Flutter 更新文本小部件

Question

I am new with Flutter and I face a problem, I followed this flappy bird tutorial made in Dart I am trying to update a Text widget with a score integer and I am incrementing score each time a barrier passes by, the barriers moves in startGame and it updates score in startGame but it doesn't update Text.

How do I make it so Text gets updated accordingly?

Code:

import 'dart:async';

import 'package:flappy_bird_project/barriers.dart';
import 'package:flappy_bird_project/bird.dart';
import 'package:flutter/material.dart';

class HomePage extends StatefulWidget {
  @override
  _HomepageState createState() => _HomepageState();
}

class _HomepageState extends State<HomePage> {
  static double birdYaxis = 0;
  double time = 0;
  double height = 0;
  double initialHeight = birdYaxis;
  bool gameHasStarted = false;

  static double barrierXone = 1;
  double barrierXtwo = barrierXone + 1.5;
  int score = 0;
  int highscore = 10;

  void jump() {
    setState(() {
      time = 0;
      initialHeight = birdYaxis;
    });
  }

  void startGame() {
    gameHasStarted = true;
    Timer.periodic(Duration(milliseconds: 60), (timer) {
      time += 0.05;
      height = -4.9 * time * time + 2.8 * time;
      setState(() {
        birdYaxis = initialHeight - height;
      });
      setState(() {
        if (barrierXone < -2) {
          barrierXone += 3.5;
        } else {
          barrierXone -= 0.05;
        }
      });
      setState(() {
        if (barrierXtwo < -2) {
          barrierXtwo += 3.5;
          score++;
        } else {
          barrierXtwo -= 0.05;
        }
      });
      setState(() {
        if (barrierXone == 0 || barrierXtwo == 0) {
          score++;
        }
      });
      if (birdYaxis > 1) {
        timer.cancel();
        gameHasStarted = false;
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {
        if (gameHasStarted) {
          jump();
        } else {
          startGame();
        }
      },
      child: Scaffold(
          body: Column(
        children: [
          Expanded(
            flex: 2,
            child: Stack(
              children: [
                AnimatedContainer(
                  alignment: Alignment(0, birdYaxis),
                  duration: Duration(milliseconds: 0),
                  color: Colors.blue,
                  child: MyBird(),
                ),
                Container(
                  alignment: Alignment(0, -0.3),
                  child: gameHasStarted
                      ? Text(" ")
                      : Text(
                          "T A P  T O  P L A Y",
                          style: TextStyle(fontSize: 20, color: Colors.white),
                        ),
                ),
                AnimatedContainer(
                  alignment: Alignment(barrierXone, 1.1),
                  duration: Duration(milliseconds: 0),
                  child: MyBarrier(
                    size: 200.0,
                  ),
                ),
                AnimatedContainer(
                  alignment: Alignment(barrierXone, -1.1),
                  duration: Duration(milliseconds: 0),
                  child: MyBarrier(
                    size: 200.0,
                  ),
                ),
                AnimatedContainer(
                  alignment: Alignment(barrierXtwo, 1.1),
                  duration: Duration(milliseconds: 0),
                  child: MyBarrier(
                    size: 150.0,
                  ),
                ),
                AnimatedContainer(
                  alignment: Alignment(barrierXtwo, -1.1),
                  duration: Duration(milliseconds: 0),
                  child: MyBarrier(
                    size: 250.0,
                  ),
                )
              ],
            ),
          ),
          Container(
            height: 15,
            color: Colors.green,
          ),
          Expanded(
              child: Container(
            color: Colors.brown,
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Text("SCORE",
                        style: TextStyle(color: Colors.white, fontSize: 35)),
                    SizedBox(
                      height: 20,
                    ),
                    Text(score.toString(),
                        style: TextStyle(color: Colors.white, fontSize: 35)),
                  ],
                ),
                Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Text("BEST",
                        style: TextStyle(color: Colors.white, fontSize: 35)),
                    SizedBox(
                      height: 20,
                    ),
                    Text(highscore.toString(),
                        style: TextStyle(color: Colors.white, fontSize: 35)),
                  ],
                )
              ],
            ),
          ))
        ],
      )),
    );
  }
}

Answer 1

Since your variable is of type int, you need to use ${} , to perform the assignment.

you can assign the value of a variable to a Text, like this:

Text ("${score}");