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LongPressDraggableCard #

A customizable Flutter widget that allows users to drag a card horizontally to increase or decrease a count — perfect for cart quantities, counters, or any use case where a drag gesture adjusts a numeric value.

📽 Demo #

✨ Features #

• 🔁 Horizontal drag gesture for count control
• 📈 Increase or decrease values dynamically
• ✅ Limit value using maxCount
• 🎨 Customizable feedback (fadeContainer) and UI (child)
• ⚡ Lightweight and easy to integrate

📦 Installation #

Add this to your pubspec.yaml:

dependencies:
  flutter_longpressdrag_fluctuation: ^1.0.0

Then run:

flutter pub get

🚀 Usage #

LongPressDraggableCard(
  axis: Axis.horizontal,
  count: quantity,
  maxCount: 50,
  onChanged: (value) {
    setState(() {
      quantity = value;
    });
  },
  fadeContainer: Container(
    height: 200,
    width: 500,
    margin: EdgeInsets.all(12),
    padding: EdgeInsets.all(16),
    child: Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text("", style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
        SizedBox(height: 8),
        Text("", style: TextStyle(fontSize: 14, color: Colors.grey[700])),
        SizedBox(height: 12),
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Text('', style: TextStyle(fontSize: 16)),
            Text('', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold, color: Colors.green)),
          ],
        ),
      ],
    ),
  ),
  child: Container(
    height: 200,
    width: 500,
    margin: EdgeInsets.all(12),
    padding: EdgeInsets.all(16),
    child: Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text("name", style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
        SizedBox(height: 8),
        Text("description", style: TextStyle(fontSize: 14, color: Colors.grey[700])),
        SizedBox(height: 12),
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Text('Qty: $quantity', style: TextStyle(fontSize: 16)),
            Text('\$10', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold, color: Colors.green)),
          ],
        ),
      ],
    ),
  ),
);

🔧 Parameters #

📌 How it Works #

• LongPressDraggableCard listens for long press + horizontal drag.

• Internally, it uses onDragUpdate to check the offset.dx:

  • Positive → increase count
  • Negative → decrease count

• When the drag ends, onDragEnd resets the feedback offset.

🧪 Example Use Cases #

• Shopping cart item quantity control
• Rating widgets with adjustable values
• Custom counters

💡 Tips #

• Always include a transparent fadeContainer to ensure draggable feedback works.
• Use state management (like setState, Provider, etc.) to persist and respond to value changes.

📄 License #

MIT