Newly created preact Component retains UI state of old component (different from react)
I have a simple Preact component which contains a checkbox:
class Cb extends Component
render()
return (<div>Checkbox: <input type="checkbox" /></div>);
In a parent Component, this Cb is conditionally added like this:
this.state.show ? <Cb /> : <div>Nothing</div>
Now for the strange part: If you follow these steps:
- Check the checkbox
- Toggle
state.showin the parentComponent, removing theCb - Toggle
state.showin the parentComponentagain, creating a newCb
Then the newly created checkbox is still checked!
How is this possible? The checkbox is truely removed and a completely new Cb instance is created (I checked using log messages in the constructor). Where is this state stored?
Additional weirdness: The behavior is different in React (there, the newly created checkbox is not checked).
Here are two Codepens with the same code in Preact and React, where you can compare the behaviors.
reactjs preact
asked Nov 10 '18 at 21:12
GeierGeier
774314
add a comment |
I have a simple Preact component which contains a checkbox:
class Cb extends Component
render()
return (<div>Checkbox: <input type="checkbox" /></div>);
In a parent Component, this Cb is conditionally added like this:
this.state.show ? <Cb /> : <div>Nothing</div>
Now for the strange part: If you follow these steps:
- Check the checkbox
- Toggle
state.showin the parentComponent, removing theCb - Toggle
state.showin the parentComponentagain, creating a newCb
Then the newly created checkbox is still checked!
How is this possible? The checkbox is truely removed and a completely new Cb instance is created (I checked using log messages in the constructor). Where is this state stored?
Additional weirdness: The behavior is different in React (there, the newly created checkbox is not checked).
Here are two Codepens with the same code in Preact and React, where you can compare the behaviors.
reactjs preact
asked Nov 10 '18 at 21:12
GeierGeier
774314
add a comment |
I have a simple Preact component which contains a checkbox:
class Cb extends Component
render()
return (<div>Checkbox: <input type="checkbox" /></div>);
In a parent Component, this Cb is conditionally added like this:
this.state.show ? <Cb /> : <div>Nothing</div>
Now for the strange part: If you follow these steps:
- Check the checkbox
- Toggle
state.showin the parentComponent, removing theCb - Toggle
state.showin the parentComponentagain, creating a newCb
Then the newly created checkbox is still checked!
How is this possible? The checkbox is truely removed and a completely new Cb instance is created (I checked using log messages in the constructor). Where is this state stored?
Additional weirdness: The behavior is different in React (there, the newly created checkbox is not checked).
Here are two Codepens with the same code in Preact and React, where you can compare the behaviors.
reactjs preact
asked Nov 10 '18 at 21:12
GeierGeier
774314
I have a simple Preact component which contains a checkbox:
class Cb extends Component
render()
return (<div>Checkbox: <input type="checkbox" /></div>);
In a parent Component, this Cb is conditionally added like this:
this.state.show ? <Cb /> : <div>Nothing</div>
Now for the strange part: If you follow these steps:
- Check the checkbox
- Toggle
state.showin the parentComponent, removing theCb - Toggle
state.showin the parentComponentagain, creating a newCb
Then the newly created checkbox is still checked!
How is this possible? The checkbox is truely removed and a completely new Cb instance is created (I checked using log messages in the constructor). Where is this state stored?
Additional weirdness: The behavior is different in React (there, the newly created checkbox is not checked).
Here are two Codepens with the same code in Preact and React, where you can compare the behaviors.
reactjs preact
reactjs preact
asked Nov 10 '18 at 21:12
GeierGeier
774314
asked Nov 10 '18 at 21:12
GeierGeier
774314
asked Nov 10 '18 at 21:12
GeierGeier
774314
asked Nov 10 '18 at 21:12
GeierGeier
774314
asked Nov 10 '18 at 21:12
GeierGeier
774314
774314
add a comment |
add a comment |
1 Answer
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This has to do with how Preact recycles components. There is a GitHub issue along the same lines as what your question is. Now to fix the problem you will have to reset the checked value in componentWillUnmount
componentWillUnmount ()
this.cb.checked = false;
Where this.cb is a ref to the checkbox.
Working Codepen with the modification.
I made the checkbox a ref because there is another issue with componentWillUnMount and using querySelector (and its also shorter to type)
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
This has to do with how Preact recycles components. There is a GitHub issue along the same lines as what your question is. Now to fix the problem you will have to reset the checked value in componentWillUnmount
componentWillUnmount ()
this.cb.checked = false;
Where this.cb is a ref to the checkbox.
Working Codepen with the modification.
I made the checkbox a ref because there is another issue with componentWillUnMount and using querySelector (and its also shorter to type)
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
add a comment |
This has to do with how Preact recycles components. There is a GitHub issue along the same lines as what your question is. Now to fix the problem you will have to reset the checked value in componentWillUnmount
componentWillUnmount ()
this.cb.checked = false;
Where this.cb is a ref to the checkbox.
Working Codepen with the modification.
I made the checkbox a ref because there is another issue with componentWillUnMount and using querySelector (and its also shorter to type)
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
add a comment |
This has to do with how Preact recycles components. There is a GitHub issue along the same lines as what your question is. Now to fix the problem you will have to reset the checked value in componentWillUnmount
componentWillUnmount ()
this.cb.checked = false;
Where this.cb is a ref to the checkbox.
Working Codepen with the modification.
I made the checkbox a ref because there is another issue with componentWillUnMount and using querySelector (and its also shorter to type)
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
This has to do with how Preact recycles components. There is a GitHub issue along the same lines as what your question is. Now to fix the problem you will have to reset the checked value in componentWillUnmount
componentWillUnmount ()
this.cb.checked = false;
Where this.cb is a ref to the checkbox.
Working Codepen with the modification.
I made the checkbox a ref because there is another issue with componentWillUnMount and using querySelector (and its also shorter to type)
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
answered Nov 30 '18 at 18:13
pmkropmkro
1,369617
1,369617
add a comment |
add a comment |
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