diff --git a/packages/flutter/lib/src/material/slider_theme.dart b/packages/flutter/lib/src/material/slider_theme.dart index a4b3bef53c..bafbc5fa95 100644 --- a/packages/flutter/lib/src/material/slider_theme.dart +++ b/packages/flutter/lib/src/material/slider_theme.dart @@ -1840,10 +1840,17 @@ mixin BaseSliderTrackShape { final double thumbWidth = sliderTheme.thumbShape!.getPreferredSize(isEnabled, isDiscrete).width; final double overlayWidth = sliderTheme.overlayShape!.getPreferredSize(isEnabled, isDiscrete).width; - final double trackHeight = sliderTheme.trackHeight!; + double trackHeight = sliderTheme.trackHeight!; assert(overlayWidth >= 0); assert(trackHeight >= 0); + // If the track colors are transparent, then override only the track height + // to maintain overall Slider width. + if (sliderTheme.activeTrackColor == Colors.transparent && + sliderTheme.inactiveTrackColor == Colors.transparent) { + trackHeight = 0; + } + final double trackLeft = offset.dx + (sliderTheme.padding == null ? math.max(overlayWidth / 2, thumbWidth / 2) : 0); final double trackTop = offset.dy + (parentBox.size.height - trackHeight) / 2; diff --git a/packages/flutter/test/material/slider_theme_test.dart b/packages/flutter/test/material/slider_theme_test.dart index 8ba78b2aab..7fcf741434 100644 --- a/packages/flutter/test/material/slider_theme_test.dart +++ b/packages/flutter/test/material/slider_theme_test.dart @@ -3009,6 +3009,47 @@ void main() { ); }); + // Regression test for https://github.com/flutter/flutter/issues/161210 + testWidgets( + 'Slider with transparent track colors and custom track height can reach extreme ends', + (WidgetTester tester) async { + const double sliderPadding = 24.0; + final ThemeData theme = ThemeData( + sliderTheme: const SliderThemeData( + trackHeight: 100, + activeTrackColor: Colors.transparent, + inactiveTrackColor: Colors.transparent, + ), + ); + + Widget buildSlider({required double value}) { + return MaterialApp( + theme: theme, + home: Material( + child: SizedBox(width: 300, child: Slider(value: value, onChanged: (double value) {})), + ), + ); + } + + await tester.pumpWidget(buildSlider(value: 0)); + + MaterialInkController material = Material.of(tester.element(find.byType(Slider))); + + expect( + material, + paints..circle(x: sliderPadding, y: 300.0, color: theme.colorScheme.primary), + ); + + await tester.pumpWidget(buildSlider(value: 1)); + + material = Material.of(tester.element(find.byType(Slider))); + expect( + material, + paints..circle(x: 800.0 - sliderPadding, y: 300.0, color: theme.colorScheme.primary), + ); + }, + ); + group('Material 2', () { // These tests are only relevant for Material 2. Once Material 2 // support is deprecated and the APIs are removed, these tests