该程序的目标是必须在绿色矩形上单击鼠标,将窗口背景颜色更改为黄色或返回默认颜色,问题是颜色也可以从矩形外部更改。
鼠标点击应该只适用于矩形内。
问题出在我猜的 if else 语句中的 x 和 y 位置?
'Click Me' 文本也不会出现在按钮上。 在此处输入图像描述
按钮的正确 x 和 y 位置在此表中,单击链接。
require 'rubygems'
require 'gosu'
# Instructions: This code needs to be fixed and finished!
# The "Click Me" text is not appearing on the button, also
# the mouse_y co-ordinate should be shown along with the mouse_x one
# finally, a user has noticed the sometimes the button action occurs
# when you click out side the button area and vice-versa.
# determines whether a graphical widget is placed over others or not
module ZOrder
BACKGROUND, MIDDLE, TOP = *0..2
end
# Global constants
WIN_WIDTH = 640
WIN_HEIGHT = 400
class DemoWindow < Gosu::Window
# set up variables and attributes
def initialize
super(WIN_WIDTH, WIN_HEIGHT, false)
@background = Gosu::Color::WHITE
@button_font = Gosu::Font.new(20)
@info_font = Gosu::Font.new(10)
@locs = [60,60]
end
# Draw the background, the button with 'click me' text and text
# showing the mouse coordinates
def draw
# Draw background color
Gosu.draw_rect(0, 0, WIN_WIDTH, WIN_HEIGHT, @background, ZOrder::BACKGROUND, mode=:default)
# Draw the button
Gosu.draw_rect(50, 50, 100, 50, Gosu::Color::GREEN, ZOrder::TOP, mode=:default)
# Draw the button text
@button_font.draw("Click me", 60, 60, ZOrder::MIDDLE, 1.0, 1.0, Gosu::Color::BLACK)
# Draw the mouse position information
@info_font.draw("mouse_x: #{@locs[0]}", 0, 350, ZOrder::TOP, 1.0, 1.0, Gosu::Color::BLACK)
end
# this is called by Gosu to see if should show the cursor (or mouse)
def needs_cursor?
true
end
# If the button area (rectangle) has been clicked on change the background color
# also store the mouse_x and mouse_y attributes that we 'inherit' from Gosu
# you will learn about inheritance in the OOP unit - for now just accept that
# these are available and filled with the latest x and y locations of the mouse click.
def mouse_over_button(mouse_x, mouse_y)
if ((mouse_x > 50 and mouse_x < 150) or (mouse_y > 50 and mouse_x < 100))
true
else
false
end
end
# Where is mouse_x and mouse_y defined
def button_down(id)
case id
when Gosu::MsLeft
@locs = [mouse_x, mouse_y]
if mouse_over_button(mouse_x, mouse_y)
@background = Gosu::Color::YELLOW
else
@background = Gosu::Color::WHITE
end
end
end
end
# Lets get started!
DemoWindow.new.show