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Notify the child when there is onClick event in parent

I have a parent component that holds a string as a state. This string is composed with help from other child components.
Then the parent sends this string to a DisplayText component that displays it. However in the DisplayText component there is an internal state for that string and thus the user can change it however they like, and the result
const [myString, setMyString] = React.useState<string>('');
React.useEffect(() => {
// do some stuff with the string and save it
setMyString(string);
}, [...]);
<Textarea
value={myString}
onChange={(value) => setMyString(value)}
/>
(This is just basic React.) I would like to add a button in the parent component that forces the child to override any changes the user has made, and re-render the text coming from the parent. This happens naturally when the state in the parent changes, but how can you simulate the same effect when a button in the parent is clicked?
I could solve this by moving the internal state of editing the text from the child to the parent, so clicking the button can control that, but is there another way without doing so? Because the edited text shouldn't concern the parent. The second solution I thought of would be to force a re-render of the parent but the ways to do so are hacky (changing a dummy state).
Is there a simple solution to this?

Composing a string in multiple child components seems like a bad approach to me. But if you really need or want to do it that way, then adding a button in the partent component, that overwrites myString, should work. The props that refer to this value will update automatically. Just remove the internal state of the children, to have a 'single source of truth'.

That sounds like bad practice to me.
You should:
lift state up to parent and have a default value which is saved. Clicking the button should just reset to the default value.
If you need to change the parent state from one or more childs, you should pass down a setter function which sets the state in the parent.

How to emit a custom event from meta-data in Vue.js

I am trying to emit a custom event from a very rare situation.
I have a tab component where every slot inside has a name with 'row' and 'col' and each one corrisponds to <td>content here</td>, i must check inside the component if the slot is empty.
I am trying to emit a custom event 'no-content' only when the slot is actually empty.
My example
<my-component :meta-data="!$slots['td-'+row+'-'+col] ? $emit('no-content', 'td-'+row+'-'+col) : ''"
<slot :name="'td-'+row+'-'+col">
</slot>
</my-component>
is it actually possible to achieve this result with Vue.js? i tried myself and also searched for a case similar to mine but i found nothing.
PS: I actually spent a little more time trying to make it work but i had a problem with the component itself, so i started all over again but insted of using slots I work with an array of objects in input, now i reached the result I wanted to.
I'm gonna leave this here just in case someone else thinks about a solution with meta-data.

VUE component mutual interference

I have a vue component named "MText",
I insert the component twice,like this:
<MText></MText>
<MText></MText>
"MText" bind a click event to remove itself through "this.$el.remove();",but I click the second one,it is strange that the first one is removed;why?thanks everyone who can help me~~thx very much!

React/JSX - how to code an editable input with initial content provided via props that only updates its parent when submitted?

All the examples I have found that keep local state can't provide an initial value for the input. In my case a parent component retrieves field from a server and passes these to my input form where the fields shall be editable. But I don't want to pass each change back up the hierarchy if I can avoid it, rather only when the form is submitted (either via button or by pressing enter)
Update: the usage is as follows. Imagine a todo list. The top level holds the list and the detail component. When I click at the list the detail should update to show the selected todo text. That text should be editable.
So as far the the detail component goes the initial state of the input is the text from the list that gets passed down in props. It needs to change when a different todo in the list is selected. On the other hand I should be able to edit it and when submit triggered that todo text should be passed back up via a callback prop.
So I have to keep local state to collect the input, but I want that state to be initialized with the existing todo text from the list. If I use the Facebook example of an uncontrolled form, I find the edited text remains displayed when I switch to a different todo in the list. Maybe I'm doing it wrong or is it a conceptual problem? Using controlled input initializing the state in the constructor doesn't work either because the constructor only gets called once (not on each re-render)!

I solved the problem by using the lifecycle method componentWillReceiveProps(nextprops) where I can set the state to the new props. This method gets called each time a re-render becomes necessary - in my case because the parent changes the childs props.
See https://facebook.github.io/react/docs/react-component.html#componentwillreceiveprops

You can set the initial state based on the property passed in from the parent, then edit that state in the component before submitting with the form submission

How to programmatically add components or views inside other components/views in ember js

I have a component say {{component-1}} which gets called many times and creates a custom-texbox container and label as many times as it gets called.
Now whenever a user writes something in it a suggestion box should appear below it. Since the suggestion box can be reused everywhere i dont want to have a separate suggestion box for each {{component-1}}, rather i want to have another component called {{suggestion-box}} that gets inserted inside component-1 i.e. the textbox container.
I dont want {{suggestion-box}} to be inside dom at all since it is needed only when somebody types in it. I want to add/insert it into {{component-1}} when someone types. Instead of a component i even tried to use a view
Here are the different things i have tried and failed
Note:
suggestionBox is the component
textbox-container is an element inside {{component-1}}
Inside {{component-1}}this.$().find(".textbox-container").append(this.suggestionBox );where this.suggestionBox = suggestionBoxComponent.create(); I have event tried suggestionBoxView.create();It gives me the error that i one view cant be inserted into another and i need to use containerView
var tmp = Ember.Handlebars.compile('<div class=".suggestionBox"></div>');this.$().find('.textbox-container').append(tmp());I get the error called
Uncaught TypeError: Cannot read property 'push' of undefined
I even tried to use view instead of component i.e. make suggestionBox a view but then again i cannot insert one view inside another
I have tried a lot more things.
Few points:
I dont want alternate solutions of how textbox and suggestion box could be created
How to pass information from a component or a a template to a view? Say i do {{view "suggestion-box"}} inside component-1 template, how do i pass values to it? Say for components we pass in the context like this {{component1 sampleVar1=val1 sampleVar2=val2}}
i Want to know how to programmatically add a component or a view and if it is a view how to pass the data to it?
I dont want to use container-view since it will cause more complexities, however if your solution allows me to pass value from {{component-1}} to container-view and inturn pass it to corresponding childView1 and childView2 then that solution is acceptable
Just an update:
I even tried to use a view container inside the {{component-1}}
I also tried to use view block inside {{component-1}} i.e.
{{#view "view-name"}}
----earlier component elements here-----
{{/view}}
In both the above points "view-name" is a ContainerView which is getting inserted properly but the component element are not getting inserted

This can be achieved with a ContainerView and the viewName attribute. The component or view can access the ContainerView or any other view that is part of a template through its assigned viewName.
Example,
hbs
{{view Ember.ContainerView viewName="my-menu-container"}}
js - then from the component or view
this.get("my-menu-container").pushObject(suggestionBoxViewOrComponent);
http://emberjs.jsbin.com/yoyujeqi/1/edit
p.s. the context of the example is not relevant to the suggestion box, sorry about that, as it has been extracted from another answer related to adding a menu view dynamically.