animated_padding.0.dart 1.74 KB
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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter/material.dart';

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/// Flutter code sample for [AnimatedPadding].
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void main() => runApp(const AnimatedPaddingExampleApp());
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class AnimatedPaddingExampleApp extends StatelessWidget {
  const AnimatedPaddingExampleApp({super.key});
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  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
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        appBar: AppBar(title: const Text('AnimatedPadding Sample')),
        body: const AnimatedPaddingExample(),
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      ),
    );
  }
}

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class AnimatedPaddingExample extends StatefulWidget {
  const AnimatedPaddingExample({super.key});
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  @override
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  State<AnimatedPaddingExample> createState() => _AnimatedPaddingExampleState();
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}

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class _AnimatedPaddingExampleState extends State<AnimatedPaddingExample> {
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  double padValue = 0.0;
  void _updatePadding(double value) {
    setState(() {
      padValue = value;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        AnimatedPadding(
          padding: EdgeInsets.all(padValue),
          duration: const Duration(seconds: 2),
          curve: Curves.easeInOut,
          child: Container(
            width: MediaQuery.of(context).size.width,
            height: MediaQuery.of(context).size.height / 5,
            color: Colors.blue,
          ),
        ),
        Text('Padding: $padValue'),
        ElevatedButton(
            child: const Text('Change padding'),
            onPressed: () {
              _updatePadding(padValue == 0.0 ? 100.0 : 0.0);
            }),
      ],
    );
  }
}