InputActivity

InputActivity is a generic, reusable single-value input screen. It handles the UI and user input for one setting, then returns the value to the caller via startActivityForResult. It does not persist anything itself.

Overview

InputActivity is useful any time you need to ask the user for a single value: a text string, a choice from radio buttons or a dropdown, or an integer from a slider. It supports the same input widgets as SettingActivity, but is independent of SharedPreferences.

SettingActivity is a thin wrapper around InputActivity that adds SharedPreferences persistence, row-label updates, and changed_callback handling. Apps that only need the input UI can use InputActivity directly.

Basic Usage

from mpos import Activity, Intent, InputActivity

class MyApp(Activity):
    def ask_for_password(self):
        intent = Intent(activity_class=InputActivity)
        intent.putExtra("setting", {
            "title": "WiFi Password",
            "placeholder": "Enter password",
            "ui": "textarea"
        })
        intent.putExtra("value", "")
        self.startActivityForResult(intent, self.on_password_result)

    def on_password_result(self, result):
        if result and result.get("result_code"):
            password = result["data"]["value"]
            print("Password entered:", password)

Intent Extras

Required extras

setting (dict): Metadata describing the input.

Optional extras

value (string): Initial value to display. If omitted, setting["default_value"] is used, falling back to "".

Setting Dictionary Structure

The setting dict has the same shape as the one used by SettingActivity and SettingsActivity:

Required properties

title (string): Display name shown at the top of the input screen

Optional properties

key (string): Identifier returned in the result. Not used by InputActivity itself, but helpful for callers.
ui (string): UI type. Options: "textarea" (default), "radiobuttons", "dropdown", "slider", "activity"
ui_options (list): List of (label, value) tuples for radiobuttons and dropdown
placeholder (string): Placeholder text for textarea
default_value (string): Default value if no value extra is provided
note (string): Short informational text shown below the input widget
min (int): Minimum value for "slider" (default: 0)
max (int): Maximum value for "slider" (default: 100)
allow_deselect (bool): For radiobuttons, allow the user to un-select the active option (default: False)

Result Contract

InputActivity returns a result dict with the standard Activity result shape:

{
    "result_code": True,       # True on Save, False on Cancel/back
    "data": {
        "value": "<new_value>",
        "key": "<setting key>",
        "ui": "<ui type>"
    }
}

The caller is responsible for persisting or acting on the returned value.

UI Types

Textarea (default)

Text input with an on-screen keyboard. If the device has a camera, a "Scan data from QR code" button is also shown.

{
    "title": "API Key",
    "key": "api_key",
    "placeholder": "Enter your API key"
}

Radio Buttons

Mutually exclusive selection from a small list of options.

{
    "title": "Theme",
    "key": "theme",
    "ui": "radiobuttons",
    "ui_options": [
        ("Light", "light"),
        ("Dark", "dark"),
        ("Auto", "auto")
    ]
}

Compact selection from a larger list of options.

{
    "title": "Language",
    "key": "language",
    "ui": "dropdown",
    "ui_options": [
        ("English", "en"),
        ("German", "de"),
        ("French", "fr"),
        ("Spanish", "es")
    ]
}

Slider

Integer selection within a range.

{
    "title": "Volume",
    "key": "volume",
    "ui": "slider",
    "default_value": "50",
    "min": 0,
    "max": 100
}

Cancel and Back Handling

Pressing the Cancel button or swiping back returns:

{"result_code": False, "data": {"value": "...", "key": "...", "ui": "..."}}

Callers should check result.get("result_code") before using the value.