MaterialTheme.kt
/*
* Copyright 2023 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
*
* http://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 androidx.wear.compose.material3
import androidx.compose.foundation.LocalIndication
import androidx.compose.foundation.text.selection.LocalTextSelectionColors
import androidx.compose.material.ripple.LocalRippleTheme
import androidx.compose.material.ripple.RippleTheme
import androidx.compose.material.ripple.rememberRipple
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.Immutable
import androidx.compose.runtime.ReadOnlyComposable
import androidx.compose.runtime.remember
/**
* MaterialTheme defines the styling principles from the Wear Material3 design specification
* which extends the Material design specification.
*
* Wear Material components from package/sub-packages in [androidx.wear.compose.material3]
* use values provided here when retrieving default values.
*
* TODO(b/273543423) Update references to Material3 design specs
*
* All values may be set by providing this component with the [colors][ColorScheme],
* [typography][Typography], and [shapes][Shapes] attributes. Use this to configure the
* overall theme of elements within this MaterialTheme.
*
* Any values that are not set will inherit the current value from the theme, falling back to the
* defaults if there is no parent MaterialTheme. This allows using a MaterialTheme at the
* top of your application, and then separate MaterialTheme(s) for different screens / parts of
* your UI, overriding only the parts of the theme definition that need to change.
*
* For more information, see the
* [Theming](https://developer.android.com/training/wearables/components/theme)
* guide.
*
* @param colorScheme A complete definition of the Wear Material Color theme for this hierarchy
* @param typography A set of text styles to be used as this hierarchy's typography system
* @param shapes A set of shapes to be used by the components in this hierarchy
*/
@Composable
public fun MaterialTheme(
colorScheme: ColorScheme = MaterialTheme.colorScheme,
typography: Typography = MaterialTheme.typography,
shapes: Shapes = MaterialTheme.shapes,
content: @Composable () -> Unit
) {
val rememberedColors = remember {
// Explicitly creating a new object here so we don't mutate the initial [colors]
// provided, and overwrite the values set in it.
colorScheme.copy()
}.apply { updateColorSchemeFrom(colorScheme) }
val rippleIndication = rememberRipple()
val selectionColors = rememberTextSelectionColors(rememberedColors)
CompositionLocalProvider(
LocalColors provides rememberedColors,
LocalShapes provides shapes,
LocalTypography provides typography,
LocalContentAlpha provides ContentAlpha.high,
LocalIndication provides rippleIndication,
LocalRippleTheme provides MaterialRippleTheme,
LocalTextSelectionColors provides selectionColors,
) {
ProvideTextStyle(value = typography.bodyLarge, content = content)
}
}
public object MaterialTheme {
public val colorScheme: ColorScheme
@ReadOnlyComposable
@Composable
get() = LocalColors.current
public val typography: Typography
@ReadOnlyComposable
@Composable
get() = LocalTypography.current
public val shapes: Shapes
@ReadOnlyComposable
@Composable
get() = LocalShapes.current
}
@Immutable
private object MaterialRippleTheme : RippleTheme {
@Composable
override fun defaultColor() = RippleTheme.defaultRippleColor(
contentColor = LocalContentColor.current,
lightTheme = false
)
@Composable
override fun rippleAlpha() = RippleTheme.defaultRippleAlpha(
contentColor = LocalContentColor.current,
lightTheme = false
)
}