当我调用postInvalidate（）时为什么OnDraw没有触发？

Question

我试图在Activitie的布局上绘制GridView，但没有触发public class StrangeCalculation { public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println("What is the first number?"); int num1 = input.nextInt(); System.out.println("What is the second number?"); int num2 = input.nextInt(); int min = Math.min(num1, num2); int max = Math.max(num1, num2); int sum = min + max; int diff = max - min; // Main logic double strangeValue = (Math.pow(10, (sum + "").length()) * diff + sum); } } 方法。什么可能是错的？

自定义视图类

onDraw()

我打电话给画的地方。

package com.example.twinkle94.lab_work;

import android.content.Context;
import android.graphics.Canvas;
import android.support.annotation.Nullable;
import android.support.v4.content.ContextCompat;
import android.util.AttributeSet;
import android.widget.GridView;

public class GameView extends GridView
{
    private int background_color;
    private int player_color;
    private int wall_color;

    private int[][] game_field;

    private GameViewAdapter adapter;

    public GameView(Context context)
    {
        super(context);

        setWillNotDraw(false);
    }

    public GameView(Context context, @Nullable AttributeSet attrs)
    {
        super(context, attrs);

        setWillNotDraw(false);

        background_color = ContextCompat.getColor(context, R.color.background_color);
        player_color = ContextCompat.getColor(context, R.color.player_color);
        wall_color = ContextCompat.getColor(context, R.color.wall_color);

        game_field = new int[3][3];

        adapter = new GameViewAdapter(context);
        this.setAdapter(adapter);

        //TODO: change to dynamic!
        setNumColumns(3);

        //TODO: change to dynamic!
        game_field[0][0] = player_color;
        game_field[0][1] = player_color;
        game_field[0][2] = wall_color;
        game_field[1][0] = background_color;
        game_field[1][1] = wall_color;
        game_field[1][2] = player_color;
        game_field[2][0] = wall_color;
        game_field[2][1] = background_color;
        game_field[2][2] = player_color;
    }

    public GameView(Context context, @Nullable AttributeSet attrs, int defStyleAttr)
    {
        super(context, attrs, defStyleAttr);

        setWillNotDraw(false);
    }

    public void onUpdate()
    {

    }

    @Override
    protected void onDraw(Canvas canvas)
    {
        super.onDraw(canvas);

        for(int i = 0; i < game_field.length; i++)
        {
            for(int j = 0; j < game_field[i].length; j++)
            {
                adapter.add(game_field[i][j]);
                adapter.update();
            }
        }
    }

    public void draw()
    {
        postInvalidate();
    }
}

活动类

package com.example.twinkle94.lab_work;


import android.content.Context;

public class Game
{
    private Context context;
    private GameView gameView;

    public Game(Context context)
    {
        this.context = context;
        gameView = (GameView) ((MainActivity)context).findViewById(R.id.gameView);
    }

    public void run()
    {
        while(true)
        {
            gameView.draw();

            try
            {
                Thread.sleep(1000);
            }
            catch (InterruptedException e)
            {
                e.printStackTrace();
            }
        }
    }
}

布局，当然

package com.example.twinkle94.lab_work;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity
{

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        new Game(this).run();
    }


}

感谢您的帮助，谢谢！

Answer 1

我已经解决了。问题是无限循环。它阻止了UI线程显示视图。