:construction: Scaffold a custom event handler example.

4 files changed, 124 insertions, 0 deletions

diff --git a/examples/04-custom-event-handlers/README.md b/examples/04-custom-event-handlers/README.md
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+++ b/examples/04-custom-event-handlers/README.md
@@ -0,0 +1 @@
+# 04 Custom Event Handlers
diff --git a/examples/04-custom-event-handlers/gleam.toml b/examples/04-custom-event-handlers/gleam.toml
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index 0000000..4368c0c
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+++ b/examples/04-custom-event-handlers/gleam.toml
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+name = "app"
+version = "1.0.0"
+target = "javascript"
+
+[dependencies]
+gleam_stdlib = "~> 0.34 or ~> 1.0"
+lustre = { path = "../../" }
+lustre_ui = "~> 0.3"
+
+[dev-dependencies]
+gleeunit = "~> 1.0"
diff --git a/examples/04-custom-event-handlers/manifest.toml b/examples/04-custom-event-handlers/manifest.toml
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index 0000000..4033048
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+++ b/examples/04-custom-event-handlers/manifest.toml
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+# This file was generated by Gleam
+# You typically do not need to edit this file
+
+packages = [
+  { name = "argv", version = "1.0.1", build_tools = ["gleam"], requirements = [], otp_app = "argv", source = "hex", outer_checksum = "A6E9009E50BBE863EB37D963E4315398D41A3D87D0075480FC244125808F964A" },
+  { name = "gleam_community_ansi", version = "1.4.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "gleam_community_colour"], otp_app = "gleam_community_ansi", source = "hex", outer_checksum = "FE79E08BF97009729259B6357EC058315B6FBB916FAD1C2FF9355115FEB0D3A4" },
+  { name = "gleam_community_colour", version = "1.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_community_colour", source = "hex", outer_checksum = "A49A5E3AE8B637A5ACBA80ECB9B1AFE89FD3D5351FF6410A42B84F666D40D7D5" },
+  { name = "gleam_erlang", version = "0.24.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "26BDB52E61889F56A291CB34167315780EE4AA20961917314446542C90D1C1A0" },
+  { name = "gleam_json", version = "0.7.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "thoas"], otp_app = "gleam_json", source = "hex", outer_checksum = "CB405BD93A8828BCD870463DE29375E7B2D252D9D124C109E5B618AAC00B86FC" },
+  { name = "gleam_otp", version = "0.9.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "5FADBBEC5ECF3F8B6BE91101D432758503192AE2ADBAD5602158977341489F71" },
+  { name = "gleam_stdlib", version = "0.34.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "1FB8454D2991E9B4C0C804544D8A9AD0F6184725E20D63C3155F0AEB4230B016" },
+  { name = "gleeunit", version = "1.0.2", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "D364C87AFEB26BDB4FB8A5ABDE67D635DC9FA52D6AB68416044C35B096C6882D" },
+  { name = "glint", version = "0.14.0", build_tools = ["gleam"], requirements = ["gleam_community_ansi", "gleam_stdlib", "snag", "gleam_community_colour"], otp_app = "glint", source = "hex", outer_checksum = "21AB16D5A50D4EF34DF935915FDBEE06B2DAEDEE3FCC8584C6E635A866566B38" },
+  { name = "lustre", version = "3.1.3", build_tools = ["gleam"], requirements = ["argv", "gleam_community_ansi", "gleam_erlang", "gleam_json", "gleam_otp", "gleam_stdlib", "glint"], source = "local", path = "../.." },
+  { name = "lustre_ui", version = "0.3.0", build_tools = ["gleam"], requirements = ["gleam_community_colour", "lustre", "gleam_stdlib"], otp_app = "lustre_ui", source = "hex", outer_checksum = "F81BE5D20153CFFC717C2C4687A19375A8613528908AF7069DDA1B929C8398B1" },
+  { name = "snag", version = "0.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "snag", source = "hex", outer_checksum = "54D32E16E33655346AA3E66CBA7E191DE0A8793D2C05284E3EFB90AD2CE92BCC" },
+  { name = "thoas", version = "0.4.1", build_tools = ["rebar3"], requirements = [], otp_app = "thoas", source = "hex", outer_checksum = "4918D50026C073C4AB1388437132C77A6F6F7C8AC43C60C13758CC0ADCE2134E" },
+]
+
+[requirements]
+gleam_stdlib = { version = "~> 0.34 or ~> 1.0" }
+gleeunit = { version = "~> 1.0" }
+lustre = { path = "../../" }
+lustre_ui = { version = "~> 0.3"}
diff --git a/examples/04-custom-event-handlers/src/app.gleam b/examples/04-custom-event-handlers/src/app.gleam
new file mode 100644
index 0000000..7bbb979
--- /dev/null
+++ b/examples/04-custom-event-handlers/src/app.gleam
@@ -0,0 +1,88 @@
+import gleam/dynamic
+import gleam/int
+import gleam/result
+import gleam/string
+import lustre
+import lustre/attribute
+import lustre/element.{type Element}
+import lustre/event
+// These examples are written with lustre_ui in mind. They'll work regardless,
+// but to see what lustre_ui can do make sure to run each of these examples with
+// the `--include-styles` flag:
+//
+//   $ gleam run -m lustre/try -- --include-styles
+//
+// In your own apps, make sure to add the `lustre_ui` dependency and include the
+// stylesheet somewhere.
+import lustre/ui
+import lustre/ui/aside
+
+// MAIN ------------------------------------------------------------------------
+
+pub fn main() {
+  let app = lustre.simple(init, update, view)
+  let assert Ok(_) = lustre.start(app, "#app", Nil)
+}
+
+// MODEL -----------------------------------------------------------------------
+
+type Model {
+  Model(value: String, length: Int, max: Int)
+}
+
+fn init(_) -> Model {
+  Model(value: "", length: 0, max: 10)
+}
+
+// UPDATE ----------------------------------------------------------------------
+
+pub opaque type Msg {
+  GotInput(value: String)
+  Reset
+}
+
+fn update(model: Model, msg: Msg) -> Model {
+  case msg {
+    GotInput(value) -> {
+      let length = string.length(value)
+      case length <= model.max {
+        True -> Model(..model, value: value, length: length)
+        False -> model
+      }
+    }
+    Reset -> Model(..model, value: "", length: 0)
+  }
+}
+
+// VIEW ------------------------------------------------------------------------
+
+fn view(model: Model) -> Element(Msg) {
+  let styles = [#("width", "100vw"), #("height", "100vh"), #("padding", "1rem")]
+  let length = int.to_string(model.length)
+  let max = int.to_string(model.max)
+  let on_input = fn(event) {
+    use target <- result.try(dynamic.field("target", dynamic.dynamic)(event))
+    use value <- result.try(dynamic.field("value", dynamic.string)(target))
+
+    // Decoding the `value` from anevent target is so common we provider a decoder
+    // for it already:
+    //
+    // use value <- result.try(event.value(event))
+
+    Ok(GotInput(value))
+  }
+
+  ui.centre(
+    [attribute.style(styles)],
+    ui.aside(
+      [aside.content_first(), aside.align_centre()],
+      ui.field(
+        [],
+        [element.text("Write a message:")],
+        ui.input([attribute.value(model.value), event.on("input", on_input)]),
+        [element.text(length <> "/" <> max)],
+      ),
+      ui.button([event.on_click(Reset)], [element.text("Reset")]),
+    ),
+  )
+}