Change implementation method

Author: hello-coder-xu

packages/flutter/lib/src/material/slider.dart

@@ -802,7 +802,9 @@ class _SliderState extends State<Slider> with TickerProviderStateMixin {
     // (which can be defined by activeColor) if the
     // RectangularSliderValueIndicatorShape is used. In all other cases, the
     // value indicator is assumed to be the same as the active color.
-    final SliderComponentShape valueIndicatorShape = sliderTheme.valueIndicatorShape ?? defaultValueIndicatorShape;
+    final SliderComponentShape valueIndicatorShape = widget.label == null
+        ? SliderComponentShape.noThumb
+        : sliderTheme.valueIndicatorShape ?? defaultValueIndicatorShape;
     final Color valueIndicatorColor;
     if (valueIndicatorShape is RectangularSliderValueIndicatorShape) {
       valueIndicatorColor = sliderTheme.valueIndicatorColor ?? Color.alphaBlend(theme.colorScheme.onSurface.withOpacity(0.60), theme.colorScheme.surface.withOpacity(0.90));

packages/flutter/lib/src/material/slider_theme.dart

@@ -3485,10 +3485,6 @@ class _DropSliderValueIndicatorPathPainter {
       return;
     }
     assert(!sizeWithOverflow.isEmpty);
-    if (labelPainter.text == null) {
-      // labelPainter.text is null do not draw anything, so it's safe to just return.
-      return;
-    }
     final double rectangleWidth = _upperRectangleWidth(labelPainter, scale);
     final double horizontalShift = getHorizontalShift(
       parentBox: parentBox,

packages/flutter/test/material/slider_theme_test.dart

@@ -2652,27 +2652,35 @@ void main() {
       (WidgetTester tester) async {
     debugDisableShadows = false;
     try {
-      await tester.pumpWidget(_buildSilderApp());
-
-      final RenderBox valueIndicatorBox =
-          tester.renderObject(find.byType(Overlay));
-
-      // Calculate a specific position on the Slider
-      final Rect sliderRect = tester.getRect(find.byType(Slider));
-      final Offset tapPositionLeft = Offset(
-          sliderRect.left + sliderRect.width * 0.25, sliderRect.center.dy);
-      final Offset tapPositionRight = Offset(
-          sliderRect.left + sliderRect.width * 0.75, sliderRect.center.dy);
-
-      // Tap on the 25% position of the Slider
-      await tester.tapAt(tapPositionLeft);
-      await tester.pumpAndSettle();
-      expect(valueIndicatorBox, paintsExactlyCountTimes(#drawPath, 1));
+      final List<SliderComponentShape> shapes = [
+        const PaddleSliderValueIndicatorShape(),
+        const DropSliderValueIndicatorShape(),
+        const RectangularSliderValueIndicatorShape(),
+      ];
+
+      for (final SliderComponentShape element in shapes) {
+        await tester.pumpWidget(_buildSilderApp(element));
+
+        final RenderBox valueIndicatorBox =
+            tester.renderObject(find.byType(Overlay));
+
+        // Calculate a specific position on the Slider
+        final Rect sliderRect = tester.getRect(find.byType(Slider));
+        final Offset tapPositionLeft = Offset(
+            sliderRect.left + sliderRect.width * 0.25, sliderRect.center.dy);
+        final Offset tapPositionRight = Offset(
+            sliderRect.left + sliderRect.width * 0.75, sliderRect.center.dy);
+
+        // Tap on the 25% position of the Slider
+        await tester.tapAt(tapPositionLeft);
+        await tester.pumpAndSettle();
+        expect(valueIndicatorBox, paintsExactlyCountTimes(#drawPath, 1));
 
-      // Tap on the 75% position of the Slider
-      await tester.tapAt(tapPositionRight);
-      await tester.pumpAndSettle();
-      expect(valueIndicatorBox, paintsExactlyCountTimes(#drawPath, 0));
+        // Tap on the 75% position of the Slider
+        await tester.tapAt(tapPositionRight);
+        await tester.pumpAndSettle();
+        expect(valueIndicatorBox, paintsExactlyCountTimes(#drawPath, 0));
+      }
     } finally {
       debugDisableShadows = true;
     }
@@ -2751,22 +2759,27 @@ Widget _buildRangeApp(
     ),
   );
 }
-Widget _buildSilderApp() {
+Widget _buildSilderApp(SliderComponentShape sliderComponentShape) {
   double sliderValue = 10;
   return MaterialApp(
     home: StatefulBuilder(
       builder: (BuildContext context, void Function(void Function()) setState) {
         return Material(
-          child: Slider(
-            value: sliderValue,
-            max: 100,
-            label: sliderValue > 50 ? null : sliderValue.toString(),
-            divisions: 10,
-            onChanged: (double value) {
-              setState(() {
-                sliderValue = value;
-              });
-            },
+          child: SliderTheme(
+            data: SliderTheme.of(context).copyWith(
+              valueIndicatorShape: sliderComponentShape,
+            ),
+            child: Slider(
+              value: sliderValue,
+              max: 100,
+              label: sliderValue > 50 ? null : sliderValue.toString(),
+              divisions: 10,
+              onChanged: (double value) {
+                setState(() {
+                  sliderValue = value;
+                });
+              },
+            ),
           ),
         );
       },