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I have a kv segment that is within my python code.

What I want to do is select this button and animate it. The animation itself is triggered by pressing NoButton. NoButton has a class of itself that is child to the root widget class. Unfortunately despite having been able to successfully reference id out of the kv code, i can't seem actually make use of it.

Pressing NoButton results in absolutely nothing. No errors, nothing. If I try to print the id what i get is the location of the button it references:

<__main__.MainButton object at 0x7fd5db0d5590>

Here is a snippet of the kv code:

<MainClass>:
<MainScreen>:
    id: main

    AnchorLayout:
        size: root.size
        anchor_x: 'center'
        anchor_y: 'center'
        padding: 0, 0, 0, 50
        MainButton:
            id: pics
            rgba: 1,5,1,1
            size_hint_x: None
            size_hint_y: None
            height: main.height / 1.5
            width: main.width / 1.5

and the python:

class MainScreen(Screen):
    pass

class MainButton(Button):
    pass

class NoButton(ButtonBehavior, Image, MainClass):
    def on_press(self):     
        anim = Animation(x=300, y=300)
        anim.start(MainButton())
        print(MainScreen().ids.pics)

You'll notice anim.start references the class rather than the id here. Unfortunately it produces the same result; nothing at all.

Creating pics as an object property and declaring that in kv fails to work too.

I really am completely clueless here. I've looked through the few questions that are slightly similar but there really isn't much when it comes to help/guides for in depth kivy development.

I'm using Python 3.5.3 and Kivy 1.9.2-dev0

Would appreciate any help/advice or pointers in the right direction :)

TellMeWhy
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1 Answers1

2

You are creating new objects instead of referencing the exiting ones

    anim.start(MainButton()) #new MainButton Object :(
    print(MainScreen().ids.pics) #also a new MainScreen object

I don't see in your code where is NoButton, but should get a hold on the MainScreen instance and from it extract the MainButton instance

main_button = main_screen.ids.pics
ani.start(main_button)

If you'll post a runable example I'll might be able to help you more, I guess...

Yoav Glazner
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