First drop for breadcrumb bar

Put on-demand horizontal scrolling in place around a row of command buttons. Nothing in terms of real content configuration yet.

For #8

component/src/desktopMain/kotlin/org/pushingpixels/aurora/component/AuroraBreadcrumbBar.kt

@@ -0,0 +1,234 @@
+/*
+ * Copyright 2020-2022 Aurora, Kirill Grouchnikov
+ *
+ * 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 org.pushingpixels.aurora.component
+
+import androidx.compose.foundation.horizontalScroll
+import androidx.compose.foundation.layout.*
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.drawscope.DrawScope
+import androidx.compose.ui.graphics.painter.Painter
+import androidx.compose.ui.layout.Layout
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.platform.LocalFontLoader
+import androidx.compose.ui.platform.LocalLayoutDirection
+import androidx.compose.ui.text.resolveDefaults
+import androidx.compose.ui.unit.Constraints
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.launch
+import org.pushingpixels.aurora.common.AuroraInternalApi
+import org.pushingpixels.aurora.component.model.*
+import org.pushingpixels.aurora.component.projection.CommandButtonProjection
+import org.pushingpixels.aurora.component.utils.drawArrow
+import org.pushingpixels.aurora.theming.BackgroundAppearanceStrategy
+import org.pushingpixels.aurora.theming.LocalTextStyle
+import org.pushingpixels.aurora.theming.PopupPlacementStrategy
+
+@OptIn(AuroraInternalApi::class)
+@Composable
+fun AuroraBreadcrumbBar(commands: List<Command>, modifier: Modifier) {
+    val density = LocalDensity.current
+    val layoutDirection = LocalLayoutDirection.current
+    val textStyle = LocalTextStyle.current
+    val resourceLoader = LocalFontLoader.current
+
+    val resolvedTextStyle = remember { resolveDefaults(textStyle, layoutDirection) }
+
+    val scrollerPresentationModel = CommandButtonPresentationModel(
+        presentationState = CommandButtonPresentationState.Small,
+        contentPadding = PaddingValues(2.dp),
+        actionFireTrigger = ActionFireTrigger.OnRollover,
+        autoRepeatAction = true,
+        autoRepeatInitialInterval = 250L,
+        autoRepeatSubsequentInterval = 100L
+    )
+    val scrollerLayoutManager = scrollerPresentationModel.presentationState.createLayoutManager(
+        layoutDirection = layoutDirection,
+        density = density,
+        textStyle = resolvedTextStyle,
+        resourceLoader = resourceLoader
+    )
+
+    val contentPresentationModel = CommandButtonPresentationModel(
+        presentationState = CommandButtonPresentationState.Medium,
+        backgroundAppearanceStrategy = BackgroundAppearanceStrategy.Flat
+    )
+    val contentLayoutManager = contentPresentationModel.presentationState.createLayoutManager(
+        layoutDirection = layoutDirection,
+        density = density,
+        textStyle = resolvedTextStyle,
+        resourceLoader = resourceLoader
+    )
+
+    val stateHorizontal = rememberScrollState(0)
+    val scope = rememberCoroutineScope()
+    val scrollAmount = 12.dp.value * density.density
+
+    val leftScrollerCommand = Command(text = "",
+        icon = object : Painter() {
+            override val intrinsicSize: Size = Size.Unspecified
+
+            override fun DrawScope.onDraw() {
+                drawArrow(
+                    drawScope = this,
+                    width = ComboBoxSizingConstants.DefaultComboBoxArrowHeight.toPx(),
+                    height = ComboBoxSizingConstants.DefaultComboBoxArrowWidth.toPx(),
+                    strokeWidth = 2.0.dp.toPx(),
+                    direction = PopupPlacementStrategy.Startward,
+                    layoutDirection = layoutDirection,
+                    color = Color.Red
+                )
+            }
+        },
+        isActionEnabled = (stateHorizontal.value > 0),
+        action = {
+            scope.launch {
+                stateHorizontal.scrollTo(
+                    (stateHorizontal.value - scrollAmount.toInt()).coerceAtLeast(0)
+                )
+            }
+        })
+    val rightScrollerCommand = Command(text = "",
+        icon = object : Painter() {
+            override val intrinsicSize: Size = Size.Unspecified
+
+            override fun DrawScope.onDraw() {
+                drawArrow(
+                    drawScope = this,
+                    width = ComboBoxSizingConstants.DefaultComboBoxArrowHeight.toPx(),
+                    height = ComboBoxSizingConstants.DefaultComboBoxArrowWidth.toPx(),
+                    strokeWidth = 2.0.dp.toPx(),
+                    direction = PopupPlacementStrategy.Endward,
+                    layoutDirection = layoutDirection,
+                    color = Color.Red
+                )
+            }
+        },
+        isActionEnabled = (stateHorizontal.value < stateHorizontal.maxValue),
+        action = {
+            scope.launch {
+                stateHorizontal.scrollTo(
+                    (stateHorizontal.value + scrollAmount.toInt()).coerceAtMost(
+                        stateHorizontal.maxValue
+                    )
+                )
+            }
+        })
+
+    Layout(modifier = modifier.fillMaxWidth(),
+        content = {
+            // Leftwards scroller
+            CommandButtonProjection(
+                contentModel = leftScrollerCommand,
+                presentationModel = scrollerPresentationModel
+            ).project()
+
+            Box(modifier = Modifier.horizontalScroll(stateHorizontal)) {
+                Row(modifier = Modifier.fillMaxWidth().wrapContentHeight()) {
+                    for (command in commands) {
+                        CommandButtonProjection(
+                            contentModel = command,
+                            presentationModel = contentPresentationModel
+                        ).project()
+                    }
+                }
+            }
+
+            // Rightwards scroller
+            CommandButtonProjection(
+                contentModel = rightScrollerCommand,
+                presentationModel = scrollerPresentationModel
+            ).project()
+
+        },
+        measurePolicy = { measurables, constraints ->
+            val leftScrollerMeasurable = measurables[0]
+            val contentMeasurable = measurables[1]
+            val rightScrollerMeasurable = measurables[2]
+
+            val leftScrollerPreLayoutInfo =
+                scrollerLayoutManager.getPreLayoutInfo(
+                    leftScrollerCommand,
+                    scrollerPresentationModel
+                )
+            val leftScrollerSize = scrollerLayoutManager.getPreferredSize(
+                leftScrollerCommand, scrollerPresentationModel, leftScrollerPreLayoutInfo
+            )
+
+            val rightScrollerPreLayoutInfo =
+                scrollerLayoutManager.getPreLayoutInfo(
+                    rightScrollerCommand,
+                    scrollerPresentationModel
+                )
+            val rightScrollerSize = scrollerLayoutManager.getPreferredSize(
+                rightScrollerCommand, scrollerPresentationModel, rightScrollerPreLayoutInfo
+            )
+
+            var boxRequiredWidth = 0.0f
+            var boxHeight = 0
+            for (command in commands) {
+                val commandPreLayoutInfo =
+                    contentLayoutManager.getPreLayoutInfo(
+                        command,
+                        contentPresentationModel
+                    )
+                val commandSize = contentLayoutManager.getPreferredSize(
+                    command, contentPresentationModel, commandPreLayoutInfo
+                )
+                boxRequiredWidth += commandSize.width
+                boxHeight = commandSize.height.toInt()
+            }
+
+            val needScrollers = (boxRequiredWidth > constraints.maxWidth)
+            val contentWidth = if (needScrollers) constraints.maxWidth -
+                    leftScrollerSize.width - rightScrollerSize.width
+            else constraints.maxWidth
+
+            val leftScrollerPlaceable = leftScrollerMeasurable.measure(
+                Constraints.fixed(
+                    width = if (needScrollers) leftScrollerSize.width.toInt() else 0,
+                    height = boxHeight
+                )
+            )
+            val rightScrollerPlaceable = rightScrollerMeasurable.measure(
+                Constraints.fixed(
+                    width = if (needScrollers) rightScrollerSize.width.toInt() else 0,
+                    height = boxHeight
+                )
+            )
+            val contentPlaceable = contentMeasurable.measure(
+                Constraints.fixed(contentWidth.toInt(), boxHeight)
+            )
+
+            layout(width = constraints.maxWidth, height = boxHeight) {
+                if (leftScrollerPlaceable.width > 0) {
+                    leftScrollerPlaceable.placeRelative(0, 0)
+                }
+                if (rightScrollerPlaceable.width > 0) {
+                    rightScrollerPlaceable.placeRelative(
+                        constraints.maxWidth - rightScrollerPlaceable.width,
+                        0
+                    )
+                }
+                contentPlaceable.placeRelative(leftScrollerPlaceable.width, 0)
+            }
+        })
+}

demo/src/desktopMain/kotlin/org/pushingpixels/aurora/demo/AuroraBreadcrumbBarDemo.kt

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2020-2022 Aurora, Kirill Grouchnikov
+ *
+ * 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 org.pushingpixels.aurora.demo
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.window.WindowPlacement
+import androidx.compose.ui.window.WindowPosition
+import androidx.compose.ui.window.rememberWindowState
+import org.pushingpixels.aurora.common.AuroraInternalApi
+import org.pushingpixels.aurora.component.AuroraBreadcrumbBar
+import org.pushingpixels.aurora.component.model.Command
+import org.pushingpixels.aurora.demo.svg.radiance_menu
+import org.pushingpixels.aurora.demo.svg.tango.*
+import org.pushingpixels.aurora.theming.IconFilterStrategy
+import org.pushingpixels.aurora.theming.marinerSkin
+import org.pushingpixels.aurora.window.AuroraApplicationScope
+import org.pushingpixels.aurora.window.AuroraWindow
+import org.pushingpixels.aurora.window.auroraApplication
+
+fun main() = auroraApplication {
+    val state = rememberWindowState(
+        placement = WindowPlacement.Floating,
+        position = WindowPosition.Aligned(Alignment.Center),
+        size = DpSize(400.dp, 200.dp)
+    )
+    val skin = mutableStateOf(marinerSkin())
+
+    AuroraWindow(
+        skin = skin,
+        title = "Aurora Demo",
+        icon = radiance_menu(),
+        iconFilterStrategy = IconFilterStrategy.ThemedFollowText,
+        state = state,
+        undecorated = true,
+        onCloseRequest = ::exitApplication,
+    ) {
+        BreadcrumbContent()
+    }
+}
+
+@Composable
+fun AuroraApplicationScope.BreadcrumbContent() {
+    val icons = arrayOf(
+        accessories_text_editor(),
+        computer(),
+        drive_harddisk(),
+        emblem_system(),
+        font_x_generic(),
+        help_browser(),
+        media_floppy(),
+        preferences_desktop_locale_2(),
+        user_home()
+    )
+    val commands = icons.map {
+        Command(
+            text = "sample",
+            icon = it,
+            action = { println("Activated!") }
+        )
+    }
+
+    Box(modifier = Modifier.fillMaxSize()) {
+        AuroraBreadcrumbBar(
+            commands = commands,
+            modifier = Modifier.fillMaxWidth()
+        )
+    }
+}
+
+
+
+
+