wehub-resource-sync
35 lines
835 B
Markdown
35 lines
835 B
Markdown
# Callbacks and Events
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`perspective.Table` allows for `on_update` and `on_delete` callbacks to be
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set—simply call `on_update` or `on_delete` with a reference to a function or a
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lambda without any parameters:
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```python
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def update_callback():
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print("Updated!")
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# set the update callback
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on_update_id = view.on_update(update_callback)
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def delete_callback():
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print("Deleted!")
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# set the delete callback
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on_delete_id = view.on_delete(delete_callback)
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# set a lambda as a callback
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view.on_delete(lambda: print("Deleted x2!"))
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```
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If the callback is a named reference to a function, it can be removed with
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`remove_update` or `remove_delete`:
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```python
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view.remove_update(on_update_id)
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view.remove_delete(on_delete_id)
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```
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Callbacks defined with a lambda function cannot be removed, as lambda functions
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have no identifier.
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