Why FocusNode needs to dispose in flutter?
I am kinda very confused when to use dispose in flutter. Are there any good tutorials about this?
In the cookbook https://flutter.io/docs/cookbook/forms/focus:
void dispose() {
// Clean up the focus node when the Form is disposed
myFocusNode.dispose();
super.dispose();
}
Why do I have to call myFocusNode.dispose();? What happened if I don't call it?
Please explain a bit clear or give me some obvious bad code examples showing bad results when not to call dispose for FocusNode or other situations instead of simply telling me this will cause memory leak...
Thanks a lot.
dart 
flutter asked Nov 14 '18 at 11:32
sgon00
252211
add a comment |
I am kinda very confused when to use dispose in flutter. Are there any good tutorials about this?
In the cookbook https://flutter.io/docs/cookbook/forms/focus:
void dispose() {
// Clean up the focus node when the Form is disposed
myFocusNode.dispose();
super.dispose();
}
Why do I have to call myFocusNode.dispose();? What happened if I don't call it?
Please explain a bit clear or give me some obvious bad code examples showing bad results when not to call dispose for FocusNode or other situations instead of simply telling me this will cause memory leak...
Thanks a lot.
dart flutter asked Nov 14 '18 at 11:32
sgon00
252211
add a comment |
I am kinda very confused when to use dispose in flutter. Are there any good tutorials about this?
In the cookbook https://flutter.io/docs/cookbook/forms/focus:
void dispose() {
// Clean up the focus node when the Form is disposed
myFocusNode.dispose();
super.dispose();
}
Why do I have to call myFocusNode.dispose();? What happened if I don't call it?
Please explain a bit clear or give me some obvious bad code examples showing bad results when not to call dispose for FocusNode or other situations instead of simply telling me this will cause memory leak...
Thanks a lot.
dart flutter asked Nov 14 '18 at 11:32
sgon00
252211
I am kinda very confused when to use dispose in flutter. Are there any good tutorials about this?
In the cookbook https://flutter.io/docs/cookbook/forms/focus:
void dispose() {
// Clean up the focus node when the Form is disposed
myFocusNode.dispose();
super.dispose();
}
Why do I have to call myFocusNode.dispose();? What happened if I don't call it?
Please explain a bit clear or give me some obvious bad code examples showing bad results when not to call dispose for FocusNode or other situations instead of simply telling me this will cause memory leak...
Thanks a lot.
dart flutter dart flutter asked Nov 14 '18 at 11:32
sgon00
252211
asked Nov 14 '18 at 11:32
sgon00
252211
asked Nov 14 '18 at 11:32
sgon00
252211
asked Nov 14 '18 at 11:32
sgon00
252211
asked Nov 14 '18 at 11:32
sgon00
252211
252211
add a comment |
add a comment |
1 Answer
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As from the documentation:
Focus nodes are long-lived objects. For example, if a stateful widget has a focusable child widget, it should create a FocusNode in the State.initState method, and dispose it in the State.dispose method, providing the same FocusNode to the focusable child each time the State.build method is run. In particular, creating a FocusNode each time State.build is invoked will cause the focus to be lost each time the widget is built.
In other words, disposing them ensures that the node invokes focus correctly each time the widget is built, there are no issues with other Widgets which invoke focus and it also preserves performance.
answered Nov 14 '18 at 15:16
SnakeyHips
550111
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
add a comment |
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1 Answer
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1 Answer
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As from the documentation:
Focus nodes are long-lived objects. For example, if a stateful widget has a focusable child widget, it should create a FocusNode in the State.initState method, and dispose it in the State.dispose method, providing the same FocusNode to the focusable child each time the State.build method is run. In particular, creating a FocusNode each time State.build is invoked will cause the focus to be lost each time the widget is built.
In other words, disposing them ensures that the node invokes focus correctly each time the widget is built, there are no issues with other Widgets which invoke focus and it also preserves performance.
answered Nov 14 '18 at 15:16
SnakeyHips
550111
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
add a comment |
As from the documentation:
Focus nodes are long-lived objects. For example, if a stateful widget has a focusable child widget, it should create a FocusNode in the State.initState method, and dispose it in the State.dispose method, providing the same FocusNode to the focusable child each time the State.build method is run. In particular, creating a FocusNode each time State.build is invoked will cause the focus to be lost each time the widget is built.
In other words, disposing them ensures that the node invokes focus correctly each time the widget is built, there are no issues with other Widgets which invoke focus and it also preserves performance.
answered Nov 14 '18 at 15:16
SnakeyHips
550111
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
add a comment |
As from the documentation:
Focus nodes are long-lived objects. For example, if a stateful widget has a focusable child widget, it should create a FocusNode in the State.initState method, and dispose it in the State.dispose method, providing the same FocusNode to the focusable child each time the State.build method is run. In particular, creating a FocusNode each time State.build is invoked will cause the focus to be lost each time the widget is built.
In other words, disposing them ensures that the node invokes focus correctly each time the widget is built, there are no issues with other Widgets which invoke focus and it also preserves performance.
answered Nov 14 '18 at 15:16
SnakeyHips
550111
As from the documentation:
Focus nodes are long-lived objects. For example, if a stateful widget has a focusable child widget, it should create a FocusNode in the State.initState method, and dispose it in the State.dispose method, providing the same FocusNode to the focusable child each time the State.build method is run. In particular, creating a FocusNode each time State.build is invoked will cause the focus to be lost each time the widget is built.
In other words, disposing them ensures that the node invokes focus correctly each time the widget is built, there are no issues with other Widgets which invoke focus and it also preserves performance.
answered Nov 14 '18 at 15:16
SnakeyHips
550111
answered Nov 14 '18 at 15:16
SnakeyHips
550111
answered Nov 14 '18 at 15:16
SnakeyHips
550111
answered Nov 14 '18 at 15:16
SnakeyHips
550111
550111
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
add a comment |
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
Thanks for your reply. Actually I want to see some code which causes observable problem when not disposing FocusNode. And I am not sure how to address and debug the issue when I forget to dispose FocusNode.
– sgon00
Nov 16 '18 at 6:03
add a comment |
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