun ConstraintLayout.realignPercentagesToParent() {
+    doOnLayout {
+        val rootHeight = (parent as View).height
+        children.forEach { child ->
+            val params = child.layoutParams as ConstraintLayout.LayoutParams
+            if (params.matchConstraintPercentHeight != 1.0f) {
+                params.height = (rootHeight * params.matchConstraintPercentHeight).roundToInt()
+                child.layoutParams = params
+            }
+        }
+    }
+}