pinch_zoom_any

Add pinch-to-zoom, pan, double-tap to zoom, and double-tap to reset to any Flutter widget — with zero external dependencies.

Features

🤏 Pinch to zoom — smooth, natural gesture using Flutter's scale gesture
✋ Pan / drag while zoomed — move freely around the zoomed content
👆 Double-tap to zoom — toggles between 1× and doubleTapScale
🔄 Double-tap to reset — if already zoomed, double-tap returns to 1×
⚡ resetOnRelease — snap back to original size when fingers lift
📡 onScaleChanged callback — react to scale changes in real time
🎨 Works on any widget — images, cards, text, custom widgets, anything

Getting started

Add to your pubspec.yaml:

dependencies:
  pinch_zoom_any: ^0.1.0

Then run:

flutter pub get

Usage

import 'package:pinch_zoom_any/pinch_zoom_any.dart';

PinchZoomAny(
  child: Image.network('https://example.com/photo.jpg'),
)

With custom zoom limits

PinchZoomAny(
  minScale: 1.0,
  maxScale: 5.0,
  doubleTapScale: 2.5,
  child: Image.asset('assets/map.png'),
)

Reset on release (e.g. for previews)

PinchZoomAny(
  resetOnRelease: true,
  child: Card(
    child: Padding(
      padding: EdgeInsets.all(16),
      child: Text('Pinch me — I snap back!'),
    ),
  ),
)

React to scale changes

PinchZoomAny(
  onScaleChanged: (scale) {
    print('Current scale: $scale');
  },
  child: MyCustomWidget(),
)

API Reference

`PinchZoomAny`

Parameter	Type	Default	Description
`child`	`Widget`	required	The widget to make zoomable
`minScale`	`double`	`1.0`	Minimum zoom level
`maxScale`	`double`	`4.0`	Maximum zoom level
`doubleTapScale`	`double`	`2.0`	Zoom level reached on double-tap
`resetOnRelease`	`bool`	`false`	Snap back to 1× when fingers lift
`clipBehavior`	`Clip`	`Clip.hardEdge`	Clipping applied to zoomed content
`onScaleChanged`	`ValueChanged<double>?`	`null`	Callback fired on every scale change

How it works

PinchZoomAny uses Flutter's built-in GestureDetector with onScaleStart, onScaleUpdate, and onScaleEnd to track the pinch gesture. A Matrix4 transform is applied via Transform to scale and translate the child. An AnimationController handles smooth snap-back and double-tap transitions.

No external packages are used — this is pure Flutter.

License

MIT — see LICENSE.