8x8井字棋对角线检测问题：无法识别中间区域连续匹配

我正在对至少5x5的矩阵（示例为8x8）做对角线检测，需要遍历多行对应的新列，用来记录玩家点击按钮后的颜色选择。目前现有代码能正常遍历边缘区域，但无法触发中间区域的对角线连续匹配记录。

正常处理边缘的代码 #

JButton[][] buttons = new JButton[8][8];
String red = "";
String green = "";
String blue = "";
int col = 0;
        for (int row = 0; row < 8; row++, col++) {
            if (buttons[row][col].getBackground() == Color.RED) {
                red = red.concat("+");
            } else if (buttons[row][col].getBackground() == Color.GREEN) {
                green = green.concat("+");
            } else if (buttons[row][col].getBackground() == Color.BLUE) {
                blue = blue.concat("+");
            } else {
                red = red.concat(",");
                green = green.concat(",");
                blue = blue.concat(",");
            }
        }

尝试修复问题的代码 #

JButton[][] buttons = new JButton[8][8];
String red = "";
String green = "";
String blue = "";
int col = 0;
for (int loop = 0; loop < 5; loop++) {
        for (int row = (0 + loop); row < 8; row++, col++) {
            if (buttons[row][col].getBackground() == Color.RED) {
                red = red.concat("+");
            } else if (buttons[row][col].getBackground() == Color.GREEN) {
                green = green.concat("+");
            } else if (buttons[row][col].getBackground() == Color.BLUE) {
                blue = blue.concat("+");
            } else {
                red = red.concat(",");
                green = green.concat(",");
                blue = blue.concat(",");
            }
        }
}

内容的提问来源于stack exchange，提问作者Valentine