java - 西蒙说按下按钮后按钮颜色不会恢复正常

Question

public void flashButton(int color) {
    final ImageView colors = findViewById(R.id.buttonsImage);
    final int newColor = color;

    Handler handler = new Handler();
    final Runnable r = new Runnable() {
        public void run() {
            if(newColor == 1)
                colors.setImageResource(R.drawable.green_activated_png);
            if(newColor == 2)
                colors.setImageResource(R.drawable.yellow_activated_png);
            if(newColor == 3)
                colors.setImageResource(R.drawable.red_activated_png);
            if(newColor == 4)
                colors.setImageResource(R.drawable.blue_activated_png);

            System.out.println("Flashed color: " + newColor);
        }
    };
    handler.postDelayed(r, 1000);

    colors.setImageResource(R.drawable.normal_buttons);
    System.out.println("Returned Color.");
}

使用 R.drawable.green_activated_png 为每个按钮更改按钮颜色)。然后，我将其改回 (R.drawable.normal_buttons)。我认为我的问题出在 handler.postDelayed(r, 1000) 中。但是在用户按下正确的颜色后，颜色不会变回正常。

Answer 1

你的做法正好相反。你必须在按下 Button 后立即更改它的颜色，并且你必须将返回的颜色保留在 postDelayed 中以便在给定时间延迟后变为正常颜色。

public void flashButton(int color) {
    final ImageView colors = findViewById(R.id.buttonsImage);
    final int newColor = color;
    if(newColor == 1)
        colors.setImageResource(R.drawable.green_activated_png);
    if(newColor == 2)
        colors.setImageResource(R.drawable.yellow_activated_png);
    if(newColor == 3)
        colors.setImageResource(R.drawable.red_activated_png);
    if(newColor == 4)
        colors.setImageResource(R.drawable.blue_activated_png);
    System.out.println("Flashed color: " + newColor);

    Handler handler = new Handler();
    final Runnable r = new Runnable() {
        public void run() {
            colors.setImageResource(R.drawable.normal_buttons);
            System.out.println("Returned Color.");
        }
    };
    handler.postDelayed(r, 1000);
}