FLUT-897866-[others][feature]: positive and negative slider

Author: Kaviyarasansf4298

lib/main.dart

@@ -0,0 +1,144 @@
+import 'package:flutter/material.dart';
+import 'package:syncfusion_flutter_sliders/sliders.dart';
+import 'package:syncfusion_flutter_core/theme.dart';
+
+void main() {
+  runApp(const MyApp());
+}
+
+class MyApp extends StatelessWidget {
+  const MyApp({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const MaterialApp(
+      debugShowCheckedModeBanner: false,
+      home: MyHomePage(),
+    );
+  }
+}
+
+class MyHomePage extends StatefulWidget {
+  const MyHomePage({super.key});
+
+  @override
+  State<MyHomePage> createState() => _MyHomePageState();
+}
+
+class _MyHomePageState extends State<MyHomePage> {
+  double _value = 0.0;
+  SfSlider _buildHorizontalSlider() {
+    return SfSlider(
+      showTicks: true,
+      showLabels: true,
+      min: -10,
+      max: 10,
+      interval: 5,
+      value: _value,
+      thumbShape: _CustomThumbShape(type: SliderType.horizontal, value: _value),
+      onChanged: (dynamic value) {
+        setState(
+          () {
+            _value = value;
+          },
+        );
+      },
+    );
+  }
+
+  SfSlider _buildVerticalSlider() {
+    return SfSlider.vertical(
+      showTicks: true,
+      showLabels: true,
+      min: -10,
+      max: 10,
+      interval: 5,
+      value: _value,
+      thumbShape: _CustomThumbShape(type: SliderType.vertical, value: _value),
+      onChanged: (dynamic value) {
+        setState(
+          () {
+            _value = value;
+          },
+        );
+      },
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final SfColorScheme colorScheme = SfTheme.colorScheme(context);
+    return Scaffold(
+      body: Center(
+        child: SfSliderTheme(
+          data: SfSliderThemeData(
+            activeTrackColor: colorScheme.primary[61],
+            trackCornerRadius: 7.5,
+            activeTrackHeight: 10,
+            inactiveTrackHeight: 10,
+          ),
+          child: _buildHorizontalSlider(),
+        ),
+      ),
+    );
+  }
+}
+
+class _CustomThumbShape extends SfThumbShape {
+  _CustomThumbShape({required this.type, required this.value});
+  final SliderType type;
+  final double value;
+
+  @override
+  void paint(PaintingContext context, Offset center,
+      {required RenderBox parentBox,
+      required RenderBox? child,
+      required SfSliderThemeData themeData,
+      SfRangeValues? currentValues,
+      dynamic currentValue,
+      required Paint? paint,
+      required Animation<double> enableAnimation,
+      required TextDirection textDirection,
+      required SfThumb? thumb}) {
+    final Paint thumbPaint = Paint();
+    final Rect? rect;
+    final Offset trackCenter =
+        Offset(parentBox.size.width / 2, parentBox.size.height / 2);
+    final halfTrackHeight = themeData.activeTrackHeight / 2;
+    final x = center.dx;
+    final y = center.dy;
+    if (type == SliderType.vertical) {
+      rect = Rect.fromLTRB(
+        x - halfTrackHeight,
+        y,
+        x + halfTrackHeight,
+        parentBox.size.height / 2,
+      );
+    } else {
+      rect = Rect.fromLTRB(
+        x,
+        y - halfTrackHeight,
+        trackCenter.dx,
+        y + halfTrackHeight,
+      );
+    }
+
+    thumbPaint
+      ..color =
+          value < 0 ? const Color(0XFFC62828) : Colors.orange.withOpacity(0.850)
+      ..style = PaintingStyle.fill
+      ..strokeWidth = themeData.activeTrackHeight;
+
+    context.canvas.drawRect(rect, thumbPaint);
+    super.paint(context, center,
+        parentBox: parentBox,
+        child: child,
+        themeData: themeData,
+        paint: thumbPaint,
+        enableAnimation: enableAnimation,
+        textDirection: textDirection,
+        thumb: thumb);
+  }
+}
+
+enum SliderType { vertical, horizontal }