在窗口中移动光标 - ncurses

Question

我用ncurse创建了一个窗口，我试图用我的窗口内的箭头键移动光标，并且只能在里面移动光标。对于我的理解我必须使用wmove()，但显然我没有得到如何使用它。

下面是一些代码片段，让你知道我做了什么：

int main(int argc, char **argv) 
{ 
    WINDOW *my_win; 
    int startx, starty, width, height; 
    int ch; 
    int x = 50; 
    int y = 5; 

    initscr(); 
    cbreak(); 
    keypad(stdscr, TRUE); 
    noecho(); 

    height = 10; 
    width = 100; 
    starty = (LINES - height)/2; 
    startx = (COLS - width)/2; 
    printw("Press F1 to exit"); 
    refresh(); 
    my_win = create_newwin(25, 50, y, x); 
    wmove(my_win, y, x); 

    while((ch = getch()) != KEY_F(1)) 
    { 
     if ((ch = getch()) == KEY_RIGHT) 
     wmove(my_win, y++, x++); 
     refresh(); 
    } 

    endwin(); 
    return 0; 
} 

WINDOW *create_newwin(int height, int width, int starty, int startx) 
{ 
    WINDOW *local_win; 

    local_win = newwin(height, width, starty, startx); 
    box(local_win, 0, 0); 
    wrefresh(local_win); 

    return (local_win); 
} 

Answer 1

我只是有一点你的代码。

我觉得主要的问题是你做了refresh()整个屏幕，当刷新窗口wrefresh (my_win)本来就够了。

问题二：你是等待keystrke两次： 1. while循环 2. if声明。

getch()在while循环中就足够了。我们可以在循环中使用ch来检测按下了哪个键。

我会做一个switch代替if选择：

while((ch = getch()) != 'q') 
    { 
     switch (ch) 
     { 
      case KEY_LEFT: 
      x--; 
      break; 
      case KEY_RIGHT: 
      x++; 
      break; 
      case KEY_UP: 
      y--; 
      break; 
      case KEY_DOWN: 
      y++; 
      break; 
     } 

     wmove(my_win, y, x); 
     wrefresh(my_win); 
    } 

我也去掉了一些unnessacery声明。

这里是我做了什么：

#include <stdio.h> 
#include <ncurses.h> 

WINDOW *create_newwin(int height, int width, int starty, int startx) 
{ 
    WINDOW *local_win = newwin(height, width, starty, startx); 
    box(local_win, 0, 0); 
    wrefresh(local_win); 

    return (local_win); 
} 

int main(int argc, char **argv) 
{ 
    WINDOW *my_win; 

    int ch; 
    int x = 2; 
    int y = 2; 

    initscr(); 
    cbreak(); 
    keypad(stdscr, TRUE); 
    noecho(); 

    printw("Press q to exit"); 
    refresh(); 
    my_win = create_newwin(10, 20, y, x); 
    wmove(my_win, y, x); 
    wrefresh(my_win); 

    while((ch = getch()) != 'q') 
    { 
     switch (ch) 
     { 
      case KEY_LEFT: 
      x--; 
      break; 
      case KEY_RIGHT: 
      x++; 
      break; 
      case KEY_UP: 
      y--; 
      break; 
      case KEY_DOWN: 
      y++; 
      break; 
     } 

     wmove(my_win, y, x); 
     wrefresh(my_win); 
    } 

    endwin(); 
    return 0; 
} 

如果x或y获得比窗口大小大或变小，光标不移动，但数值仍然量变到质变。因此，当数值在窗口大小内时，请确保只允许减少或增加x和y！

提示：

case KEY_LEFT: 
    if (x>0) { x--; } 
    break; 

Answer 2

其实，一个更好的解决办法是使用wgetch为my_win窗口，并消除大多数的调用来refresh和wrefresh。 wgetch（getch）在正在读取的窗口上进行刷新。到Zehetner的例子中的变化会是这样的：

--- foo3.c.orig 2015-04-02 19:53:18.000000000 -0400 
+++ foo3.c  2015-04-02 19:56:31.000000000 -0400 
@@ -1,11 +1,12 @@ 
#include <stdio.h> 
#include <ncurses.h> 

+static 
WINDOW *create_newwin(int height, int width, int starty, int startx) 
{ 
    WINDOW *local_win = newwin(height, width, starty, startx); 
    box(local_win, 0, 0); 
- wrefresh(local_win); 
+ keypad(local_win, TRUE); 

    return (local_win); 
} 
@@ -27,9 +28,8 @@ 
    refresh(); 
    my_win = create_newwin(10, 20, y, x); 
    wmove(my_win, y, x); 
- wrefresh(my_win); 

- while((ch = getch()) != 'q') 
+ while((ch = wgetch(my_win)) != 'q') 
    { 
     switch (ch) 
     { 
@@ -45,10 +45,12 @@ 
      case KEY_DOWN: 
      y++; 
      break; 
+   default: 
+   beep(); 
+   break; 
     } 

     wmove(my_win, y, x); 
-  wrefresh(my_win); 
    } 

    endwin(); 

或（导致程序）：

#include <stdio.h> 
#include <ncurses.h> 

static 
WINDOW *create_newwin(int height, int width, int starty, int startx) 
{ 
    WINDOW *local_win = newwin(height, width, starty, startx); 
    box(local_win, 0, 0); 
    keypad(local_win, TRUE); 

    return (local_win); 
} 

int main(int argc, char **argv) 
{ 
    WINDOW *my_win; 

    int ch; 
    int x = 2; 
    int y = 2; 

    initscr(); 
    cbreak(); 
    keypad(stdscr, TRUE); 
    noecho(); 

    printw("Press q to exit"); 
    refresh(); 
    my_win = create_newwin(10, 20, y, x); 
    wmove(my_win, y, x); 

    while((ch = wgetch(my_win)) != 'q') 
    { 
     switch (ch) 
     { 
      case KEY_LEFT: 
      x--; 
      break; 
      case KEY_RIGHT: 
      x++; 
      break; 
      case KEY_UP: 
      y--; 
      break; 
      case KEY_DOWN: 
      y++; 
      break; 
      default: 
      beep(); 
      break; 
     } 

     wmove(my_win, y, x); 
    } 

    endwin(); 
    return 0; 
}