如何在Android Studios中输出2d阵列的椭圆？

Question

我正在制作一个Android工作室应用程序来玩哈希益智游戏。我想以网格形式输出一个二维数组，如果在决斗迭代中有一个0，我想输出一个带有0的椭圆，如果在迭代中它等于1，它将输出一个带有1等的椭圆等。但是当我运行应用程序时，它只在第一个位置输出1个椭圆。

public class boardView extends View {

public int IslandX;
public int IslandY;

private Canvas canvas;

public boardView(Context context) {
    super(context);
}

int gameBoard[][] = {{0, 0, 0, 0, 1}, {0, 2, 0, 0, 2}, {2, 0, 3, 0, 1}, {0, 0, 0, 0, 0}, {0, 0, 2, 0, 2}};
@TargetApi(Build.VERSION_CODES.LOLLIPOP)

public void onDraw(Canvas canvas){
    Paint Blue = new Paint();
    Blue.setStyle(Paint.Style.FILL);
    Blue.setColor(Color.BLUE);
    for (int i = 0; i < 4; i++) {
        for (int R = 0; R < 4; R++) {
            if (gameBoard[i][R] == 1) {
                // if the iteration = 1 then..
                IslandX = i;
                IslandY = R;

            }else if (gameBoard[i][R]==0){
                IslandX = i;
                IslandY = R;

            }else if (gameBoard[i][R]==2){
                IslandX = i;
                IslandY = R;
            }
            canvas.drawOval(IslandX, IslandY, 50, 50, Blue);
            }
        }
    }
}