Added Placeholder for Material3 Themes

gradle/libs.versions.toml

@@ -17,6 +17,7 @@ coil = "1.3.2"
 androidxtest = "1.4.0"
 androidxnavigation = "2.5.0-rc02"
 androidxWindow = "1.0.0"
+material3 = "1.0.0-beta01"
 
 [libraries]
 compose-ui-ui = { module = "androidx.compose.ui:ui", version.ref = "compose" }
@@ -28,6 +29,7 @@ compose-ui-test-manifest = { module = "androidx.compose.ui:ui-test-manifest", ve
 compose-foundation-foundation = { module = "androidx.compose.foundation:foundation", version.ref = "compose" }
 compose-foundation-layout = { module = "androidx.compose.foundation:foundation-layout", version.ref = "compose" }
 compose-material-material = { module = "androidx.compose.material:material", version.ref = "compose" }
+compose-material-material3 = { module = "androidx.compose.material3:material3", version.ref = "material3" }
 compose-material-iconsext = { module = "androidx.compose.material:material-icons-extended", version.ref = "compose" }
 compose-animation-animation = { module = "androidx.compose.animation:animation", version.ref = "compose" }
 

placeholder-material3/README.md

@@ -0,0 +1,21 @@
+# Placeholder for Jetpack Compose (Material3)
+
+[![Maven Central](https://img.shields.io/maven-central/v/com.google.accompanist/accompanist-placeholder)](https://search.maven.org/search?q=g:com.google.accompanist)
+
+For more information, visit the documentation: https://google.github.io/accompanist/placeholder
+
+## Download
+
+```groovy
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation "com.google.accompanist:accompanist-placeholder-material3:<version>"
+}
+```
+
+Snapshots of the development version are available in [Sonatype's `snapshots` repository][snap]. These are updated on every commit.
+
+  [snap]: https://oss.sonatype.org/content/repositories/snapshots/com/google/accompanist/accompanist-placeholder-material3/

placeholder-material3/api/current.api

@@ -0,0 +1,17 @@
+// Signature format: 4.0
+package com.google.accompanist.placeholder.material3 {
+
+  public final class PlaceholderHighlightKt {
+    method @androidx.compose.runtime.Composable public static com.google.accompanist.placeholder.PlaceholderHighlight fade(com.google.accompanist.placeholder.PlaceholderHighlight.Companion, optional androidx.compose.animation.core.InfiniteRepeatableSpec<java.lang.Float> animationSpec);
+    method @androidx.compose.runtime.Composable public static com.google.accompanist.placeholder.PlaceholderHighlight shimmer(com.google.accompanist.placeholder.PlaceholderHighlight.Companion, optional androidx.compose.animation.core.InfiniteRepeatableSpec<java.lang.Float> animationSpec, optional @FloatRange(from=0.0, to=1.0) float progressForMaxAlpha);
+  }
+
+  public final class PlaceholderKt {
+    method @androidx.compose.runtime.Composable public static long color(com.google.accompanist.placeholder.PlaceholderDefaults, optional long backgroundColor, optional long contentColor, optional float contentAlpha);
+    method @androidx.compose.runtime.Composable public static long fadeHighlightColor(com.google.accompanist.placeholder.PlaceholderDefaults, optional long backgroundColor, optional float alpha);
+    method public static androidx.compose.ui.Modifier placeholder(androidx.compose.ui.Modifier, boolean visible, optional long color, optional androidx.compose.ui.graphics.Shape? shape, optional com.google.accompanist.placeholder.PlaceholderHighlight? highlight, optional kotlin.jvm.functions.Function1<? super androidx.compose.animation.core.Transition.Segment<java.lang.Boolean>,? extends androidx.compose.animation.core.FiniteAnimationSpec<java.lang.Float>> placeholderFadeTransitionSpec, optional kotlin.jvm.functions.Function1<? super androidx.compose.animation.core.Transition.Segment<java.lang.Boolean>,? extends androidx.compose.animation.core.FiniteAnimationSpec<java.lang.Float>> contentFadeTransitionSpec);
+    method @androidx.compose.runtime.Composable public static long shimmerHighlightColor(com.google.accompanist.placeholder.PlaceholderDefaults, optional long backgroundColor, optional float alpha);
+  }
+
+}
+

placeholder-material3/build.gradle

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+plugins {
+    id 'com.android.library'
+    id 'kotlin-android'
+    id 'org.jetbrains.dokka'
+}
+
+kotlin {
+    explicitApi()
+}
+
+android {
+    compileSdkVersion 33
+
+    defaultConfig {
+        minSdkVersion 21
+        // targetSdkVersion has no effect for libraries. This is only used for the test APK
+        targetSdkVersion 33
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    buildFeatures {
+        buildConfig false
+        compose true
+    }
+
+    composeOptions {
+        kotlinCompilerExtensionVersion libs.versions.composeCompiler.get()
+    }
+
+    lintOptions {
+        textReport true
+        textOutput 'stdout'
+        // We run a full lint analysis as build part in CI, so skip vital checks for assemble tasks
+        checkReleaseBuilds false
+    }
+
+    packagingOptions {
+        // Some of the META-INF files conflict with coroutines-test. Exclude them to enable
+        // our test APK to build (has no effect on our AARs)
+        excludes += "/META-INF/AL2.0"
+        excludes += "/META-INF/LGPL2.1"
+    }
+
+    testOptions {
+        unitTests {
+            includeAndroidResources = true
+        }
+        animationsDisabled true
+    }
+}
+
+dependencies {
+    implementation libs.compose.material.material3
+    api project(':placeholder')
+    implementation libs.napier
+    implementation libs.kotlin.coroutines.android
+
+    // ======================
+    // Test dependencies
+    // ======================
+
+    androidTestImplementation libs.junit
+    androidTestImplementation libs.truth
+
+    androidTestImplementation libs.compose.ui.test.junit4
+    androidTestImplementation libs.compose.ui.test.manifest
+    androidTestImplementation libs.compose.foundation.foundation
+
+    androidTestImplementation libs.androidx.test.core
+    androidTestImplementation libs.androidx.test.rules
+    androidTestImplementation libs.androidx.test.runner
+}
+
+apply plugin: "com.vanniktech.maven.publish"

placeholder-material3/gradle.properties

@@ -0,0 +1,3 @@
+POM_ARTIFACT_ID=accompanist-placeholder-material3
+POM_NAME=Accompanist Placeholder Material3
+POM_PACKAGING=aar

placeholder-material3/src/main/AndroidManifest.xml

@@ -0,0 +1,18 @@
+<!--
+  ~ Copyright 2021 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      https://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<manifest package="com.google.accompanist.placeholder.material3">
+</manifest>

placeholder-material3/src/main/java/com/google/accompanist/placeholder/material3/Placeholder.kt

@@ -0,0 +1,125 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.accompanist.placeholder.material3
+
+import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.core.Transition
+import androidx.compose.animation.core.spring
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.contentColorFor
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.composed
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Shape
+import androidx.compose.ui.graphics.compositeOver
+import androidx.compose.ui.graphics.isSpecified
+import com.google.accompanist.placeholder.PlaceholderDefaults
+import com.google.accompanist.placeholder.PlaceholderHighlight
+import com.google.accompanist.placeholder.placeholder
+
+/**
+ * Returns the value used as the the `color` parameter value on [Modifier.placeholder].
+ *
+ * @param backgroundColor The current background color of the layout. Defaults to
+ * `MaterialTheme.colorScheme.surface`.
+ * @param contentColor The content color to be used on top of [backgroundColor].
+ * @param contentAlpha The alpha component to set on [contentColor] when compositing the color
+ * on top of [backgroundColor]. Defaults to `0.1f`.
+ */
+@Composable
+fun PlaceholderDefaults.color(
+    backgroundColor: Color = MaterialTheme.colorScheme.surface,
+    contentColor: Color = contentColorFor(backgroundColor),
+    contentAlpha: Float = 0.1f,
+): Color = contentColor.copy(contentAlpha).compositeOver(backgroundColor)
+
+/**
+ * Returns the value used as the the `highlightColor` parameter value of
+ * [PlaceholderHighlight.Companion.fade].
+ *
+ * @param backgroundColor The current background color of the layout. Defaults to
+ * `MaterialTheme.colorScheme.surface`.
+ * @param alpha The alpha component to set on [backgroundColor]. Defaults to `0.3f`.
+ */
+@Composable
+fun PlaceholderDefaults.fadeHighlightColor(
+    backgroundColor: Color = MaterialTheme.colorScheme.surface,
+    alpha: Float = 0.3f,
+): Color = backgroundColor.copy(alpha = alpha)
+
+/**
+ * Returns the value used as the the `highlightColor` parameter value of
+ * [PlaceholderHighlight.Companion.shimmer].
+ *
+ * @param backgroundColor The current background color of the layout. Defaults to
+ * `MaterialTheme.colorScheme.inverseSurface`.
+ * @param alpha The alpha component to set on [backgroundColor]. Defaults to `0.75f`.
+ */
+@Composable
+fun PlaceholderDefaults.shimmerHighlightColor(
+    backgroundColor: Color = MaterialTheme.colorScheme.inverseSurface,
+    alpha: Float = 0.75f,
+): Color {
+    return backgroundColor.copy(alpha = alpha)
+}
+
+/**
+ * Draws some skeleton UI which is typically used whilst content is 'loading'.
+ *
+ * To customize the color and shape of the placeholder, you can use the foundation version of
+ * [Modifier.placeholder], along with the values provided by [PlaceholderDefaults].
+ *
+ * A cross-fade transition will be applied to the content and placeholder UI when the [visible]
+ * value changes. The transition can be customized via the [contentFadeTransitionSpec] and
+ * [placeholderFadeTransitionSpec] parameters.
+ *
+ * You can provide a [PlaceholderHighlight] which runs an highlight animation on the placeholder.
+ * The [shimmer] and [fade] implementations are provided for easy usage.
+ *
+ * You can find more information on the pattern at the Material Theming
+ * [Placeholder UI](https://material.io/design/communication/launch-screen.html#placeholder-ui)
+ * guidelines.
+ *
+ * @param visible whether the placeholder should be visible or not.
+ * @param color the color used to draw the placeholder UI. If [Color.Unspecified] is provided,
+ * the placeholder will use [PlaceholderDefaults.color].
+ * @param shape desired shape of the placeholder. If null is provided the placeholder
+ * will use the small shape set in [MaterialTheme.shapes].
+ * @param highlight optional highlight animation.
+ * @param placeholderFadeTransitionSpec The transition spec to use when fading the placeholder
+ * on/off screen. The boolean parameter defined for the transition is [visible].
+ * @param contentFadeTransitionSpec The transition spec to use when fading the content
+ * on/off screen. The boolean parameter defined for the transition is [visible].
+ */
+fun Modifier.placeholder(
+    visible: Boolean,
+    color: Color = Color.Unspecified,
+    shape: Shape? = null,
+    highlight: PlaceholderHighlight? = null,
+    placeholderFadeTransitionSpec: @Composable Transition.Segment<Boolean>.() -> FiniteAnimationSpec<Float> = { spring() },
+    contentFadeTransitionSpec: @Composable Transition.Segment<Boolean>.() -> FiniteAnimationSpec<Float> = { spring() },
+): Modifier = composed {
+    Modifier.placeholder(
+        visible = visible,
+        color = if (color.isSpecified) color else PlaceholderDefaults.color(),
+        shape = shape ?: MaterialTheme.shapes.small,
+        highlight = highlight,
+        placeholderFadeTransitionSpec = placeholderFadeTransitionSpec,
+        contentFadeTransitionSpec = contentFadeTransitionSpec,
+    )
+}

placeholder-material3/src/main/java/com/google/accompanist/placeholder/material3/PlaceholderHighlight.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.accompanist.placeholder.material3
+
+import androidx.annotation.FloatRange
+import androidx.compose.animation.core.AnimationSpec
+import androidx.compose.animation.core.InfiniteRepeatableSpec
+import androidx.compose.runtime.Composable
+import com.google.accompanist.placeholder.PlaceholderDefaults
+import com.google.accompanist.placeholder.PlaceholderHighlight
+import com.google.accompanist.placeholder.fade
+import com.google.accompanist.placeholder.material3.fadeHighlightColor
+import com.google.accompanist.placeholder.material3.shimmerHighlightColor
+import com.google.accompanist.placeholder.shimmer
+
+/**
+ * Creates a [PlaceholderHighlight] which fades in an appropriate color, using the
+ * given [animationSpec].
+ *
+ * @param animationSpec the [AnimationSpec] to configure the animation.
+ */
+@Composable
+fun PlaceholderHighlight.Companion.fade(
+    animationSpec: InfiniteRepeatableSpec<Float> = PlaceholderDefaults.fadeAnimationSpec,
+): PlaceholderHighlight = PlaceholderHighlight.fade(
+    highlightColor = PlaceholderDefaults.fadeHighlightColor(),
+    animationSpec = animationSpec,
+)
+
+/**
+ * Creates a [PlaceholderHighlight] which 'shimmers', using a default color.
+ *
+ * The highlight starts at the top-start, and then grows to the bottom-end during the animation.
+ * During that time it is also faded in, from 0f..progressForMaxAlpha, and then faded out from
+ * progressForMaxAlpha..1f.
+ *
+ * @param animationSpec the [AnimationSpec] to configure the animation.
+ * @param progressForMaxAlpha The progress where the shimmer should be at it's peak opacity.
+ * Defaults to 0.6f.
+ */
+@Composable
+fun PlaceholderHighlight.Companion.shimmer(
+    animationSpec: InfiniteRepeatableSpec<Float> = PlaceholderDefaults.shimmerAnimationSpec,
+    @FloatRange(from = 0.0, to = 1.0) progressForMaxAlpha: Float = 0.6f,
+): PlaceholderHighlight = PlaceholderHighlight.shimmer(
+    highlightColor = PlaceholderDefaults.shimmerHighlightColor(),
+    animationSpec = animationSpec,
+    progressForMaxAlpha = progressForMaxAlpha,
+)

settings.gradle

@@ -39,6 +39,7 @@ include ':permissions'
 include ':permissions-lint'
 include ':placeholder'
 include ':placeholder-material'
+include ':placeholder-material3'
 include ':flowlayout'
 include ':systemuicontroller'
 include ':swiperefresh'