pygame选择菜单导航，使用箭头键并返回

Question

I am trying to make it so I can generate a group of options to select from and using the up and down arrows the user can navigate between them the current option being highlighted and if you press enter it calls the function that option contains.

Excuse the mess, I had it cleaner, but was trying several things to try to get the intended result.

The selection function works fine by itself

def selection(text, selected_status, x, y, function):
if selected_status:
    fill_rect(black, x, y, display_width - x, font_size + 2)
    fill_rect( settings[3], x, y, display_width - x, font_size +2)
    message_to_screen("["+ text + "]", settings[3],  black, x, y)
    if event_handler() == pygame.K_RETURN:
        function()
        return True
elif not selected_status:
    fill_rect(black, x, y, display_width - x, font_size + 2)
    message_to_screen("["+ text + "]", black, settings[3], x, y)
    return False

The selection handler is the issue. it seems I have to hit the arrow keys at certain times in order for them to work. the event_handler just grabs the currently pressed key and returns it. overall it's just a broken mess.

def selection_handler(selection_param_array, x, y):
    text_array = selection_param_array[0]
    selected_status_array  = selection_param_array[1]
    function_array = selection_param_array[2]
    index = 0
    chosen = False
    original_y = y
    while not chosen:
        y = original_y

        for i in range(len(selected_status_array)):
            if selected_status_array[i] == selected_status_array[index]:
                selected_status_array[i] = True
            else:
                selected_status_array[i] = False
            selection(text_array[i], selected_status_array[i], x, y, function_array[i])
            y += font_size

        if event_handler() == pygame.K_UP and index > 0:
            index -= 1
        elif event_handler() == pygame.K_DOWN and index < len(selection_param_array):
            index += 1
        elif event_handler() == pygame.K_RETURN:
            chosen = True
            function_array[index]()
        pygame.display.update()

Answer 1

Instead of just checking whether a key is pressed down right now , you need to use pygame.event.get() to obtain all events that have occurred since the last pygame.event.get() call. The usual syntax is this:

for event in pygame.event.get():
    if event.type == pygame.KEYDOWN:
        if event.key == pygame.K_UP:
            index += 1
        elif event.key == pygame.K_DOWN:
            index -= 1
        elif event.key == pygame.K_RETURN:
            chosen = True
            function_array[index]()
            break
index %= len(selection_param_array)

Also, if you call from pygame.locals import * at the start of your program, you can omit pygame. from all of the keys and event types, so you get more readable code:

for event in pygame.event.get():
    if event.type == KEYDOWN:
        if event.key == K_UP:
            index += 1
        elif event.key == K_DOWN:
            index -= 1
        elif event.key == K_RETURN:
            chosen = True
            function_array[index]()
            break
index %= len(selection_param_array)

This replaces your if event_handler() == pygame.K_UP and index > 0: ... function_array[index]() code. Note that the code above will loop from the top to the bottom of the list when you are selecting things, I don't know if you want this. You can stop it from doing this by reintroducing your index comparisons on the event.key == lines and removing index %= len(selection_param_array) .