问Kivy Label:屏幕上到处都会触发on_touch_down事件

EN

from kivy.lang.builder import Builder
from kivy.app import App
from kivy.uix.label import Label

KV = """
BoxLayout:
    Button:
        text: "BUTTON"
"""

class MyFirstKivyApp(App):
    def build(self):
        self.box = Builder.load_string(KV)
        l = Label(text="LABEL")
        l.bind(on_touch_down=self.label_click)
        self.box.add_widget(l)
        return self.box

    def on_kv_post(self, base_widget):
        super().on_kv_post(base_widget)


    def label_click(self, w,touch):
        if w.collide_point(*touch.pos):
            print("Am I only triggered when touching the label ?")

MyFirstKivyApp().run()

from kivy.lang.builder import Builder
from kivy.app import App
from kivy.uix.label import Label

KV = """
BoxLayout:
    Button:
        text: "BUTTON"
"""

class MyFirstKivyApp(App):
    def build(self):
        self.box = Builder.load_string(KV)
        l = Label(text="[ref=label]Label[/ref]", markup=True)
        l.bind(on_ref_press=self.label_click)
        self.box.add_widget(l)
        return self.box

    def on_kv_post(self, base_widget):
        super().on_kv_post(base_widget)


    def label_click(self, w,event):
        print("Am I only triggered when touching the label ?")

MyFirstKivyApp().run()