PLECK lesson 49 · suggested week 10, day 4
Connect choices without duplicate handlers
Objective. Bind button indexes and update a view from state.
Godot Engine Standard desktop editor 4.7.2-stable, GDScript (Godot 4), Compatibility renderer. Headless Godot 4.7.2.stable.official.ed1daf0bf passed 106 assertions on the supplied scaffolds, including malformed JSON saves. Audio used the Dummy driver and a synthetic WAV, not a speaker. The visual editor, browser export, and signed-in submission were not tested. The desk still does not run a student's own upload.
About 55 minutes. The due date is chosen by a parent.
Branch diagrams, dialogue data, containers and keyboard focus
Suggested pace: Recall and predict 5 min; Read instruction and scaffold 12 min; Build or design the assigned artifact 25 min; Run acceptance tests 8 min; Explain and checkpoint 5 min.
Materials: Godot Standard 4.7.2 desktop editor (GDScript, Compatibility renderer), Local course folder and prior checkpoint, No paid assets or public account required.
Comes after VGC-L048.
A button’s pressed signal does not say which story choice it represents. C-DIALOGUE binds index zero or one when connecting each button. _choose looks up the current page’s choices, validates the index, changes page and refreshes the view. _show hides an unused second button on one-choice pages. Connect buttons once in _ready; repeatedly connecting every time a passage is shown can trigger multiple transitions from one press. The page variable is state and the label is only its view.
Worked example
A passage with key entrance can display any original sentence. Its choice ["Read the note", "note"] links to a stable note key even if the sentence is later edited. Scaffold C-DIALOGUE — Data-driven branching dialogue without personal data Setup: Create Control root Dialogue with VBoxContainer Box containing Label Line and Buttons A and B. Set Box anchors to full rect; Line autowrap if needed. Attach script to Dialogue. Data keys are fictional scene IDs. All three screens can fit in 640x360. This is a self-contained example; replace story text in the assignment. ```gdscript extends Control var page: String = "start" var story: Dictionary = { "start": {"text": "Two paths enter the archive.", "choices": [["Ask the keeper", "keeper"], ["Read a sign", "sign"]]}, "keeper": {"text": "The keeper offers a map.", "choices": [["Return", "start"]]}, "sign": {"text": "Quiet room to the east.", "choices": [["Return", "start"]]} } func _ready() -> void: $Box/A.pressed.connect(_choose.bind(0)) $Box/B.pressed.connect(_choose.bind(1)) _show() func _show() -> void: var entry: Dictionary = story[page] $Box/Line.text = entry["text"] var buttons: Array[Button] = [$Box/A, $Box/B] for i in range(buttons.size()): buttons[i].visible = i < entry["choices"].size() if buttons[i].visible: buttons[i].text = entry["choices"][i][0] $Box/A.grab_focus() func _choose(index: int) -> void: var choices: Array = story[page]["choices"] if index < 0 or index >= choices.size(): return page = str(choices[index][1]) _show() ```
Data-driven branching dialogue without personal data
GDScript (Godot 4, not Scratch, Python, JavaScript or C#). Scaffold C-DIALOGUE. Copy starts from this text. The desk does not run it.
Scene and node setup
Create Control root Dialogue with VBoxContainer Box containing Label Line and Buttons A and B. Set Box anchors to full rect; Line autowrap if needed. Attach script to Dialogue. Data keys are fictional scene IDs. All three screens can fit in 640x360. This is a self-contained example; replace story text in the assignment.
extends Control
var page: String = "start"
var story: Dictionary = {
"start": {"text": "Two paths enter the archive.", "choices": [["Ask the keeper", "keeper"], ["Read a sign", "sign"]]},
"keeper": {"text": "The keeper offers a map.", "choices": [["Return", "start"]]},
"sign": {"text": "Quiet room to the east.", "choices": [["Return", "start"]]}
}
func _ready() -> void:
$Box/A.pressed.connect(_choose.bind(0))
$Box/B.pressed.connect(_choose.bind(1))
_show()
func _show() -> void:
var entry: Dictionary = story[page]
$Box/Line.text = entry["text"]
var buttons: Array[Button] = [$Box/A, $Box/B]
for i in range(buttons.size()):
buttons[i].visible = i < entry["choices"].size()
if buttons[i].visible:
buttons[i].text = entry["choices"][i][0]
$Box/A.grab_focus()
func _choose(index: int) -> void:
var choices: Array = story[page]["choices"]
if index < 0 or index >= choices.size():
return
page = str(choices[index][1])
_show()
Checks to run in the editor
- Both start choices work.
- Return works from each branch; hidden B cannot trigger a nonexistent choice.
Native Godot 4.7.2.stable.official.ed1daf0bf headless compile and representative node-tree/runtime tests passed; see native-qa-results.json. Visual UI, audible output, exports and website submission still need separate checks.
Connect choices without duplicate handlers — evidence task
- 1. Implement the story with C-DIALOGUE’s connection pattern.
- 2. Visit both branches and return repeatedly.
Deliverable. Runnable branching-story project and repeat-navigation log.
Acceptance checks
- VGC-L049-T1. One press produces one transition.
- VGC-L049-T2. A one-choice passage cannot activate a stale second choice.
Understanding question. Why connect once rather than inside _show?
Include a downloadable project ZIP with project.godot, .tscn, .gd and original asset files when code changes. A private, teacher-accessible download link to that ZIP is equivalent. Screenshots or a playthrough do not replace editable source.
If this is still shaky. Use three screens and two buttons with C-DIALOGUE. Draw every link before writing dialogue. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
Optional extra. Create a branch that rejoins the main path while preserving a meaningful choice. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
Turn in typed notes and a JPEG, PNG, or WebP screenshot. One https address is stored as text and is not opened, extracted, or run. An MP3, WAV, M4A, MP4, or WebM file up to 4 MB can show a demo. The demo does not replace editable source. Zip and code files are refused. If there is no private link, keep the project on the family computer and review the code in person.
- Godot step by step: nodes, scenes, GDScript, input, signals
Free public documentation, no account. Same class help is available within the desktop editor.
· Opening this link does not submit the lesson.
This is a preview. A parent assigns the lesson and chooses the due date after the student is enrolled. The answer key is not on this page.
