public static void main(String[] args) {
Picture myPic = new Picture(600, 600);
Graphics canvas = myPic.getOffScreenGraphics();
canvas.setColor(Color.WHITE);
canvas.fillRect(0, 0, 600, 600);
canvas.setColor(Color.BLACK);
int x1;
int y1;
int x2;
int y2;
int heading;
x1 = 300;
y1 = 300;
x2 = 300;
y2 = 300;
heading = 0;
String keyboard = JOptionPane.showInputDialog(null,
"Enter your input");
if (keyboard != null) {
if (keyboard.isEmpty() || keyboard.contains(" ")) {
JOptionPane.showMessageDialog(
null,
"Please enter an input",
"Error",
JOptionPane.ERROR_MESSAGE);
main(args);
}
int counth = 0;
int countg = 0;
int countPlus = 0;
int countMinus = 0;
int countK = 0;
int countR = 0;
int countG = 0;
int countB = 0;
int countC = 0;
int countO = 0;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == '+') {
if (heading == 0) {
heading = 1;
} else if (heading == 1) {
heading = 2;
} else if (heading == 2) {
heading = 3;
} else if (heading == 3) {
heading = 0;
}
}
}
countPlus++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == '-') {
if (heading == 0) {
heading = 3;
} else if (heading == 1) {
heading = 0;
} else if (heading == 2) {
heading = 1;
} else if (heading == 3) {
heading = 2;
}
}
}
countMinus++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'h' || keyboard.charAt(i) == 'f') {
if (heading == 0) {
counth++;
int k = 10 * (counth);
canvas.drawLine(x1, y1, x2, y2 + k);
} else if (heading == 1) {
counth++;
int k = 10 * (counth);
canvas.drawLine(x1, y1, x2 + k, y2);
} else if (heading == 2) {
counth++;
int k = 10 * (counth);
canvas.drawLine(x1, y1, x2, y2 - k);
} else if (heading == 3) {
counth++;
int k = 10 * (counth);
canvas.drawLine(x1, y1, x2 - k, y2);
} else if (heading > 3 || heading < 0) {
JOptionPane.showMessageDialog(
null,
"Your heading is greater than 3 or less than 0",
"Error",
JOptionPane.ERROR_MESSAGE);
main(args);
}
}
}
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'K') {
canvas.setColor(Color.BLACK);
}
}
countK++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'R') {
canvas.setColor(Color.RED);
}
}
countR++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'G') {
canvas.setColor(Color.GREEN);
}
}
countG++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'B') {
canvas.setColor(Color.BLUE);
}
}
countB++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'C') {
canvas.setColor(Color.CYAN);
}
}
countC++;
for (int i = 0; i < keyboard.length(); i++) {
if (keyboard.charAt(i) == 'O') {
canvas.setColor(Color.BLACK);
}
}
countO++;
System.out.println("h = " + counth);
System.out.println("g = " + countg);
System.out.println("+ = " + countPlus);
System.out.println("- = " + countMinus);
System.out.println("K = " + countK);
System.out.println("R = " + countR);
System.out.println("G = " + countG);
System.out.println("B = " + countB);
System.out.println("C = " + countC);
System.out.println("O = " + countO);
myPic.repaint();
} else {
System.exit(0);
}
}
我正在尝试根据用户输入绘制一些线条。
输入是 h 和 f 用于向前移动 10 个像素(两者都做同样的事情)和 + 或 - 来改变线将移动 90 度的方向,无论是顺时针移动 90 度,还是逆时针移动 -(默认是向上移动)。
例如,如果用户输入:“hhh”,则该行将向上移动 30 个像素。
我遇到的问题是我希望用户能够输入 hhh+hhh 并向上绘制 30 个像素的线,然后转向并在右侧绘制 30 个像素。然而,在我的程序中,当我输入 hhh+hhh 时,它只会使一条直线向右 60 像素。
所以我的问题是:当它在指定方向看到 + 或 - 并画另一条线时,我怎样才能让它画一条线。