Fixes messages FAB's position when open

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/layouts/DisappearingFloatingButton.kt

@@ -20,16 +20,19 @@
  */
 package com.vitorpamplona.amethyst.ui.layouts
 
+import androidx.compose.foundation.border
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.BoxScope
-import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.padding
 import androidx.compose.material3.BottomAppBarScrollBehavior
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.graphicsLayer
 import androidx.compose.ui.layout.layout
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.unit.dp
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -42,10 +45,17 @@ fun DisappearingFloatingButton(
     // 1.0 = fully visible, 0.0 = fully hidden
     val progress = (1f - scrollBehavior.state.collapsedFraction).coerceAtLeast(0.001f)
 
+    val border =
+        with(LocalDensity.current) {
+            20.dp.toPx()
+        }
+
     Box(
         modifier =
             Modifier
-                .size(75.dp)
+                .border(1.dp, Color.Green)
+                .padding(20.dp)
+                .border(1.dp, Color.Red)
                 .layout { measurable, constraints ->
                     val placeable = measurable.measure(constraints)
                     // Adjust the height of the layout so the FAB doesn't leave a "hole"
@@ -54,7 +64,7 @@ fun DisappearingFloatingButton(
                         placeable.placeRelative(0, 0)
                     }
                 }.graphicsLayer {
-                    this.translationY = this.size.height / 3.5f
+                    this.translationY = border
                     this.scaleX = progress
                     this.scaleY = progress
                     this.alpha = progress