flutter_mbtiles_extractor 0.0.5

A flutter plugin to extract the map tiles from an .mbtiles file.

example/lib/main.dart

import 'dart:async';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter_document_picker/flutter_document_picker.dart';
import 'package:flutter_mbtiles_extractor/mbtiles_extractor.dart';
import 'package:path/path.dart' as path;
import 'package:path_provider/path_provider.dart';

void main() => runApp(new MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => new _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _extractionStatus = 'Select a file to extract';
  bool _isBusy = false;
  File _selectedFile;

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    List<Widget> widgets = [];
    widgets.addAll([
      Text(
        'Extraction Status:\n $_extractionStatus\n',
        textAlign: TextAlign.center,
      ),
      _isBusy
          ? Padding(
              padding: EdgeInsets.all(16.0),
              child: LinearProgressIndicator(),
            )
          : MaterialButton(
              onPressed: () {
                if (_selectedFile == null || !_selectedFile.existsSync()) {
                  _launchFilePicker();
                } else {
                  _extractMBTilesFile();
                }
              },
              child: Text(_selectedFile != null ? "Extract" : "Select File"),
              color: Colors.blue,
            ),
    ]);
    if (_selectedFile != null && !_isBusy) {
      widgets.add(MaterialButton(
        onPressed: () {
          _clearSelectedFile();
        },
        child: Text("Deselect File"),
        color: Colors.red,
      ));
    }
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('MBTilesExtractor example app'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            mainAxisSize: MainAxisSize.min,
            children: widgets,
          ),
        ),
      ),
    );
  }

  Future<void> _extractMBTilesFile() async {
    String result;
    try {
      //Get directory of the application. This way works best for iOS.
      //The main point here is that the origin of the file is not relevant,
      //as long as you have access to the file.
      //Add path_provider dependency in example/pubspec.yaml to use the next function
      setState(() {
        _extractionStatus = "Extracting... Please wait!";
        _isBusy = true;
      });
      Directory appDirectory = await getApplicationDocumentsDirectory();
      print(_selectedFile.path);
      ExtractResult extractResult = await MBTilesExtractor.extractMBTilesFile(
        new ExtractRequest(
          _selectedFile.path,
          //This is the name of the file i was testing.
          desiredPath: appDirectory.path,
          //Example of final folder
          requestPermissions: true,
          //Vital in android
          removeAfterExtract: false,
          //Deletes the *.mbtiles file after the extraction is completed
          stopOnError: true,
          //Stops is one tile could not be extracted
          returnReference: true,
          //Returns the list of tiles once the extraction is completed
          onlyReference: false,
          //If true the reference of tiles is returned but the extraction is not performed
          schema: Schema.XYZ,
          //Flip y-axis to commonly used xyz (slippy map) tiling format.
        ),
      );
      result = """
      Result Code = ${extractResult.code}
      Extraction Message = ${extractResult.data}
      Tile Count = ${extractResult.tiles.length}
      Metadata = ${extractResult.metadata.toMap()}
      *Tile count only is displayed if reference is being returned
      """;
    } catch (ex, st) {
      print(ex);
      print(st);
    }
    setState(() {
      _extractionStatus = "$result";
      _isBusy = false;
    });
  }

  void _launchFilePicker() async {
    File file;
    String message = "Selection Cancelled";
    setState(() {
      this._isBusy = true;
    });
    try {
      FlutterDocumentPickerParams params = FlutterDocumentPickerParams(
        allowedFileExtensions: ["mbtiles"],
      );
      final filePath = await FlutterDocumentPicker.openDocument(params: params);
      if (filePath != null && filePath.isNotEmpty) {
        String extension = path.extension(filePath);
        if (extension == ".mbtiles") {
          file = File(filePath);
          message = "Ready to extract";
        } else {
          message = "Selected file is not mbtiles";
        }
      }
    } catch (ex) {
      message = "Selected file is not mbtiles";
    } finally {
      setState(() {
        this._extractionStatus = message;
        this._selectedFile = file;
        this._isBusy = false;
      });
    }
  }

  void _clearSelectedFile() {
    setState(() {
      this._selectedFile = null;
      this._extractionStatus = "File de-selected. Select a file to extract";
    });
  }
}