Migrate ContentPainterModifier to implement Modifier.Node. (#2117)

coil-kt · Feb 11, 2024 · 9832a9e · 9832a9e
1 parent 5e12570
commit 9832a9e
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Showing 3 changed files with 68 additions and 24 deletions.
diff --git a/coil-compose-base/src/main/java/coil/compose/AsyncImage.kt b/coil-compose-base/src/main/java/coil/compose/AsyncImage.kt
@@ -262,7 +262,7 @@ private fun Content(
         .contentDescription(contentDescription)
         .run { if (clipToBounds) clipToBounds() else this }
         .then(
-            ContentPainterModifier(
+            ContentPainterElement(
                 painter = painter,
                 alignment = alignment,
                 contentScale = contentScale,

diff --git a/coil-compose-base/src/main/java/coil/compose/ContentPainterModifier.kt b/coil-compose-base/src/main/java/coil/compose/ContentPainterModifier.kt
@@ -1,7 +1,7 @@
 package coil.compose
 
 import androidx.compose.ui.Alignment
-import androidx.compose.ui.draw.DrawModifier
+import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.paint
 import androidx.compose.ui.geometry.Size
 import androidx.compose.ui.geometry.isSpecified
@@ -13,41 +13,83 @@ import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.layout.IntrinsicMeasurable
 import androidx.compose.ui.layout.IntrinsicMeasureScope
-import androidx.compose.ui.layout.LayoutModifier
 import androidx.compose.ui.layout.Measurable
 import androidx.compose.ui.layout.MeasureResult
 import androidx.compose.ui.layout.MeasureScope
 import androidx.compose.ui.layout.times
-import androidx.compose.ui.platform.InspectorValueInfo
-import androidx.compose.ui.platform.debugInspectorInfo
+import androidx.compose.ui.node.DrawModifierNode
+import androidx.compose.ui.node.LayoutModifierNode
+import androidx.compose.ui.node.ModifierNodeElement
+import androidx.compose.ui.node.invalidateDraw
+import androidx.compose.ui.node.invalidateMeasurement
+import androidx.compose.ui.platform.InspectorInfo
 import androidx.compose.ui.unit.Constraints
 import androidx.compose.ui.unit.constrainHeight
 import androidx.compose.ui.unit.constrainWidth
 import kotlin.math.roundToInt
 
 /**
- * A custom [paint] modifier used by [Content].
+ * A custom [paint] modifier used by [AsyncImage] and [SubcomposeAsyncImage].
  */
-internal data class ContentPainterModifier(
+internal data class ContentPainterElement(
     private val painter: Painter,
     private val alignment: Alignment,
     private val contentScale: ContentScale,
     private val alpha: Float,
     private val colorFilter: ColorFilter?,
-) : LayoutModifier, DrawModifier, InspectorValueInfo(
-    debugInspectorInfo {
+) : ModifierNodeElement<ContentPainterNode>() {
+
+    override fun create(): ContentPainterNode {
+        return ContentPainterNode(
+            painter = painter,
+            alignment = alignment,
+            contentScale = contentScale,
+            alpha = alpha,
+            colorFilter = colorFilter,
+        )
+    }
+
+    override fun update(node: ContentPainterNode) {
+        val intrinsicsChanged = node.painter.intrinsicSize != painter.intrinsicSize
+
+        node.painter = painter
+        node.alignment = alignment
+        node.contentScale = contentScale
+        node.alpha = alpha
+        node.colorFilter = colorFilter
+
+        // Only remeasure if intrinsics have changed.
+        if (intrinsicsChanged) {
+            node.invalidateMeasurement()
+        }
+
+        // Redraw because one of the node properties has changed.
+        node.invalidateDraw()
+    }
+
+    override fun InspectorInfo.inspectableProperties() {
         name = "content"
         properties["painter"] = painter
         properties["alignment"] = alignment
         properties["contentScale"] = contentScale
         properties["alpha"] = alpha
         properties["colorFilter"] = colorFilter
     }
-) {
+}
+
+internal class ContentPainterNode(
+    var painter: Painter,
+    var alignment: Alignment,
+    var contentScale: ContentScale,
+    var alpha: Float,
+    var colorFilter: ColorFilter?,
+) : Modifier.Node(), DrawModifierNode, LayoutModifierNode {
+
+    override val shouldAutoInvalidate get() = false
 
     override fun MeasureScope.measure(
         measurable: Measurable,
-        constraints: Constraints
+        constraints: Constraints,
     ): MeasureResult {
         val placeable = measurable.measure(modifyConstraints(constraints))
         return layout(placeable.width, placeable.height) {
@@ -57,7 +99,7 @@ internal data class ContentPainterModifier(
 
     override fun IntrinsicMeasureScope.minIntrinsicWidth(
         measurable: IntrinsicMeasurable,
-        height: Int
+        height: Int,
     ): Int {
         return if (painter.intrinsicSize.isSpecified) {
             val constraints = Constraints(maxHeight = height)
@@ -71,7 +113,7 @@ internal data class ContentPainterModifier(
 
     override fun IntrinsicMeasureScope.maxIntrinsicWidth(
         measurable: IntrinsicMeasurable,
-        height: Int
+        height: Int,
     ): Int {
         return if (painter.intrinsicSize.isSpecified) {
             val constraints = Constraints(maxHeight = height)
@@ -85,11 +127,12 @@ internal data class ContentPainterModifier(
 
     override fun IntrinsicMeasureScope.minIntrinsicHeight(
         measurable: IntrinsicMeasurable,
-        width: Int
+        width: Int,
     ): Int {
         return if (painter.intrinsicSize.isSpecified) {
             val constraints = Constraints(maxWidth = width)
-            val layoutHeight = measurable.minIntrinsicHeight(modifyConstraints(constraints).maxWidth)
+            val layoutHeight =
+                measurable.minIntrinsicHeight(modifyConstraints(constraints).maxWidth)
             val scaledSize = calculateScaledSize(Size(width.toFloat(), layoutHeight.toFloat()))
             maxOf(scaledSize.height.roundToInt(), layoutHeight)
         } else {
@@ -99,11 +142,12 @@ internal data class ContentPainterModifier(
 
     override fun IntrinsicMeasureScope.maxIntrinsicHeight(
         measurable: IntrinsicMeasurable,
-        width: Int
+        width: Int,
     ): Int {
         return if (painter.intrinsicSize.isSpecified) {
             val constraints = Constraints(maxWidth = width)
-            val layoutHeight = measurable.maxIntrinsicHeight(modifyConstraints(constraints).maxWidth)
+            val layoutHeight =
+                measurable.maxIntrinsicHeight(modifyConstraints(constraints).maxWidth)
             val scaledSize = calculateScaledSize(Size(width.toFloat(), layoutHeight.toFloat()))
             maxOf(scaledSize.height.roundToInt(), layoutHeight)
         } else {
@@ -123,7 +167,7 @@ internal data class ContentPainterModifier(
 
         val srcSize = Size(
             width = intrinsicSize.width.takeOrElse { dstSize.width },
-            height = intrinsicSize.height.takeOrElse { dstSize.height }
+            height = intrinsicSize.height.takeOrElse { dstSize.height },
         )
         val scaleFactor = contentScale.computeScaleFactor(srcSize, dstSize)
         if (!scaleFactor.scaleX.isFinite() || !scaleFactor.scaleY.isFinite()) {
@@ -148,7 +192,7 @@ internal data class ContentPainterModifier(
             if (hasBoundedSize) {
                 return constraints.copy(
                     minWidth = constraints.maxWidth,
-                    minHeight = constraints.maxHeight
+                    minHeight = constraints.maxHeight,
                 )
             } else {
                 return constraints
@@ -179,7 +223,7 @@ internal data class ContentPainterModifier(
         val (scaledWidth, scaledHeight) = calculateScaledSize(Size(dstWidth, dstHeight))
         return constraints.copy(
             minWidth = constraints.constrainWidth(scaledWidth.roundToInt()),
-            minHeight = constraints.constrainHeight(scaledHeight.roundToInt())
+            minHeight = constraints.constrainHeight(scaledHeight.roundToInt()),
         )
     }
 
@@ -188,7 +232,7 @@ internal data class ContentPainterModifier(
         val (dx, dy) = alignment.align(
             size = scaledSize.toIntSize(),
             space = size.toIntSize(),
-            layoutDirection = layoutDirection
+            layoutDirection = layoutDirection,
         )
 
         // Draw the painter.

diff --git a/coil-compose-base/src/main/java/coil/compose/SubcomposeAsyncImage.kt b/coil-compose-base/src/main/java/coil/compose/SubcomposeAsyncImage.kt
@@ -338,13 +338,13 @@ fun SubcomposeAsyncImageScope.SubcomposeAsyncImageContent(
         .contentDescription(contentDescription)
         .run { if (clipToBounds) clipToBounds() else this }
         .then(
-            ContentPainterModifier(
+            ContentPainterElement(
                 painter = painter,
                 alignment = alignment,
                 contentScale = contentScale,
                 alpha = alpha,
-                colorFilter = colorFilter
-            )
+                colorFilter = colorFilter,
+            ),
         ),
     measurePolicy = { _, constraints ->
         layout(constraints.minWidth, constraints.minHeight) {}