Skip to content

TimeZone

TimeZone is a utility class that provides timezone conversion and management functionality. It allows apps to convert between timezone names and POSIX timezone strings, and access the complete list of supported timezones.

Overview

TimeZone centralizes timezone-related operations in a single class with static methods. This provides:

  • Timezone Conversion - Convert timezone names to POSIX timezone strings
  • Timezone Listing - Access all available timezones
  • Simple API - Static methods for easy access without instantiation
  • Comprehensive Support - Supports all major world timezones

Architecture

TimeZone is implemented as a utility class using static methods:

class TimeZone:
    @staticmethod
    def timezone_to_posix_time_zone(timezone):
        """Convert timezone name to POSIX timezone string."""
        # Implementation

    @staticmethod
    def get_timezones():
        """Get list of all available timezone names."""
        # Implementation

No instance creation is needed - all methods are static and operate independently.

Usage

Basic Timezone Conversion

from mpos import TimeZone

# Convert timezone name to POSIX string
posix_tz = TimeZone.timezone_to_posix_time_zone('Europe/Berlin')
# Returns: 'CET-1CEST,M3.5.0,M10.5.0'

# Handle unknown timezone
posix_tz = TimeZone.timezone_to_posix_time_zone('Invalid/Zone')
# Returns: 'GMT0' (default fallback)

Getting Available Timezones

from mpos import TimeZone

# Get sorted list of all available timezones
timezones = TimeZone.get_timezones()
# Returns: ['Africa/Abidjan', 'Africa/Accra', ..., 'UTC', ...]

# Use in a timezone selector
for tz in timezones:
    print(tz)

Handling None Values

from mpos import TimeZone

# None timezone defaults to GMT0
posix_tz = TimeZone.timezone_to_posix_time_zone(None)
# Returns: 'GMT0'

API Reference

Static Methods

timezone_to_posix_time_zone(timezone)

Convert a timezone name to its POSIX timezone string.

Parameters: - timezone (str or None): Timezone name (e.g., 'Africa/Abidjan', 'Europe/Berlin') or None

Returns: str - POSIX timezone string (e.g., 'GMT0', 'CET-1CEST,M3.5.0,M10.5.0'). Returns 'GMT0' if timezone is None or not found.

Example:

posix_tz = TimeZone.timezone_to_posix_time_zone('Europe/Berlin')
# Returns: 'CET-1CEST,M3.5.0,M10.5.0'

get_timezones()

Get a sorted list of all available timezone names.

Returns: list - Sorted list of timezone names (e.g., ['Africa/Abidjan', 'Africa/Accra', ...])

Example:

all_timezones = TimeZone.get_timezones()
print(f"Available timezones: {len(all_timezones)}")

Practical Examples

Settings Screen with Timezone Selector

from mpos import Activity, TimeZone
import lvgl as lv

class SettingsActivity(Activity):
    def onCreate(self):
        screen = lv.obj()

        # Create dropdown with all timezones
        dropdown = lv.dropdown(screen)
        dropdown.set_options('\n'.join(TimeZone.get_timezones()))
        dropdown.set_width(300)

        self.setContentView(screen)

Timezone Validation

from mpos import TimeZone

def validate_timezone(tz_name):
    """Check if a timezone is valid."""
    available = TimeZone.get_timezones()
    return tz_name in available

# Usage
if validate_timezone('Europe/Berlin'):
    posix_tz = TimeZone.timezone_to_posix_time_zone('Europe/Berlin')
else:
    posix_tz = TimeZone.timezone_to_posix_time_zone(None)  # Fallback to GMT0

from mpos import TimeZone

def find_timezones(region):
    """Find all timezones in a region."""
    all_tz = TimeZone.get_timezones()
    return [tz for tz in all_tz if tz.startswith(region)]

# Usage
european_timezones = find_timezones('Europe')
# Returns: ['Europe/Amsterdam', 'Europe/Andorra', ..., 'Europe/Zurich']

Safe Timezone Conversion

from mpos import TimeZone

def get_posix_timezone(tz_name):
    """Get POSIX timezone with validation."""
    available = TimeZone.get_timezones()

    if tz_name not in available:
        print(f"Unknown timezone: {tz_name}, using GMT0")
        return TimeZone.timezone_to_posix_time_zone(None)

    return TimeZone.timezone_to_posix_time_zone(tz_name)

Implementation Details

File Structure

mpos/
├── time_zone.py       # Core TimeZone class
├── time_zones.py      # TIME_ZONE_MAP constant
└── __init__.py        # Exports TimeZone

Timezone Map

The TIME_ZONE_MAP is a dictionary mapping timezone names to POSIX timezone strings:

TIME_ZONE_MAP = {
    'Africa/Abidjan': 'GMT0',
    'Africa/Accra': 'GMT0',
    'Europe/Berlin': 'CET-1CEST,M3.5.0,M10.5.0',
    'Europe/London': 'GMT0BST,M3.5.0/1,M10.5.0',
    # ... many more timezones
}

Design Patterns

Static Method Utility Class

TimeZone uses static methods for a simple, functional API:

class TimeZone:
    @staticmethod
    def timezone_to_posix_time_zone(timezone):
        # No instance state needed
        return TIME_ZONE_MAP.get(timezone, "GMT0")

This pattern is ideal for stateless utility functions that don't require instance data.

  • DeviceInfo - Device hardware information
  • BuildInfo - OS version and build information
  • Preferences - Persistent user preferences (for storing timezone selection)

See Also