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cd11476592
* fix(msg): fill callback prototype lv_msg_subscribe_cb_t does not follow the callback conventions. Remove unused void* argument to fix that. * fix(msg): move subs_ll to gc roots * fix(msg): rename subsribe to subscribe * fix(msg): update docs * fix(msg): Add example_1 * fix(msg): fix include paths * fix(mgs): Fix python example typo and comments * fix(msg): LV_EVENT_MSG_RECEIVED event code
40 lines
1.2 KiB
Python
40 lines
1.2 KiB
Python
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# Define a message ID
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MSG_NEW_TEMPERATURE = const(1)
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# Define the object that will be sent as msg payload
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class Temperature:
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def __init__(self, value):
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self.value = value
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def __repr__(self):
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return f"{self.value} °C"
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def slider_event_cb(e):
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slider = e.get_target()
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v = slider.get_value()
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# Notify all subscribers (only the label now) that the slider value has been changed
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lv.msg_send(MSG_NEW_TEMPERATURE, Temperature(v))
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def label_event_cb(e):
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label = e.get_target()
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msg = e.get_msg()
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# Respond only to MSG_NEW_TEMPERATURE message
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if msg.get_id() == MSG_NEW_TEMPERATURE:
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payload = msg.get_payload()
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temprature = payload.__cast__()
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label.set_text(str(temprature))
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# Create a slider in the center of the display
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slider = lv.slider(lv.scr_act())
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slider.center()
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slider.add_event_cb(slider_event_cb, lv.EVENT.VALUE_CHANGED, None)
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# Create a label below the slider
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label = lv.label(lv.scr_act())
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label.add_event_cb(label_event_cb, lv.EVENT.MSG_RECEIVED, None)
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label.set_text("0%")
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label.align(lv.ALIGN.CENTER, 0, 30)
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# Subscribe the label to a message
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lv.msg_subscribe_obj(MSG_NEW_TEMPERATURE, label, None)
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