drab v0.4.1 Drab.Query
Drab module which provides interface to DOM objects on the server side. You may query (select/2
) or manipulate
(update/2
, insert/2
, delete/2
, execute/2
) the selected DOM object.
General syntax:
return = socket |> select(what, from: selector)
socket |> update(what, set: new_value, on: selector)
socket |> insert(what, into: selector)
socket |> delete(what, from: selector)
socket |> execute(what, on: selector)
where:
- socket - websocket used in connection
- selector - string with a DOM selector
- what - a representation of jQuery method; an atom (eg. :html, :val) or key/value pair (like attr: name).
An atom will launch the corresponding jQuey function without any arguments (eg.
.html()
). Key/value pair will launch the method named as the key with arguments taken from its value, sotext: "some"
becomes.text("some")
.
Object manipulation (update/2
, insert/2
, delete/2
, execute/2
) functions return socket.
Query select/2
returns either a found value (when using singular version of jQuery method, eg :html
), or
a Map of %{name|id|__undefined_XX => value}, when using plural - like :htmls
.
Select queries always refers to the page on which the event were launched. Data manipulation queries (update/2
,
insert/2
, delete/2
, execute/2
) changes DOM objects on this page as well, but they have a broadcast versions:
update!/2
, insert!/2
, delete!/2
and execute!/2
, which works the same, but changes DOM on every currently
connected browsers, which has opened the same URL, same controller, or having the same channel topic (see
Drab.Commander.broadcasting/1
to find out more).
Summary
Functions
Removes nodes, classes or attributes from selected node
Like Dom.Query.delete/2
, but broadcasts to all currently connected browsers
Execute given jQuery method on selector. To be used in case built-in method calls are not enough
Like Drab.Query.execute/2
, but broadcasts to all currently connected browsers, which have the same URL opened
Adds new node (html) or class to the selected object
Like Drab.Query.insert/2
, but broadcast to all currently connected browsers
Callback implementation for Drab.js_templates/0
Callback implementation for Drab.prerequisites/0
Returns a value get by executing jQuery method
on selected DOM object, or
a Map of %{name|id|_undefined[INCREMENT]: value} when method
name is plural, or a Map of
%{ method => returns_of_methods}
, when the method is :all
Finds the DOM object which triggered the event. To be used only in event handlers
Like Drab.Query.this/1
, but returns CSS ID of the object, so it may be used with broadcasting functions
Updates the DOM object corresponding to the jQuery method
Like Drab.Query.update/2
, but broadcasts to all currently connected browsers
Functions
Removes nodes, classes or attributes from selected node.
With selector and no options, removes it and all its children. With given from: selector
option, removes only
the content, but element remains in the DOM tree. With options class: class, from: selector
removes
class from given node(s). Given option prop: property
or attr: attribute
it is able to remove
property or attribute from the DOM node.
Waits for the browser to finish the changes and returns socket so it can be stacked.
Options:
- class: class - class name to be deleted
- prop: property - property to be removed from selected node(s)
- attr: attribute - attribute to be deleted from selected node(s)
- from: selector - DOM selector
Example:
socket |> delete(".btn") # remove all `.btn`
socket |> delete(from: "code") # empty all `<code>`, but node remains
socket |> delete(class: "btn-success", from: "#button")
Like Dom.Query.delete/2
, but broadcasts to all currently connected browsers.
Broadcast functions are asynchronous, do not wait for the reply from browsers, immediately return :sent
.
Execute given jQuery method on selector. To be used in case built-in method calls are not enough.
Waits for the browser to finish the changes and returns socket so it can be stacked.
socket |> execute(:click, on: "#mybutton")
socket |> execute(trigger: "click", on: "#mybutton")
socket |> execute("trigger("click")", on: "#mybutton")
Like Drab.Query.execute/2
, but broadcasts to all currently connected browsers, which have the same URL opened.
Broadcast functions are asynchronous, do not wait for the reply from browsers, immediately return :sent
.
Adds new node (html) or class to the selected object.
Waits for the browser to finish the changes and returns socket so it can be stacked.
Options:
- class: class - class name to be inserted
- into: selector - class will be added to specified selectors; only applies with
:class
- before: selector - creates html before the selector
- after: selector - creates html node after the selector
- append: selector - adds html to the end of the selector (inside the selector)
- prepend: selector - adds html to the beginning of the selector (inside the selector)
Example:
socket |> insert(class: "btn-success", into: "#button")
socket |> insert("<b>warning</b>", before: "#pane")
Like Drab.Query.insert/2
, but broadcast to all currently connected browsers.
Broadcast functions are asynchronous, do not wait for the reply from browsers, immediately return socket.
Callback implementation for Drab.js_templates/0
.
Callback implementation for Drab.prerequisites/0
.
Returns a value get by executing jQuery method
on selected DOM object, or
a Map of %{name|id|_undefined[INCREMENT]: value} when method
name is plural, or a Map of
%{ method => returns_of_methods}
, when the method is :all
.
Plural version uses name
attribute as a key, or id
, when there is no name
,
or __undefined_[INCREMENT]
, when neither id
or name
are specified.
In case the method requires an argument (like attr()
), it should be given as key/value
pair: method_name: “argument”.
Options:
- from: “selector” - DOM selector which is queried
- attr: “attribute” - DOM attribute
- prop: “property” - DOM property
- css: “css”
- data: “att” - returns the value of jQuery
data("attr")
method
Examples:
name = socket |> select(:val, from: "#name")
# "Stefan"
name = socket |> select(:vals, from: "#name")
# %{"name" => "Stefan"}
font = socket |> select(css: "font", from: "#name")
# "normal normal normal normal 14px / 20px \"Helvetica Neue\", Helvetica, Arial, sans-serif"
button_ids = socket |> select(datas: "button_id", from: "button")
# %{"button1" => 1, "button2" => 2}
Available jQuery methods:
html text val
width height
innerWidth innerHeight outerWidth outerHeight
position offset scrollLeft scrollTop
attr: val prop: val css: val data: val
Available jQuery plural methods:
htmls texts vals
widths heights
innerWidths innerHeights outerWidths outerHeights
positions offsets scrollLefts scrollTops
attrs: val props: val csses: val datas: val
:all
In case when method is :all
, executes all known methods on the given selector. Returns
Map %{name|id => medthod_return_value}
. The Map key are generated in the same way as those with plural methods.
socket |> select(:all, from: "span")
%{"first_span" => %{"height" => 16, "html" => "First span with class qs_2", "innerHeight" => 20, ...
Additionally, id
and name
attributes are included into a Map.
Finds the DOM object which triggered the event. To be used only in event handlers.
def button_clicked(socket, dom_sender) do
socket |> update(:text, set: "alread clicked", on: this(dom_sender))
socket |> update(attr: "disabled", set: true, on: this(dom_sender))
end
Do not use it with with broadcast functions (Drab.Query.update!
, Drab.Query.insert
, Drab.Query.delete
,
Drab.Query.execute!
), because it returns the exact DOM object. In case if you want to broadcast, use
Drab.Query.this!/1
instead.
Like Drab.Query.this/1
, but returns CSS ID of the object, so it may be used with broadcasting functions.
def button_clicked(socket, dom_sender) do
socket |> update!(:text, set: "alread clicked", on: this!(dom_sender))
socket |> update!(attr: "disabled", set: true, on: this!(dom_sender))
end
Raises exception when being used on the object without an ID.
Updates the DOM object corresponding to the jQuery method
.
In case when the method requires an argument (like attr()
), it should be given as key/value pair:
method_name: “argument”.
Waits for the browser to finish the changes, returns socket so it can be stacked.
Options:
- on: selector - DOM selector, on which the changes are made
- set: value - new value
- attr: attribute - DOM attribute
- prop: property - DOM property
- class: class - class name to be replaced by another class
- css: updates a given css
- data: sets the jQuery data storage by calling
data("key", value
); it does not update thedata-*
attribute
Examples:
socket |> update(:text, set: "saved...", on: "#save_button")
socket |> update(attr: "style", set: "width: 100%", on: ".progress-bar")
# the same effect:
socket |> update(css: "width", set: "100%", on: ".progress-bar")
Update can also switch the classes in DOM object (remove one and insert another):
socket |> update(class: "btn-success", set: "btn-danger", on: "#save_button")
You can also cycle between values - switch to the next value from the list or to the first element, if the actual value is not on the list:
socket |> update(:text, set: ["One", "Two", "Three"], on: "#thebutton")
socket |> update(css: "font-size", set: ["8px", "10px", "12px"], on: "#btn")
When cycling through the class
attribute, system will update the class if it is one in the list.
In the other case, it will add the first from the list.
socket |> update(:class, set: ["btn-success", "btn-danger"], on: "#btn")
Please notice that cycling is only possible on selectors which returns one node.
Another possibility is to toggle (add if not exists, remove in the other case) the class:
socket |> update(:class, toggle: "btn-success", on: "#btn")
Available jQuery methods: see Drab.Query.select/2
Like Drab.Query.update/2
, but broadcasts to all currently connected browsers.
Broadcast functions are asynchronous, do not wait for the reply from browsers, immediately return socket.