Question

我正在学习kivy并且正在玩PONG示例。我添加了一个在玩家达到给定分数后出现的按钮。

    if self.player2.score ==2 or self.player1.score==2:
        self.serve_ball(vel=(0, 0))
        self.btn= Button()
        self.add_widget(self.btn)
        self.btn.bind(on_press=self.callback)

它绑定到一个重置得分和消息的函数回调，但是我在按下后尝试了几个删除按钮但没有成功的事情。

def callback(self, instance):
    self.player2.score=0
    self.player1.score=0
    self.message1=""
    self.message2=""
    self.serve_ball(vel=(4,0))
    self.remove_widget(self.btn)

任何想法如何？谢谢，这是完整的代码

from kivy.app import App 
from kivy.uix.widget import Widget
from kivy.uix.button import Button
from kivy.properties import StringProperty, NumericProperty, ReferenceListProperty, ObjectProperty
from kivy.vector import Vector
from kivy.clock import Clock
from random import randint


class PongPaddle(Widget):
    score = NumericProperty(0)

    def bounce_ball(self, ball):
        if self.collide_widget(ball):
            vx, vy = ball.velocity
            offset = (ball.center_y - self.center_y) / (self.height / 2)
            bounced = Vector(-1 * vx, vy)
            vel = bounced * 1.1
            ball.velocity = vel.x, vel.y + offset


class PongBall(Widget):

    #Vel of ball in x & y axis
    velocity_x = NumericProperty(0)
    velocity_y = NumericProperty(0)

    #referencia para usar como vector
    velocity = ReferenceListProperty(velocity_x,velocity_y)

    #funcion move  1 paso en intervalos para animar la bola
    def move(self):
        self.pos = Vector(*self.velocity) + self.pos


class PongGame(Widget):
    ball = ObjectProperty(None)
    player1 = ObjectProperty(None)
    player2 = ObjectProperty(None) 
    message2 = StringProperty("")
    message1 = StringProperty("")



    def callback(self, instance):
        self.player2.score=0
        self.player1.score=0
        self.message1=""
        self.message2=""
        self.serve_ball(vel=(4,0))
        self.remove_widget(self.btn)

    def serve_ball(self, vel=(4,0)):
        self.ball.center = self.center
        self.ball.velocity = vel

    def btnn(self, instance):
        self.remove_widget(self.btn)

    def update(self, dt):
        self.ball.move()

        #bounce of paddles
        self.player1.bounce_ball(self.ball)
        self.player2.bounce_ball(self.ball)

        #bounce ball off bottom or top
        if (self.ball.y < self.y) or (self.ball.top > self.top):
            self.ball.velocity_y *= -1

         #went of to a side to score point?
        if self.ball.x < self.x:
            self.player2.score += 1
            self.serve_ball(vel=(4, 0))
        if self.ball.x > self.width:
            self.player1.score += 1
            self.serve_ball(vel=(-4, 0))

        #emilio code
        if self.player2.score ==2 or self.player1.score==2:
            self.serve_ball(vel=(0, 0))
            self.btn= Button()
            self.add_widget(self.btn)
            self.btn.bind(on_press=self.callback)

            if self.player2.score == 2:
                self.message2= "player2 won!"


            if self.player1.score == 2:
                self.message1= "player1 won!"


    def on_touch_move(self, touch):
        if touch.x < self.width / 3:
            self.player1.center_y = touch.y
        if touch.x > self.width - self.width / 3:
            self.player2.center_y = touch.y


class PongApp(App):

    def build(self):
        game = PongGame()
        game.serve_ball()
        Clock.schedule_interval(game.update, 1.0 / 60.0)
        return game

if __name__=='__main__':
        PongApp().run()`

这是kv文件以防万一：

#:kivy 1.0.9


<PongBall>:
    size: 50, 50
    canvas:
        Ellipse:
            pos: self.pos
            size: self.size

<PongPaddle>:
    size: 25, 200
    canvas:
        Rectangle:
            pos:self.pos
            size:self.size
<PongGame>:
    ball: pong_ball
    player1: player_left
    player2: player_right
    canvas:
        Rectangle:
            pos: self.center_x - 5, 0
            size: 10, self.height

    Label:
        font_size: 70
        center_x: root.width / 4
        top: root.top - 50
        text: str(root.player1.score)
        color: (255,0,255,1)
    Label:
        font_size: 70
        center_x: root.width * 3 / 4
        top: root.top - 50
        text: str(root.player2.score)
        color: (255,0,255,1)
    Label:
        font_size: 40
        center_x: root.width * 3/4
        top: root.center_y
        text: str(root.message2)
        color: (0,255,0,1)
    Label:
        font_size: 40
        center_x: root.width / 4
        top: root.center_y
        text: str(root.message1)
        color: (0,255,0,1)

    PongBall:
        id: pong_ball
        center: self.parent.center


    PongPaddle:
        id: player_left
        x: root.x
        center_y: root.center_y


    PongPaddle:
        id: player_right
        x: root.width-self.width
        center_y: root.center_y

Answer 1

更新功能被多次调用，每次满足条件时，您都会创建另一个按钮。仅删除单击时创建的最后一个按钮...

这是你的错误：

if self.player2.score ==2 or self.player1.score==2:
    print 'WOO' # see how many times this is gonna be printed
    #make sure you don't get here more than once per game :)
    self.serve_ball(vel=(0, 0))
    self.btn= Button()
    self.add_widget(self.btn)
    self.btn.bind(on_press=self.callback)

kivy remove_widget没有删除

1 个答案: