AnimatableSpacer.kt added.

Author: commandiron

animatable-compose/src/main/java/com/commandiron/animatable_compose/AnimatableSpacer.kt

@@ -1,2 +1,78 @@
 package com.commandiron.animatable_compose
 
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.width
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.DpSize
+import com.commandiron.animatable_compose.state.AnimatableState
+import com.commandiron.animatable_compose.state.AnimatableStateTag
+import com.commandiron.animatable_compose.state.SharedAnimatableState
+
+@Composable
+fun AnimatableSpacer(
+    modifier: Modifier = Modifier,
+    state: SharedAnimatableState,
+    stateIndex: Int = 0,
+    fixedWidth: Dp = Dp.Unspecified,
+    fixedHeight: Dp = Dp.Unspecified,
+) {
+    val stateIn = state.getState(AnimatableStateTag.SPACER, stateIndex) ?: throw (
+        IllegalArgumentException("no animatableState has this index: $stateIndex")
+    )
+    Spacer(
+        modifier = Modifier
+            .width(
+                when (fixedWidth) {
+                    Dp.Unspecified -> if (stateIn.animatedSize == DpSize.Unspecified) {
+                        Dp.Unspecified
+                    } else stateIn.animatedSize.width
+                    Dp.Infinity -> stateIn.screenWidth
+                    else -> fixedWidth
+                }
+            )
+            .height(
+                when (fixedHeight) {
+                    Dp.Unspecified -> if (stateIn.animatedSize == DpSize.Unspecified) {
+                        Dp.Unspecified
+                    } else stateIn.animatedSize.height
+                    Dp.Infinity -> stateIn.screenHeight
+                    else -> fixedHeight
+                }
+            )
+            .then(modifier)
+    )
+}
+
+@Composable
+fun AnimatableSpacer(
+    modifier: Modifier = Modifier,
+    state: AnimatableState,
+    fixedWidth: Dp = Dp.Unspecified,
+    fixedHeight: Dp = Dp.Unspecified,
+) {
+    Spacer(
+        modifier = Modifier
+            .width(
+                when (fixedWidth) {
+                    Dp.Unspecified -> if (state.animatedSize == DpSize.Unspecified) {
+                        Dp.Unspecified
+                    } else state.animatedSize.width
+                    Dp.Infinity -> state.screenWidth
+                    else -> fixedWidth
+                }
+            )
+            .height(
+                when (fixedHeight) {
+                    Dp.Unspecified -> if (state.animatedSize == DpSize.Unspecified) {
+                        Dp.Unspecified
+                    } else state.animatedSize.height
+                    Dp.Infinity -> state.screenHeight
+                    else -> fixedHeight
+                }
+            )
+            .then(modifier)
+    )
+}

animatable-compose/src/main/java/com/commandiron/animatable_compose/state/AnimatableState.kt

@@ -907,7 +907,7 @@ enum class AnimationState {
 }
 
 enum class AnimatableStateTag {
-    BOX, TEXT, CARD, ICON, LAZY_ROW
+    BOX, TEXT, CARD, ICON, LAZY_ROW, SPACER
 }
 
 @Composable
@@ -1178,4 +1178,26 @@ fun rememberAnimatableLazyRowState(
             onAnimation = onAnimation
         )
     }
+}
+
+@Composable
+fun rememberAnimatableSpacerState(
+    index: Int = 0,
+    initialSize: DpSize? = null,
+    targetSize: DpSize? = null,
+    toTargetSizeAnimationSpec: AnimationSpec<Size>? = null,
+    toInitialSizeAnimationSpec: AnimationSpec<Size>? = null,
+    onSizeAnimation: (AnimationState) -> Unit = {},
+): AnimatableState {
+    return remember {
+        AnimatableState(
+            animatableStateTag = AnimatableStateTag.SPACER,
+            index = index,
+            initialSize = initialSize,
+            targetSize = targetSize,
+            toTargetSizeAnimationSpec = toTargetSizeAnimationSpec,
+            toInitialSizeAnimationSpec = toInitialSizeAnimationSpec,
+            onSizeAnimation = onSizeAnimation
+        )
+    }
 }

app/src/main/java/com/commandiron/animatablecompose/Show8InfoCard.kt

@@ -15,10 +15,7 @@ import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.*
 import coil.compose.AsyncImage
-import com.commandiron.animatable_compose.AnimatableBox
-import com.commandiron.animatable_compose.AnimatableCard
-import com.commandiron.animatable_compose.AnimatableLazyRow
-import com.commandiron.animatable_compose.AnimatableText
+import com.commandiron.animatable_compose.*
 import com.commandiron.animatable_compose.state.*
 import dev.chrisbanes.snapper.ExperimentalSnapperApi
 import dev.chrisbanes.snapper.SnapOffsets
@@ -63,13 +60,18 @@ fun Show8InfoCard() {
         initialOffset = DpOffset(x = 0.dp, y = 300.dp),
         targetOffset = DpOffset(x = 0.dp, y = 0.dp)
     )
+    val animatableSpacerState = rememberAnimatableSpacerState(
+        initialSize = DpSize(width = 0.dp, height = 0.dp),
+        targetSize = DpSize(width = 0.dp, height = 16.dp),
+    )
 
 
     val infoCards by remember { mutableStateOf(InfoCard.infoCards) }
 
     val cardStates = mutableListOf<AnimatableState>()
     val boxStates = mutableListOf<AnimatableState>()
     val textStates = mutableListOf<AnimatableState>()
+    val spacerStates = mutableListOf<AnimatableState>()
 
     infoCards.indices.forEach { index ->
         cardStates.add(
@@ -103,6 +105,13 @@ fun Show8InfoCard() {
                 toTargetAnimationSpec = tween(250)
             )
         )
+        spacerStates.add(
+            animatableSpacerState.copy(
+                index = index,
+                toTargetAnimationSpec = tween(250),
+                toInitialAnimationSpec = tween(250)
+            )
+        )
 
     }
 
@@ -111,6 +120,7 @@ fun Show8InfoCard() {
                 + cardStates
                 + boxStates
                 + textStates
+                + spacerStates
     )
 
     Box(
@@ -155,6 +165,10 @@ fun Show8InfoCard() {
                                         fontSize = 22.sp,
                                         fontWeight = FontWeight.Bold
                                     )
+                                    AnimatableSpacer(
+                                        stateIndex = index,
+                                        state = sharedAnimatableState
+                                    )
                                     AnimatableText(
                                         text = infoCards[index].info,
                                         stateIndex = index,