Example11MapTypes

Example11MapTypes - Switching Between Map Types

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This example demonstrates switching between different map types in OpenMapView, showing various OpenStreetMap-based tile sources with automatic attribution updates.

Features Demonstrated

• Five map types: Normal, Terrain, Humanitarian, Cycle, None
• Dynamic map type switching with buttons
• Automatic attribution text updates
• Tile cache clearing on map type change
• Material3 UI with button controls
• Error handling for invalid map types

Screenshot

Quick Start

Option 1: Run in Android Studio

1. Open the OpenMapView project in Android Studio
2. Select examples.Example11MapTypes from the run configuration dropdown
3. Click Run (green play button)
4. Deploy to your device or emulator

Option 2: Build and Install from Command Line

# From project root - build, install, and launch
./gradlew :examples:Example11MapTypes:installDebug

# Launch the app
adb shell am start -n de.afarber.openmapview.example11maptypes/.MainActivity

Code Highlights

Setting Map Type

val mapView = OpenMapView(context)

// Set map type
mapView.setMapType(MapType.TERRAIN)

// Get current map type
val currentType = mapView.getMapType()

Handle Invalid Types

try {
    mapView.setMapType(99)
} catch (e: IllegalArgumentException) {
    Toast.makeText(context, e.message, Toast.LENGTH_LONG).show()
}

Key Concepts

• MapType.NORMAL: Standard OpenStreetMap road map (default)
• MapType.TERRAIN: OpenTopoMap with elevation contours
• MapType.HUMANITARIAN: HOT OSM emphasizing humanitarian features
• MapType.CYCLE: CyclOSM showing cycling infrastructure
• MapType.NONE: No base map tiles displayed
• setMapType(): Change the map's tile source
• getMapType(): Query current map type

What to Test

1. Launch the app - Default Normal map type loads
2. Click Terrain - Switches to OpenTopoMap with contour lines
3. Click Humanitarian - Switches to red/orange humanitarian style
4. Click Cycle - Switches to CyclOSM with bike lanes
5. Click None - Removes all base tiles (overlays still visible)
6. Click Normal - Returns to standard OSM tiles
7. Check attribution - Bottom-right text updates for each source
8. Pan and zoom - New tiles load from current source

Map Types Reference

Type	Constant	Tile Source	Best For
Normal	MapType.NORMAL	OpenStreetMap Standard	General purpose street maps
Terrain	MapType.TERRAIN	OpenTopoMap	Hiking, elevation, topography
Humanitarian	MapType.HUMANITARIAN	Humanitarian OSM	Emergency response, infrastructure
Cycle	MapType.CYCLE	CyclOSM	Cycling routes, bike infrastructure
None	MapType.NONE	No tiles	Custom overlays only, performance testing

Technical Details

What Happens on Map Type Change

1. Tile source URL template is updated
2. Memory tile cache is cleared
3. Disk tile cache is cleared
4. Attribution text is updated
5. Map view is invalidated and redraws

Attribution by Map Type

• Normal: Map data from OpenStreetMap
• Terrain: Map data from OpenStreetMap | Map style: OpenTopoMap (CC-BY-SA)
• Humanitarian: Humanitarian OpenStreetMap Team
• Cycle: CyclOSM | Map data from OpenStreetMap

Performance Notes

• Cache clearing may cause momentary blank tiles
• New tiles download asynchronously
• Each map type has independent cache
• Some tile servers may have rate limits

Advanced Usage

Programmatic Map Type Selection

val mapTypes = listOf(
    MapType.NORMAL,
    MapType.TERRAIN,
    MapType.HUMANITARIAN,
    MapType.CYCLE
)

// Cycle through map types
var currentIndex = 0
button.setOnClickListener {
    currentIndex = (currentIndex + 1) % mapTypes.size
    mapView.setMapType(mapTypes[currentIndex])
}

Check Current Map Type

when (mapView.getMapType()) {
    MapType.NORMAL -> showNormalControls()
    MapType.TERRAIN -> showElevationLegend()
    MapType.CYCLE -> showCyclingStats()
    else -> hideSpecialControls()
}

Map Location

Default Center: Bochum, Germany (51.4661°N, 7.2491°E) at zoom 13.0

Test different map types at different locations:

• Terrain: Best viewed in mountainous areas (Alps, Black Forest)
• Humanitarian: Shows infrastructure in any populated area
• Cycle: Best in cities with cycling infrastructure