Add TimeMeasurer for Spa

/*

 * Copyright (C) 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

 *

 *      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.

 */

@file:OptIn(ExperimentalTime::class)

package com.android.settingslib.spa.framework.compose

import android.util.Log

import androidx.compose.runtime.Composable

import androidx.compose.runtime.remember

import kotlin.time.ExperimentalTime

import kotlin.time.TimeSource

const val ENABLE_MEASURE_TIME = false

interface TimeMeasurer {

    fun log(msg: String) {}

    fun logFirst(msg: String) {}

    companion object {

        private object EmptyTimeMeasurer : TimeMeasurer

        @Composable

        fun rememberTimeMeasurer(tag: String): TimeMeasurer = remember {

            if (ENABLE_MEASURE_TIME) TimeMeasurerImpl(tag) else EmptyTimeMeasurer

        }

    }

}

private class TimeMeasurerImpl(private val tag: String) : TimeMeasurer {

    private val mark = TimeSource.Monotonic.markNow()

    private val msgLogged = mutableSetOf<String>()

    override fun log(msg: String) {

        Log.d(tag, "Timer $msg: ${mark.elapsedNow()}")

    }

    override fun logFirst(msg: String) {

        if (msgLogged.add(msg)) {

            Log.d(tag, "Timer $msg: ${mark.elapsedNow()}")

        }

    }

}

import androidx.compose.ui.res.stringResource

import androidx.lifecycle.viewmodel.compose.viewModel

import com.android.settingslib.spa.framework.compose.LogCompositions

import com.android.settingslib.spa.framework.compose.TimeMeasurer.Companion.rememberTimeMeasurer

import com.android.settingslib.spa.framework.compose.toState

import com.android.settingslib.spa.framework.theme.SettingsDimension

import com.android.settingslib.spa.widget.ui.PlaceholderTitle

    listModel: AppListModel<T>,

    appItem: @Composable (itemState: AppListItemModel<T>) -> Unit,

) {

    val timeMeasurer = rememberTimeMeasurer(TAG)

    appListData.value?.let { (list, option) ->

        timeMeasurer.logFirst("app list first loaded")

        if (list.isEmpty()) {

            PlaceholderTitle(stringResource(R.string.no_applications))

            return