English language

How to pronounce selected in English?

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let's say we have a to-do list app in
react
so somewhere in the app we would have a
component which displays the list of all
the to-do's
let's call this component to-do list
this component has a list of all the to
do's
and for every to-do it renders a to-do
item component
which displays the title of the to-do
now we want to be able to click on a
to-do item
to select it and then click a button in
the to-do list component which deletes
all the selected to do's
here is where lifting up the state comes
in handy
but let's first try to implement this
without thinking too much about it
so we might create a state variable in
the to do item component
which indicates if this true item
component is currently selected or not
then we might set an onclickhandler
which updates the state variable
then we just need to create the delete
button but here we stumble upon a
problem
because in the onclick function we want
to delete all the selected to-do's
but in order to do so we need to know
which these are
but the state which holds the
information which to-do items are
selected
is distributed over all the to-do item
components
and therefore we need to store the
information which to-do items are
selected
in the to-do list component we are
lifting the state
up from the to-do items to the to-do
list component
we can do that by passing a callback
function
down from the to-do list component to
the to-do item components
via the props which is called when the
to-do item is clicked
this callback then sets the state of the
to-do list component
so that it knows whether the to-do item
is selected or not
let's implement this so i have already
created the base project
and you can see we have the to-do list
here and we have already some to-do's
which i can select
or deselect and then we have the delete
button here
but when i click it nothing happens here
we have our app component which renders
a to-do list component
and the to-do list component has a state
which holds a list of to-do's
and it renders a to-do item component
for every
to-do and the to-do item component looks
like this
there you can see it has a state which
stores information if this
item is currently selected or not and
depending on that state
a different class name is used here we
have here this getclassname
function which returns different class
names depending on
whether the component is selected or not
so the first thing we need to do is we
need to go into the to-do list component
and yeah we want to lift the state up so
we add a new property to our to-dos
which we call selected and because in
the beginning
no to do should be selected we
initialize the property with the value
false
and now that we have lifted up our state
we can go into the to do item component
and there we can remove this selected
state variable
and we can also make this on click empty
and then we get an error because now it
doesn't know the variable selected
so we change this to the selected
property
of the to-do and now when we save it
then selecting the items doesn't work
anymore
because we have to put this
functionality into our to-do list
component but let's first see if this
worked so when i set
this to true then you can see that our
first to do
is marked as selected so now we know
that
lifting up the state was successful so i
set it
to false because we don't want that the
items are selected
initially let's recap real quick what we
just did
so previously inside our to-do item the
to-do item component had a
state variable created with the u-state
hook
and this was always true or false
depending on whether this true item
was selected or not and there was this
on click function which was set as the
on click handler
of the to-do item component and every
time when the user would click the to-do
item
component this on-click handler would
flip the value of this
selected state variable and remove the
information whether
a to-do item component is selected or
not
into the items of this list inside the
to-do list component
so every to-do now has a property which
is called selected
which determines if this to-do item
component
is selected or not and then inside our
to-do item
we can get the information from the
to-do that is passed
via the props so before we only use the
title property of our to-do
that's the title for example exercise or
laundry but now we also use the selected
property
and now it's time to again etch the
functionality
that when you click on a to do item that
it gets selected
and we do this by receiving a
on click prop so an onclickhandler
function
which is passed from the to-do-list
component down to our to-do item
component
and then we can remove this onclick
function here
and we set the onclickhandler to an
arrow function
which does nothing else than calling the
onclick function that we receive
as the prop
so on click we call the unclick function
and then we pass
in the id of the to do so to do dot
id and then we switch over to our to-do
list component and
there we create a function which we call
on to do item
clicked and it receives the
id of the to-do and then we pass it as
the on-click prop
to our to-do items so when
i add a console.log statement here
which says hello world
and then we also want to print the id
and then i open up my console
i reload and then when i click it you
can see
this on to do item clicked function is
called whenever i click on one of the to
do items
and we also receive the correct id here
and inside the onto do item click
function we want to use
the id that we receive as the argument
and then
search inside the to-do's list for the
to-do
which matches this id and then we want
to flip
the selected property so in order to
update our state which holds our to-do's
we have to first
make a copy of our to-do's so i'll
create a variable which i call new to
use
which is just the copy of our to-do's
and then we need to find the to-do
which matches the id that is passed as
the argument
and we can do so by calling the find
method on our new deduce array
and we pass in an arrow function which
checks if the
to-do id equals the id that is passed as
the argument
and then we just toggle or flip however
you want to name it
the selected property of the to do and
then we just have to set our new to use
array as the new state
and when i click on the to do items now
then you can see that they get
selected so our on to do item click
function
works as expected and finally we just
have to
add the functionality to the delete
button
so we create a new function which i call
delete selected
and then i create a new variable which i
call new to juice
which should only contain all the
to-do's that are currently not selected
so i can just write to do's and then
call the filter method on it
and then i supply it with an error
function which receives
a to do as its argument and then we
check if this
to do selected property
equals false and then this new toduce
variable will contain an array which
only consists of all the to do's which
are currently not selected
and then i set this as the new state so
i call set
to dose and i set it to new to do's
and then finally i just have to assign
this as the on click prop of our delete
button
so now when i select two items and i
click on the
delete button then you can see that the
items are removed and that's it for
today's video
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let's say we have a to-do list app in

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selected::adjective | Spocien Dictionary

selected

adjective

chosen in preference to another

Type	Words

How to pronounce selected in English?

selected::adjective | Spocien Dictionary

abandonment

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