Kivy：自定义鼠标光标在越过应用程序窗口的左边缘或上边缘时的不良行为

Question

我想在 kivy 中制作一个自定义鼠标光标。 这是我目前拥有的：

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.scatter import Scatter
from kivy.core.window import Window
#Window.show_cursor = False

KV = """
FloatLayout
    BoxLayout
        MyTextInput
    MyMouse


<MyTextInput>:
    font_size: 40
    text: 'Some text'

<MyMouse>:
    mouse_im_size: mouse_im.size
    auto_bring_to_front: True

    do_rotation:False
    do_scale:False
    do_translation_y:False

    Image
        id: mouse_im
        size: 100, 100 / self.image_ratio
        source: 'cursor-pink.png'

"""

class MyTextInput(TextInput):
    pass

class MyMouse(Scatter):
    def __init__(self, **kwargs):
        Window.bind(mouse_pos=self.on_mouse_pos)
        super(MyMouse, self).__init__(**kwargs)

    def on_touch_down(self, *touch):
        return

    def on_mouse_pos(self, *args):
        x,y = args[1]
        self.pos = [x,y-self.mouse_im_size[1]]


class MyApp(App):
    def build(self):
        self.root = Builder.load_string(KV)

MyApp().run()

问题是当我将鼠标移出应用程序的左边缘或上边缘时，光标图像仍保留在应用程序内，我希望鼠标图像消失，就像我将鼠标移出右边缘或下边缘时一样.

问题似乎是on_mouse_pos() 仅在鼠标位于窗口内时才有效。

我found a way 获取鼠标在窗口外时的位置，但我不知道如何在我的任务中使用它。也许有更好的方法来做到这一点。

Answer 1

您可以通过使用Window 事件on_cursor_enter 和on_cursor_leave 并使用opacity 属性使光标可见/不可见来完成此操作：

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.scatter import Scatter
from kivy.core.window import Window
#Window.show_cursor = False

KV = """
FloatLayout
    BoxLayout
        MyTextInput
    MyMouse
        id: themouse


<MyTextInput>:
    font_size: 40
    text: 'Some text'

<MyMouse>:
    mouse_im_size: mouse_im.size
    auto_bring_to_front: True

    do_rotation:False
    do_scale:False
    do_translation_y:False

    Image
        id: mouse_im
        size: 100, 100 / self.image_ratio
        source: 'cursor-pink.png'

"""

class MyTextInput(TextInput):
    pass

class MyMouse(Scatter):
    def __init__(self, **kwargs):
        Window.bind(mouse_pos=self.on_mouse_pos)
        Window.bind(on_cursor_leave=self.on_cursor_leave)
        Window.bind(on_cursor_enter=self.on_cursor_enter)
        super(MyMouse, self).__init__(**kwargs)

    def on_touch_down(self, *touch):
        return

    def on_mouse_pos(self, *args):
        x,y = args[1]
        self.pos = [x,y-self.mouse_im_size[1]]

    def on_cursor_leave(self, *args):
        App.get_running_app().root.ids.themouse.opacity = 0

    def on_cursor_enter(self, *args):
        App.get_running_app().root.ids.themouse.opacity = 1


class MyApp(App):
    def build(self):
        self.root = Builder.load_string(KV)

MyApp().run()

我将themouse id 添加到MyMouse 小部件以完成此操作。

Answer 2

这是另一种方法，但它需要在您的基本布局周围设置边框：

from kivy.app import App
from kivy.clock import Clock
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.scatter import Scatter
from kivy.core.window import Window
#Window.show_cursor = False

KV = """
FloatLayout
    canvas.before:
        Color:
            rgba: (1, 0, 0, 1)
        Rectangle:
            size: self.size
            pos: self.pos
    FloatLayout
        id: mainlayout
        size_hint: (None, None)
        #pos: (50, 50)
        #pos_hint: {'center_x': 0.5, 'center_y': 0.5}
        canvas.before:
            Color:
                rgba: (0, 1, 0, 1)
            Rectangle:
                size: self.size
                pos: self.pos
        BoxLayout
            size_hint: (1.0, 0.2)
            pos_hint: {'center_x': 0.5, 'top': 1.0}
            MyTextInput
        StencilView:
            size_hint: (1.0, 1.0)
            pos_hint: {'x': 0, 'y': 0}
            MyMouse
                id: themouse


<MyTextInput>:
    font_size: 40
    text: 'Some text'

<MyMouse>:
    mouse_im_size: mouse_im.size
    auto_bring_to_front: True

    do_rotation:False
    do_scale:False
    do_translation_y:False

    Image
        id: mouse_im
        size: 100, 100 / self.image_ratio
        source: 'cursor-pink.png'

"""

class MyTextInput(TextInput):
    pass

class MyMouse(Scatter):
    def __init__(self, **kwargs):
        Window.bind(mouse_pos=self.on_mouse_pos)
        super(MyMouse, self).__init__(**kwargs)

    def on_touch_down(self, *touch):
        return

    def on_mouse_pos(self, *args):
        x,y = args[1]
        self.pos = [x,y-self.mouse_im_size[1]]

class MyApp(App):
    def build(self):
        self.mainlayout = None
        self.mymouse = None
        self.root = Builder.load_string(KV)
        Window.bind(size=self.do_size)
        Clock.schedule_once(self.do_size)

    def do_size(self, *args):
        if self.mainlayout is None:
            self.mainlayout = self.root.ids.mainlayout
        if self.mymouse is None:
            self.mymouse = self.root.ids.themouse

        self.mainlayout.size = (self.root.width - 2.0 * self.mymouse.mouse_im_size[0], self.root.height - 2.0 * self.mymouse.mouse_im_size[1])
        self.mainlayout.pos = self.mymouse.mouse_im_size

MyApp().run()

这使用 StencilView 将光标的绘图剪辑到 man 布局的内部。