| /* |
| * 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 |
| * |
| * 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.material |
| |
| import androidx.compose.foundation.progressSemantics |
| import androidx.compose.material.icons.materialIcon |
| import androidx.compose.material.icons.materialPath |
| import androidx.compose.ui.Modifier |
| import androidx.compose.ui.graphics.vector.ImageVector |
| import androidx.compose.ui.semantics.disabled |
| import androidx.compose.ui.semantics.semantics |
| import androidx.compose.ui.semantics.setProgress |
| import androidx.compose.ui.util.lerp |
| import kotlin.math.roundToInt |
| |
| /** |
| * Icons which are used by Range controls like slider and stepper |
| */ |
| internal object RangeIcons { |
| |
| /** |
| * An [ImageVector] with a minus sign. |
| */ |
| val Minus: ImageVector |
| get() = if (_minus != null) _minus!! |
| else { |
| _minus = materialIcon(name = "MinusIcon") { |
| materialPath { |
| moveTo(19.0f, 13.0f) |
| horizontalLineTo(5.0f) |
| verticalLineToRelative(-2.0f) |
| horizontalLineToRelative(14.0f) |
| verticalLineToRelative(2.0f) |
| close() |
| } |
| } |
| _minus!! |
| } |
| |
| private var _minus: ImageVector? = null |
| } |
| |
| /** |
| * Defaults used by range controls like slider and stepper |
| */ |
| internal object RangeDefaults { |
| /** |
| * Calculates value of [currentStep] in [valueRange] depending on number of [steps] |
| */ |
| fun calculateCurrentStepValue( |
| currentStep: Int, |
| steps: Int, |
| valueRange: ClosedFloatingPointRange<Float> |
| ): Float = lerp( |
| valueRange.start, valueRange.endInclusive, |
| currentStep.toFloat() / (steps + 1).toFloat() |
| ).coerceIn(valueRange) |
| |
| /** |
| * Snaps [value] to the closest [step] in the [valueRange] |
| */ |
| fun snapValueToStep( |
| value: Float, |
| valueRange: ClosedFloatingPointRange<Float>, |
| steps: Int |
| ): Int = ((value - valueRange.start) / |
| (valueRange.endInclusive - valueRange.start) * (steps + 1)) |
| .roundToInt().coerceIn(0, steps + 1) |
| } |
| |
| internal fun Modifier.rangeSemantics( |
| step: Int, |
| enabled: Boolean, |
| onValueChange: (Float) -> Unit, |
| valueRange: ClosedFloatingPointRange<Float>, |
| steps: Int |
| ): Modifier = semantics(mergeDescendants = true) { |
| if (!enabled) disabled() |
| setProgress( |
| action = { targetValue -> |
| val newStepIndex = RangeDefaults.snapValueToStep(targetValue, valueRange, steps) |
| if (step == newStepIndex) { |
| false |
| } else { |
| onValueChange(targetValue) |
| true |
| } |
| } |
| ) |
| }.progressSemantics( |
| RangeDefaults.calculateCurrentStepValue(step, steps, valueRange), |
| valueRange, steps |
| ) |
| |
| internal fun IntProgression.stepsNumber(): Int = (last - first) / step - 1 |
