AnimatedBuilderが効かない【Flutter】

Question

正常に動作するContainerをAnimatedBuilderで囲うと非表示になってしまいます。
-(アニメーションのあるRaisedButtonを表示させる予定)
-エラーはないです。

解決策を教えて頂けると嬉しいです。

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(　　　　　　　　　　　　　　　<------------------AnimatedBuilderで囲うと、Containerが表示されない????
      animation: _scaleAnimationController,
      builder: (context, child) => Transform.scale(
        scale: _scaleAnimation.value,
      ),
      child: Container(                               <------------------Containerのみだと正常に表示
        margin: EdgeInsets.only(bottom: 20),
        child: Center(
          child: RaisedButton(
            onPressed: () {
              _scaleAnimationController.forward();
            },
            padding: EdgeInsets.zero,
            color: widget.primaryColor,
            splashColor: widget.primaryColor,
            highlightColor: widget.primaryColor,
            child: Container(
              width: 200,
              height: 50,
              child: Row(
                children: [
                  Expanded(
                    flex: 3,
                    child: Center(
                      child: Text(
                        'Download',
                        style: TextStyle(color: Colors.white, fontSize: 16),
                      ),
                    ),
                  ),
                  Expanded(
                    flex: 1,
                    child: Container(
                      decoration: BoxDecoration(
                          color: widget.darkPrimaryColor,
                          borderRadius: BorderRadius.only(
                            bottomRight: Radius.circular(4),
                            topRight: Radius.circular(4),
                          )),
                      child: Center(
                          child: Icon(
                        Icons.arrow_downward,
                        color: Colors.white,
                      )),
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

---

????以下、home.dart, ButtonAnimation.dartの全文を掲載します。
ご検証にお使いくださいませ。

-home.dartからButtonAnimationクラスを呼んでいます。

import 'package:flutter/material.dart';
import 'ButtonAnimation.dart';

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          ButtonAnimation(
            primaryColor: Colors.indigo,
            darkPrimaryColor: Colors.indigo[900],
          ),
          ButtonAnimation(
            primaryColor: Colors.orange,
            darkPrimaryColor: Colors.orange[900],
          ),
          ButtonAnimation(
            primaryColor: Colors.green,
            darkPrimaryColor: Colors.green[900],
          ),
          ButtonAnimation(
            primaryColor: Colors.red,
            darkPrimaryColor: Colors.red[900],
          ),
        ],
      ),
    );
  }
}

import 'package:flutter/material.dart';

class ButtonAnimation extends StatefulWidget {
  final Color primaryColor;
  final Color darkPrimaryColor;

  const ButtonAnimation({Key key, this.primaryColor, this.darkPrimaryColor})
      : super(key: key);

  @override
  _ButtonAnimationState createState() => _ButtonAnimationState();
}

class _ButtonAnimationState extends State<ButtonAnimation>
    with TickerProviderStateMixin {
  AnimationController _animationController;
  AnimationController _scaleAnimationController;
  AnimationController _fadeAnimationController;

  Animation<double> _animation;
  Animation<double> _scaleAnimation;
  Animation<double> _fadeAnimation;

  double buttonWidth = 200;
  double scale = 1.0;
  double barColorOpacity = 0.6;
  bool animationComplete = false;
  bool animationStart = false;

  @override
  void initState() {
    _animationController =
        AnimationController(vsync: this, duration: Duration(seconds: 3));
    _scaleAnimationController =
        AnimationController(vsync: this, duration: Duration(milliseconds: 300));
    _fadeAnimationController =
        AnimationController(vsync: this, duration: Duration(milliseconds: 400));

    _animation = Tween<double>(begin: 0, end: buttonWidth)
        .animate(_animationController)
          ..addStatusListener((status) {});

    _scaleAnimation = Tween<double>(begin: 1, end: 1.5)
        .animate(_fadeAnimationController)
          ..addStatusListener((status) {});

    _fadeAnimation =
        Tween<double>(begin: 50, end: 0).animate(_fadeAnimationController);

    super.initState();
  }

  @override
  void dispose() {
    _animationController.dispose();
    _scaleAnimationController.dispose();
    _fadeAnimationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _scaleAnimationController,
      builder: (context, child) => Transform.scale(
        scale: _scaleAnimation.value,
      ),
      child: Container(
        margin: EdgeInsets.only(bottom: 20),
        child: Center(
          child: RaisedButton(
            onPressed: () {
              _scaleAnimationController.forward();
            },
            padding: EdgeInsets.zero,
            color: widget.primaryColor,
            splashColor: widget.primaryColor,
            highlightColor: widget.primaryColor,
            child: Container(
              width: 200,
              height: 50,
              child: Row(
                children: [
                  Expanded(
                    flex: 3,
                    child: Center(
                      child: Text(
                        'Download',
                        style: TextStyle(color: Colors.white, fontSize: 16),
                      ),
                    ),
                  ),
                  Expanded(
                    flex: 1,
                    child: Container(
                      decoration: BoxDecoration(
                          color: widget.darkPrimaryColor,
                          borderRadius: BorderRadius.only(
                            bottomRight: Radius.circular(4),
                            topRight: Radius.circular(4),
                          )),
                      child: Center(
                          child: Icon(
                        Icons.arrow_downward,
                        color: Colors.white,
                      )),
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}

Answer 1

アニメーションさせる要素はbuilder関数で作る必要があります。
AnimationBuilder

    return AnimatedBuilder(
        animation: _scaleAnimationController,
        builder: (context, child) {
          return Transform.scale(
            scale: _scaleAnimation.value,
            child: Container(
              margin: EdgeInsets.only(bottom: 20),
              child: Center(
                  .
                  .

ちなみに、この部分の_fadeAnimationControllerは_scaleAnimationControllerの間違いでしょうか？

    _scaleAnimation = Tween<double>(begin: 1, end: 1.5)
        .animate(_fadeAnimationController)
          ..addStatusListener((status) {});

Comments

[kazuki_user]

丁寧な返信ありがとうございます????

非表示の原因は、Transform.scale()のカッコ内にchild: Container~が
含まれていなかった事でした..????

parentの値を間違えていました????ご指摘ありがとうございます。