java图形未显示在JFrame上
我不熟悉java中的图形,由于某些原因,图形没有显示在jframe上。我对如何设置和实例化图形感到困惑。代码中也可能有一个愚蠢的错误,我只是没有看到。谢谢你的反馈
地图类
public class Map extends JPanel{
private static int WIDTH;
private static int HEIGHT;
private static int ROWS;
private static int COLS;
private static int TILE_SIZE;
private static int CLEAR = 0;
private static int BLOCKED = 1;
private static int[][] GRID;
public Map(int w, int h, int t){
WIDTH = w;
HEIGHT = h;
TILE_SIZE = t;
ROWS = HEIGHT/TILE_SIZE;
COLS = WIDTH/TILE_SIZE;
GRID = new int[ROWS][COLS];
for (int row = 0; row < ROWS; row++){
for (int col = 0; col < COLS; col++){
GRID[row][col] = BLOCKED;
}
}
randomMap();
}
public void randomMap(){
int row = 0;
int col = 0;
int turn;
Random rand = new Random();
GRID[row][col] = CLEAR;
do{
turn = rand.nextInt(2)+1;
if (turn == 1)
row++;
else
col++;
GRID[row][col] = CLEAR;
}while(row<ROWS-1 && col<COLS-1);
if (row == ROWS-1){
for (int i = col; i < COLS; i++){
GRID[row][i] = CLEAR;
}
}
else{
for (int i = row; i < ROWS; i++){
GRID[i][col] = CLEAR;
}
}
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
for (int row = 0; row < WIDTH; row++){
for (int col = 0; col < HEIGHT; col++){
if (GRID[row][col] == 1){
g2d.setColor(Color.BLACK);
g2d.fillRect(row*TILE_SIZE, col*TILE_SIZE, TILE_SIZE, TILE_SIZE);
}else{
g2d.setColor(Color.WHITE);
g2d.fillRect(row*TILE_SIZE, col*TILE_SIZE, TILE_SIZE, TILE_SIZE);
}
}
}
}
public void displayConsole(){
for (int row = 0; row < ROWS; row++){
for (int col = 0; col < COLS; col++){
System.out.print(GRID[row][col] + " ");
}
System.out.println("");
System.out.println("");
}
}
}
游戏课
public class Game extends JFrame{
private Map map;
public Game(){
setLayout(null);
setBounds(0,0,500,500);
setSize(500,500);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Map map = new Map(500,500,50);
map.displayConsole();
add(map);
repaint();
setVisible(true);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Game game = new Game();
}
}
# 1 楼答案
涂漆部件的尺寸可能为0x0。自定义绘制的组件应返回组件的首选尺寸
将构件添加到框架后,打包框架,以确保框架的大小与显示构件所需的大小完全一致
当然,在框架中使用或设置适当的布局/约束。在本例中,我将使用默认布局
BorderLayout
和默认约束CENTER
# 2 楼答案
安德鲁是对的。我不得不重新布置才能让它工作。我添加了
perferredSize()
和minimumSize()
的代码,并添加了对pack()
的调用,删除了setLayout(null)
。此外,计算高度和宽度时也会遇到问题,它们不会与行和列对齐,并且会将索引抛出边界更正了下面的代码