filter example

Author: PGimenez

content/1.docs/4.examples/2.reactive-ui/filter-select-options.md

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+
+---
+title: Filter select options
+description: Enter text in a select menu to filter the available options.
+---
+
+## Filter select options
+
+**Enter text in a select menu to filter the available options.**
+
+To filter options in a select menu, you'll need to add some client-side Javascript to perform the filtering whenever the user types a new letter into the text field. Things to note in this example:
+
+- The option filtering is performed in the browser using the `filterFn` method we've defined with the @methods macro. This macro injects Javascript code into the browser
+- Reactive variables tagged with @in @out are mirrored in the browser as Javascript variables. In the browser, they are contained within the `Main_App_varMain_App_ReactiveModel` structure. You can examine this structure in the browser tools in the console
+
+```julia
+module App
+using GenieFramework
+
+@genietools
+
+@app begin
+    @out full_listofnames = ["Henry", "HenryJames", "Mark", "Jenny"]
+    @out listofnames = ["Henry", "HenryJames", "Mark", "Jenny"]
+    @in selected_name = ""
+    @in startlist_button = false
+
+    @onbutton startlist_button begin
+        listofnames = vcat(listofnames, ["Henry", "Mark", "Jenny"])
+    end
+end
+
+@methods begin
+    """
+filterFn: function(val, update, abort) {
+      if (val === '') {
+          update(() => {
+            Main_App_varMain_App_ReactiveModel.listofnames = Main_App_varMain_App_ReactiveModel.full_listofnames
+
+          })
+          return
+        }
+        update(() => {
+          const needle = val.toLowerCase()
+          Main_App_varMain_App_ReactiveModel.listofnames = Main_App_varMain_App_ReactiveModel.full_listofnames.filter(v => v.toLowerCase().indexOf(needle) > -1)
+        })
+      }
+"""
+end
+
+function ui()
+    [
+    column([
+        btn("Start list", @click(:startlist_button), size = "20px"),
+        select(:selected_name, options=:listofnames, emitvalue=true, clearable=true, useinput=true, counter = true, fillinput=true, filled = true, label="TraceID", var"@filter"="filterFn")
+        ])
+    ]
+end
+@page("/",ui)
+end
+```
+```