NCURSES

Question

我正在用 ncurses 编写应用程序，但无法在 Pad 中移动光标。有办法吗？我认为 wmove(Window w, int y, int x) 应该是正确的方法，但我无法那样做...我做错了什么吗？

int main(void)
{
    WINDOW *p;
    FILE *f;
    int ch;
    initscr();
    keypad(stdscr, TRUE);
    /* create a new pad */
    p = newpad(WIDE,COLS);
    if( p == NULL )
    bomb("Unable to create new pad\n");
    /* open the file */
    f = fopen(FILENAME,"r");
    if( f == NULL)
    bomb("Unable to open file\n");
    int i =0;
    while( (ch=fgetc(f)) != EOF){
        waddch(p,ch);
    }
    fclose(f);
    prefresh(p,0, 0, 0,0, LINES-1,COLS-1);
    int c, cursorY=0, cursorX=0, linseCount = 0;
    wmove(p,2,2);
    while((c=wgetch(p))!='q'){
        switch(c){
          case KEY_LEFT:
                if(cursorX != 0)
                    cursorX--;
                break;
         case KEY_RIGHT:
                if (cursorX != COLS-1)
                    cursorX++;
                break;
         case KEY_UP:
                if(cursorY==0  && linseCount==0)
                    break;
                else if(cursorY == 0){
                    linseCount--;
                    prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);
                }
                else
                    cursorY--;
                break;
         case KEY_DOWN:
                if(cursorY==LINES-1  && linseCount==WIDE-1)
                    break;
                else if(cursorY == LINES-1){
                    linseCount++;
                    prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);
                }
                else
                    cursorY--;
                break;  
        }
        wmove(p,cursorY,cursorX);
        prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1); 

    }
    endwin();
return 0;
}

|||-------------------- 编辑 - 解决方案---------------- ------|||

int main(void)
 {
    WINDOW *p;
    FILE *f;
    int ch;
    initscr();
    savetty();
    noecho();//disable auto-echoing
    cbreak();//making getch() work without a buffer I.E. raw characters
    keypad(stdscr,TRUE);//allows use of special keys, namely the arrow keys
    clear();    // empty the screen
    timeout(0); 

    /* create a new pad */
    p = newpad(WIDE,COLS);
    keypad(p, TRUE);
    if( p == NULL )
        bomb("Unable to create new pad\n");

    /* open the file */
    f = fopen(FILENAME,"r");
    if( f == NULL)
    bomb("Unable to open file\n");
    /* display file’s contents on the pad */

    while( (ch=fgetc(f)) != EOF)
        waddch(p,ch);
    fclose(f);


    /* display the pad’s contents on the screen */
    prefresh(p,0, 0, 0,0, LINES-1,COLS-1);
    int c, cursorY=0, cursorX=0, linseCount = 0;
    while((c=wgetch(p))!='q'){
        switch(c){
           case KEY_LEFT:
                    if(cursorX != 0)
                        cursorX--;
                    break;
            case KEY_RIGHT:
                    if (cursorX != COLS-1)
                        cursorX++;
                    break;
            case KEY_UP:
                    if(cursorY==0  && linseCount==0)
                        break;
                    else if(cursorY == linseCount){
                        cursorY--;
                        linseCount--;
                        prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);
                    }
                    else
                        cursorY--;
                    break;
            case KEY_DOWN:
                    if(cursorY==LINES-1  && linseCount==WIDE-1)
                        break;
                    else if(cursorY == linseCount+LINES-1){
                        cursorY++;
                        linseCount++;
                        prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);
                    }
                    else
                        cursorY++;
                    break;  
            }
            wmove(p,cursorY,cursorX);
            prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);
    }
    endwin();
    return 0;
}

Answer 1

这两行导致光标所在的位置与变量 curserX 和 curserY 认为光标所在的位置不同。

int c, cursorY=0, cursorX=0, linseCount = 0;
wmove(p,2,2);

这段代码，在处理一个key_down方向键

if(cursorY==LINES-1  && linseCount==WIDE-1)

正在根据不正确的 x 宽度检查 'linsecount'。

建议开始诅咒：

initscr();
savetty();
noecho();//disable auto-echoing
cbreak();//making getch() work without a buffer I.E. raw characters
keypad(stdscr,TRUE);//allows use of special keys, namely the arrow keys
clear();    // empty the screen
timeout(0); // reads do not block

当处理 key_down 箭头键时，有这一行：

else if(cursorY == LINES-1){

导致光标没有动作的结果不在底线

建议：

else if(cursorY < LINES-1){

其他键处理函数需要类似的更正

来自许多 ncurses 和 pad 函数的 returned 代码需要检查。对这些 return 代码进行错误检查将使失败的原因一目了然。

使用此程序时：

prefresh(p,linseCount, 0, 0,0, LINES-1,COLS-1);

强烈建议，在调试问题之前，刷新整个 pad 而不是仅刷新一行

Answer 2

在 p = newpad(WIDE,COLS); 添加此调用后添加以下调用：

keypad(p, TRUE);

这将使您的键盘能够正确处理箭头键产生的转义序列...

NCURSES - 在 pad 中移动光标

NCURSES - Moving cursor in pad

c