既然您已经了解了如何获取按键，现在让我们来看看如何从鼠标获取输入。通常，每个用户界面都允许用户通过键盘和鼠标进行交互。
在您进行任何其他操作之前，您想要接收的事件必须通过以下函数启用：mousemask().
mousemask( mmask_t newmask, /* The events you want to listen to */
mmask_t *oldmask) /* The old events mask */ |
上述函数的第一个参数是一个位掩码，用于指定您想要监听的事件。默认情况下，所有事件都是关闭的。位掩码ALL_MOUSE_EVENTS可以用于获取所有事件。
以下是所有事件掩码
Name Description
---------------------------------------------------------------------
BUTTON1_PRESSED mouse button 1 down
BUTTON1_RELEASED mouse button 1 up
BUTTON1_CLICKED mouse button 1 clicked
BUTTON1_DOUBLE_CLICKED mouse button 1 double clicked
BUTTON1_TRIPLE_CLICKED mouse button 1 triple clicked
BUTTON2_PRESSED mouse button 2 down
BUTTON2_RELEASED mouse button 2 up
BUTTON2_CLICKED mouse button 2 clicked
BUTTON2_DOUBLE_CLICKED mouse button 2 double clicked
BUTTON2_TRIPLE_CLICKED mouse button 2 triple clicked
BUTTON3_PRESSED mouse button 3 down
BUTTON3_RELEASED mouse button 3 up
BUTTON3_CLICKED mouse button 3 clicked
BUTTON3_DOUBLE_CLICKED mouse button 3 double clicked
BUTTON3_TRIPLE_CLICKED mouse button 3 triple clicked
BUTTON4_PRESSED mouse button 4 down
BUTTON4_RELEASED mouse button 4 up
BUTTON4_CLICKED mouse button 4 clicked
BUTTON4_DOUBLE_CLICKED mouse button 4 double clicked
BUTTON4_TRIPLE_CLICKED mouse button 4 triple clicked
BUTTON_SHIFT shift was down during button state change
BUTTON_CTRL control was down during button state change
BUTTON_ALT alt was down during button state change
ALL_MOUSE_EVENTS report all button state changes
REPORT_MOUSE_POSITION report mouse movement |
一旦启用了一类鼠标事件，getch() 类函数每次发生鼠标事件时都会返回 KEY_MOUSE。然后可以使用以下函数检索鼠标事件：getmouse().
代码大致如下所示
MEVENT event;
ch = getch();
if(ch == KEY_MOUSE)
if(getmouse(&event) == OK)
. /* Do some thing with the event */
.
. |
getmouse() 函数将事件返回到传递给它的指针中。它是一个包含以下内容的结构体：
typedef struct
{
short id; /* ID to distinguish multiple devices */
int x, y, z; /* event coordinates */
mmask_t bstate; /* button state bits */
} |
其中的bstate是我们主要关注的变量。它指示鼠标的按钮状态。
然后，通过类似下面的代码片段，我们可以找出发生了什么。
if(event.bstate & BUTTON1_PRESSED)
printw("Left Button Pressed"); |
这就是鼠标接口的大部分内容。让我们创建相同的菜单并启用鼠标交互。为了简化，移除了按键处理。
示例 11. 使用鼠标访问菜单！！！
#include <ncurses.h>
#define WIDTH 30
#define HEIGHT 10
int startx = 0;
int starty = 0;
char *choices[] = { "Choice 1",
"Choice 2",
"Choice 3",
"Choice 4",
"Exit",
};
int n_choices = sizeof(choices) / sizeof(char *);
void print_menu(WINDOW *menu_win, int highlight);
void report_choice(int mouse_x, int mouse_y, int *p_choice);
int main()
{ int c, choice = 0;
WINDOW *menu_win;
MEVENT event;
/* Initialize curses */
initscr();
clear();
noecho();
cbreak(); //Line buffering disabled. pass on everything
/* Try to put the window in the middle of screen */
startx = (80 - WIDTH) / 2;
starty = (24 - HEIGHT) / 2;
attron(A_REVERSE);
mvprintw(23, 1, "Click on Exit to quit (Works best in a virtual console)");
refresh();
attroff(A_REVERSE);
/* Print the menu for the first time */
menu_win = newwin(HEIGHT, WIDTH, starty, startx);
print_menu(menu_win, 1);
/* Get all the mouse events */
mousemask(ALL_MOUSE_EVENTS, NULL);
while(1)
{ c = wgetch(menu_win);
switch(c)
{ case KEY_MOUSE:
if(getmouse(&event) == OK)
{ /* When the user clicks left mouse button */
if(event.bstate & BUTTON1_PRESSED)
{ report_choice(event.x + 1, event.y + 1, &choice);
if(choice == -1) //Exit chosen
goto end;
mvprintw(22, 1, "Choice made is : %d String Chosen is \"%10s\"", choice, choices[choice - 1]);
refresh();
}
}
print_menu(menu_win, choice);
break;
}
}
end:
endwin();
return 0;
}
void print_menu(WINDOW *menu_win, int highlight)
{
int x, y, i;
x = 2;
y = 2;
box(menu_win, 0, 0);
for(i = 0; i < n_choices; ++i)
{ if(highlight == i + 1)
{ wattron(menu_win, A_REVERSE);
mvwprintw(menu_win, y, x, "%s", choices[i]);
wattroff(menu_win, A_REVERSE);
}
else
mvwprintw(menu_win, y, x, "%s", choices[i]);
++y;
}
wrefresh(menu_win);
}
/* Report the choice according to mouse position */
void report_choice(int mouse_x, int mouse_y, int *p_choice)
{ int i,j, choice;
i = startx + 2;
j = starty + 3;
for(choice = 0; choice < n_choices; ++choice)
if(mouse_y == j + choice && mouse_x >= i && mouse_x <= i + strlen(choices[choice]))
{ if(choice == n_choices - 1)
*p_choice = -1;
else
*p_choice = choice + 1;
break;
}
} |