Support RTL in drawTimeAxis

davidtakac · Jan 29, 2025 · 012493e · 012493e
1 parent 5680e78
commit 012493e
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Showing 3 changed files with 25 additions and 7 deletions.
diff --git a/app/src/main/java/com/davidtakac/bura/graphs/common/DrawTimeAxis.kt b/app/src/main/java/com/davidtakac/bura/graphs/common/DrawTimeAxis.kt
@@ -17,15 +17,20 @@ import androidx.compose.ui.graphics.PathEffect
 import androidx.compose.ui.graphics.drawscope.DrawScope
 import androidx.compose.ui.text.TextMeasurer
 import androidx.compose.ui.text.drawText
+import androidx.compose.ui.unit.LayoutDirection
 import java.time.LocalTime
 
 fun DrawScope.drawTimeAxis(
     measurer: TextMeasurer,
     args: GraphArgs,
+    layoutDirection: LayoutDirection = LayoutDirection.Ltr,
     onStepDrawn: (index: Int, x: Float) -> Unit
 ) {
     for (i in 0..24) {
-        val x = ((i.toFloat() / 24) * (size.width - args.endGutter - args.startGutter)) + args.startGutter
+        val xPercent = if (layoutDirection == LayoutDirection.Ltr) i / 24f else 1 - (i / 24f)
+        val xOffset = if (layoutDirection == LayoutDirection.Ltr) args.startGutter else args.endGutter - args.startGutter
+        val plotWidth = size.width - args.endGutter - args.startGutter
+        val x = xPercent * plotWidth + xOffset
         fun drawTimeHelperLine(onEdge: Boolean) {
             drawLine(
                 color = args.axisColor,
@@ -43,13 +48,22 @@ fun DrawScope.drawTimeAxis(
             )
             drawTimeHelperLine(onEdge = i == 0 || i == 24)
             if (i != 24) {
+                val textTopLeftX =
+                    if (layoutDirection == LayoutDirection.Ltr) x + args.bottomAxisTextPaddingStart
+                    else x - label.size.width - args.bottomAxisTextPaddingStart
+                val textTopLeftXMin =
+                    if (layoutDirection == LayoutDirection.Ltr) args.startGutter + args.textPaddingMinHorizontal
+                    else args.endGutter + args.textPaddingMinHorizontal
+                val textTopLeftXMax =
+                    if (layoutDirection == LayoutDirection.Ltr) size.width - args.endGutter - label.size.width - args.textPaddingMinHorizontal
+                    else size.width - args.startGutter - label.size.width - args.textPaddingMinHorizontal
                 drawText(
                     textLayoutResult = label,
                     color = args.axisColor,
                     topLeft = Offset(
-                        x = (x + args.bottomAxisTextPaddingLeft).coerceIn(
-                            minimumValue = args.startGutter + args.textPaddingMinHorizontal,
-                            maximumValue = size.width - args.endGutter - label.size.width - args.textPaddingMinHorizontal
+                        x = textTopLeftX.coerceIn(
+                            minimumValue = textTopLeftXMin,
+                            maximumValue = textTopLeftXMax
                         ),
                         y = size.height - args.bottomGutter + args.bottomAxisTextPaddingTop
                     )

diff --git a/app/src/main/java/com/davidtakac/bura/graphs/common/GraphArgs.kt b/app/src/main/java/com/davidtakac/bura/graphs/common/GraphArgs.kt
@@ -44,7 +44,7 @@ data class GraphArgs(
     val axisTextStyle: TextStyle,
     val axisColor: Color,
     val axisDashIntervals: List<Float>,
-    val bottomAxisTextPaddingLeft: Float,
+    val bottomAxisTextPaddingStart: Float,
     val bottomAxisTextPaddingTop: Float,
     val endAxisTextPaddingStart: Float,
     val pointTextPaddingBottom: Float,
@@ -85,11 +85,11 @@ data class GraphArgs(
                 axisTextStyle = typography.bodySmall,
                 axisColor = colorScheme.onSurfaceVariant,
                 axisDashIntervals = listOf(4.dp, 2.dp).map { it.toPx() },
-                bottomAxisTextPaddingLeft = axisTextPadding,
+                bottomAxisTextPaddingStart = axisTextPadding,
                 bottomAxisTextPaddingTop = axisTextPadding,
                 endAxisTextPaddingStart = axisTextPadding,
                 pointTextPaddingBottom = axisTextPadding,
-                textPaddingMinHorizontal = 2.dp.toPx(),
+                textPaddingMinHorizontal = axisTextPadding,
                 numberFormat = numberFormat,
                 axisTimeFormatter = dateTimeFormatter,
                 pointCenterRadius = pointCenterRadius,

diff --git a/app/src/main/java/com/davidtakac/bura/graphs/temperature/TemperatureGraph.kt b/app/src/main/java/com/davidtakac/bura/graphs/temperature/TemperatureGraph.kt
@@ -75,6 +75,7 @@ fun TemperatureGraph(
     val context = LocalContext.current
     val measurer = rememberTextMeasurer()
     val plotColors = AppTheme.colors.temperatureColors(minCelsius, maxCelsius)
+    val layoutDirection = LocalLayoutDirection.current
     Canvas(modifier) {
         drawTempAxis(
             unit = absMinTemp.unit,
@@ -91,6 +92,7 @@ fun TemperatureGraph(
             context = context,
             measurer = measurer,
             plotColors = plotColors,
+            layoutDirection = layoutDirection,
             args = args
         )
     }
@@ -103,6 +105,7 @@ private fun DrawScope.drawHorizontalAxisAndPlot(
     maxCelsius: Double,
     context: Context,
     measurer: TextMeasurer,
+    layoutDirection: LayoutDirection,
     args: GraphArgs
 ) {
     val iconSize = 24.dp.toPx()
@@ -125,6 +128,7 @@ private fun DrawScope.drawHorizontalAxisAndPlot(
 
     drawTimeAxis(
         measurer = measurer,
+        layoutDirection = layoutDirection,
         args = args
     ) { i, x ->
         // Temperature line