Offline Maps API

The Offline Maps API provides complete offline map management functionality, including download, update, delete, and storage management.

ExpoGaodeMapOfflineModule

Offline map manager providing all offline map related functions.

Methods

getAvailableCities()

Get list of all downloadable cities.

tsx

const cities = await ExpoGaodeMapOfflineModule.getAvailableCities();

Returns

Promise<OfflineMapInfo[]> - Array of city information

Example

tsx

const cities = await ExpoGaodeMapOfflineModule.getAvailableCities();
console.log(`${cities.length} cities available`);

cities.forEach(city => {
  console.log(`${city.cityName}: ${(city.size / 1024 / 1024).toFixed(1)} MB`);
});

startDownload(options)

Start downloading offline map.

tsx

await ExpoGaodeMapOfflineModule.startDownload(options);

Parameters

options.cityCode: string - City code
options.allowCellular?: boolean - Allow downloads over cellular (default false)

Example

tsx

// WiFi only
await ExpoGaodeMapOfflineModule.startDownload({
  cityCode: '110000', // Beijing
  allowCellular: false,
});

// Allow cellular
await ExpoGaodeMapOfflineModule.startDownload({
  cityCode: '310000', // Shanghai
  allowCellular: true,
});

pauseDownload(cityCode)

Pause ongoing download.

tsx

await ExpoGaodeMapOfflineModule.pauseDownload(cityCode);

Parameters

cityCode: string - City code

Example

tsx

await ExpoGaodeMapOfflineModule.pauseDownload('110000');

resumeDownload(cityCode)

Resume paused download.

tsx

await ExpoGaodeMapOfflineModule.resumeDownload(cityCode);

Parameters

cityCode: string - City code

Example

tsx

await ExpoGaodeMapOfflineModule.resumeDownload('110000');

deleteMap(cityCode)

Delete offline map for specified city.

tsx

await ExpoGaodeMapOfflineModule.deleteMap(cityCode);

Parameters

cityCode: string - City code

Example

tsx

await ExpoGaodeMapOfflineModule.deleteMap('110000');
console.log('Beijing offline map deleted');

clearAll()

Clear all downloaded offline maps.

tsx

await ExpoGaodeMapOfflineModule.clearAll();

Example

tsx

await ExpoGaodeMapOfflineModule.clearAll();
console.log('All offline maps cleared');

getDownloadedMaps()

Get list of downloaded maps.

tsx

const maps = await ExpoGaodeMapOfflineModule.getDownloadedMaps();

Returns

Promise<OfflineMapInfo[]> - Array of downloaded city information

Example

tsx

const downloaded = await ExpoGaodeMapOfflineModule.getDownloadedMaps();
console.log(`${downloaded.length} cities downloaded`);

downloaded.forEach(city => {
  console.log(`✓ ${city.cityName}`);
});

getStorageInfo()

Get offline map storage information.

tsx

const storage = await ExpoGaodeMapOfflineModule.getStorageInfo();

Returns

Promise<StorageInfo> - Storage information object

Example

tsx

const storage = await ExpoGaodeMapOfflineModule.getStorageInfo();

console.log('Used:', (storage.usedSpace / 1024 / 1024).toFixed(2), 'MB');
console.log('Available:', (storage.availableSpace / 1024 / 1024).toFixed(2), 'MB');
console.log('Total:', (storage.totalSpace / 1024 / 1024).toFixed(2), 'MB');

checkUpdate(cityCode)

Check if map has updates for specified city.

tsx

const hasUpdate = await ExpoGaodeMapOfflineModule.checkUpdate(cityCode);

Parameters

cityCode: string - City code

Returns

Promise<boolean> - Whether update is available

Example

tsx

const hasUpdate = await ExpoGaodeMapOfflineModule.checkUpdate('110000');

if (hasUpdate) {
  console.log('Beijing map has new version');
  await ExpoGaodeMapOfflineModule.updateMap('110000');
} else {
  console.log('Beijing map is up to date');
}

updateMap(cityCode)

Update offline map for specified city.

tsx

await ExpoGaodeMapOfflineModule.updateMap(cityCode);

Parameters

cityCode: string - City code

Example

tsx

await ExpoGaodeMapOfflineModule.updateMap('110000');
console.log('Updating Beijing map');

Event Listeners

addDownloadProgressListener(callback)

Listen to download progress events.

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadProgressListener(callback);

Parameters

callback: (event: OfflineMapProgressEvent) => void - Callback function

Returns

Subscription - Subscription object, call remove() to unsubscribe

Event Object

tsx

interface OfflineMapProgressEvent {
  cityCode: string;
  cityName: string;
  progress: number; // 0-100
}

Example

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadProgressListener((event) => {
  console.log(`${event.cityName}: ${event.progress}%`);
  
  // Update UI progress bar
  setProgress(event.progress);
});

// Cleanup
return () => subscription.remove();

addDownloadCompleteListener(callback)

Listen to download completion events.

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadCompleteListener(callback);

Parameters

callback: (event: OfflineMapCompleteEvent) => void - Callback function

Event Object

tsx

interface OfflineMapCompleteEvent {
  cityCode: string;
  cityName: string;
}

Example

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadCompleteListener((event) => {
  Alert.alert('Download Complete', `${event.cityName} offline map downloaded`);
  loadData(); // Refresh list
});

return () => subscription.remove();

addDownloadErrorListener(callback)

Listen to download error events.

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadErrorListener(callback);

Parameters

callback: (event: OfflineMapErrorEvent) => void - Callback function

Event Object

tsx

interface OfflineMapErrorEvent {
  cityCode: string;
  cityName: string;
  error: string;
}

Example

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadErrorListener((event) => {
  console.error(`${event.cityName} download failed: ${event.error}`);
  Alert.alert('Download Failed', event.error);
});

return () => subscription.remove();

addDownloadPausedListener(callback)

Listen to download pause events.

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadPausedListener(callback);

Parameters

callback: (event: OfflineMapPausedEvent) => void - Callback function

Event Object

tsx

interface OfflineMapPausedEvent {
  cityCode: string;
  cityName: string;
}

Example

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadPausedListener((event) => {
  console.log(`${event.cityName} download paused`);
});

return () => subscription.remove();

addDownloadCancelledListener(callback)

Listen to download cancellation events.

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadCancelledListener(callback);

Parameters

callback: (event: OfflineMapCancelledEvent) => void - Callback function

Event Object

tsx

interface OfflineMapCancelledEvent {
  cityCode: string;
  cityName: string;
}

Example

tsx

const subscription = ExpoGaodeMapOfflineModule.addDownloadCancelledListener((event) => {
  console.log(`${event.cityName} download cancelled`);
});

return () => subscription.remove();

Type Definitions

OfflineMapInfo

City offline map information.

tsx

interface OfflineMapInfo {
  cityCode: string;      // City code
  cityName: string;      // City name
  size: number;          // Map size (bytes)
  status: OfflineMapStatus;
}

Example

tsx

const city: OfflineMapInfo = {
  cityCode: '110000',
  cityName: 'Beijing',
  size: 103809024, // ~99 MB
  status: 'DOWNLOADED',
};

OfflineMapStatus

Offline map status.

tsx

type OfflineMapStatus = 
  | 'NOT_DOWNLOADED'     // Not downloaded
  | 'DOWNLOADING'        // Downloading
  | 'PAUSED'            // Paused
  | 'DOWNLOADED'        // Downloaded
  | 'ERROR';            // Error

Example

tsx

const renderStatus = (status: OfflineMapStatus) => {
  switch (status) {
    case 'NOT_DOWNLOADED':
      return 'Not Downloaded';
    case 'DOWNLOADING':
      return 'Downloading';
    case 'PAUSED':
      return 'Paused';
    case 'DOWNLOADED':
      return 'Downloaded';
    case 'ERROR':
      return 'Error';
  }
};

StorageInfo

Storage space information.

tsx

interface StorageInfo {
  usedSpace: number;      // Used space (bytes)
  availableSpace: number; // Available space (bytes)
  totalSpace: number;     // Total space (bytes)
}

Example

tsx

const storage: StorageInfo = {
  usedSpace: 209715200,     // 200 MB
  availableSpace: 5368709120, // 5 GB
  totalSpace: 10737418240,   // 10 GB
};

const usagePercent = (storage.usedSpace / storage.totalSpace) * 100;
console.log(`Used ${usagePercent.toFixed(1)}%`);

Usage Examples

Basic Download Flow

tsx

import { useState, useEffect } from 'react';
import { ExpoGaodeMapOfflineModule } from 'expo-gaode-map';

function DownloadExample() {
  const [progress, setProgress] = useState(0);

  useEffect(() => {
    const sub = ExpoGaodeMapOfflineModule.addDownloadProgressListener((event) => {
      setProgress(event.progress);
    });

    return () => sub.remove();
  }, []);

  const handleDownload = async () => {
    await ExpoGaodeMapOfflineModule.startDownload({
      cityCode: '110000',
      allowCellular: false,
    });
  };

  return (
    <View>
      <Button title="Download Beijing Map" onPress={handleDownload} />
      <ProgressBar progress={progress} />
    </View>
  );
}

Storage Space Check

tsx

const handleDownload = async (city: OfflineMapInfo) => {
  // Check storage space
  const storage = await ExpoGaodeMapOfflineModule.getStorageInfo();
  
  if (storage.availableSpace < city.size) {
    Alert.alert(
      'Insufficient Storage',
      `Requires ${(city.size / 1024 / 1024).toFixed(1)} MB, ` +
      `available ${(storage.availableSpace / 1024 / 1024).toFixed(1)} MB`
    );
    return;
  }
  
  await ExpoGaodeMapOfflineModule.startDownload({
    cityCode: city.cityCode,
    allowCellular: false,
  });
};

Batch Update Check

tsx

const checkAllUpdates = async () => {
  const downloaded = await ExpoGaodeMapOfflineModule.getDownloadedMaps();
  const updates: string[] = [];
  
  for (const city of downloaded) {
    const hasUpdate = await ExpoGaodeMapOfflineModule.checkUpdate(city.cityCode);
    if (hasUpdate) {
      updates.push(city.cityName);
    }
  }
  
  if (updates.length > 0) {
    Alert.alert(
      'Updates Available',
      `Updates found for:\n${updates.join(', ')}`
    );
  } else {
    Alert.alert('Notice', 'All maps are up to date');
  }
};

Offline Maps API ​

ExpoGaodeMapOfflineModule ​

Methods ​

getAvailableCities() ​

startDownload(options) ​

pauseDownload(cityCode) ​

resumeDownload(cityCode) ​

deleteMap(cityCode) ​

clearAll() ​

getDownloadedMaps() ​

getStorageInfo() ​

checkUpdate(cityCode) ​

updateMap(cityCode) ​

Event Listeners ​

addDownloadProgressListener(callback) ​

addDownloadCompleteListener(callback) ​

addDownloadErrorListener(callback) ​

addDownloadPausedListener(callback) ​

addDownloadCancelledListener(callback) ​

Type Definitions ​

OfflineMapInfo ​

OfflineMapStatus ​

StorageInfo ​

Usage Examples ​

Basic Download Flow ​

Storage Space Check ​

Batch Update Check ​

Related Documentation ​

Offline Maps API

ExpoGaodeMapOfflineModule

Methods

getAvailableCities()

startDownload(options)

pauseDownload(cityCode)

resumeDownload(cityCode)

deleteMap(cityCode)

clearAll()

getDownloadedMaps()

getStorageInfo()

checkUpdate(cityCode)

updateMap(cityCode)

Event Listeners

addDownloadProgressListener(callback)

addDownloadCompleteListener(callback)

addDownloadErrorListener(callback)

addDownloadPausedListener(callback)

addDownloadCancelledListener(callback)

Type Definitions

OfflineMapInfo

OfflineMapStatus

StorageInfo

Usage Examples

Basic Download Flow

Storage Space Check

Batch Update Check

Related Documentation