bluetooth_print_plus 2.4.5
bluetooth_print_plus: ^2.4.5 copied to clipboard
bluetooth_print_plus is a flutter plugin for bluetooth thermal printer, support Android & iOS, supports tspl/tsc、cpcl、esc pos.
Bluetooth Print Plus #
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Introduction #
Bluetooth Print Plus is a Bluetooth plugin used to print thermal printers in Flutter, a new mobile SDK to help developers build bluetooth thermal printer apps for iOS and Android.
Important, important, important. First, you need to run the demo to confirm the printer command type ! ! ! now support tspl/tsc、cpcl、esc pos. If this plugin is helpful to you, please give it a like, Thanks.Buy Me A Coffee/请我喝杯咖啡 #
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Plan #
Version | plan |
---|---|
1.1.x | blue and tsc command, esc print image command |
1.5.x | support cpcl command |
2.x.x | improve esc command |
3.x.x | support zpl command |
Features #
Android | iOS | Description | |
---|---|---|---|
scan | ✅ | ✅ | Starts a scan for Bluetooth Low Energy devices. |
connect | ✅ | ✅ | Establishes a connection to the device. |
disconnect | ✅ | ✅ | Cancels an active or pending connection to the device. |
state | ✅ | ✅ | Stream of state changes for the Bluetooth Device. |
Usage #
To use this plugin : #
- add the dependency to your pubspec.yaml file.
dependencies:
flutter:
sdk: flutter
bluetooth_print_plus: ^2.4.5
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Add permissions for Bluetooth #
We need to add the permission to use Bluetooth and access location:
Android
In the android/app/src/main/AndroidManifest.xml let’s add:
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
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IOS
In the ios/Runner/Info.plist let’s add:
<key>NSBluetoothAlwaysUsageDescription</key>
<string>Need BLE permission</string>
<key>NSBluetoothPeripheralUsageDescription</key>
<string>Need BLE permission</string>
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import #
import 'package:bluetooth_print_plus/bluetooth_print_plus.dart';
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BluetoothPrintPlus useful property #
BluetoothPrintPlus.isBlueOn;
BluetoothPrintPlus.isScanning;
BluetoothPrintPlus.isConnected;
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listen #
late StreamSubscription<bool> _isScanningSubscription;
late StreamSubscription<BlueState> _blueStateSubscription;
late StreamSubscription<ConnectState> _connectStateSubscription;
late StreamSubscription<Uint8List> _receivedDataSubscription;
late StreamSubscription<List<BluetoothDevice>> _scanResultsSubscription;
late List<BluetoothDevice> _scanResults;
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- scan results
/// listen scanResults
_scanResultsSubscription = BluetoothPrintPlus.scanResults.listen((event) {
if (mounted) {
setState(() {
_scanResults = event;
});
}
});
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- state
/// listen isScanning
_isScanningSubscription = BluetoothPrintPlus.isScanning.listen((event) {
print('********** isScanning: $event **********');
if (mounted) {
setState(() {});
}
});
/// listen blue state
_blueStateSubscription = BluetoothPrintPlus.blueState.listen((event) {
print('********** blueState change: $event **********');
/// blue state changed, do something...
});
/// listen connect state
_blueStateSubscription = _BluetoothPrintPlus.connectState.listen((event) {
print('********** connectState change: $event **********');
/// connect state changed, do something...
});
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- received Data
_BluetoothPrintPlus.receivedData.listen((data) {
print('********** received data: $data **********');
/// received data, do something...
});
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scan #
// begin scan
await BluetoothPrintPlus.startScan(timeout: Duration(seconds: 10));
// get devices
_scanResultsSubscription = BluetoothPrintPlus.scanResults.listen((event) {
if (mounted) {
setState(() {
_scanResults = event;
});
}
});
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connect #
await BluetoothPrintPlus.connect(_device);
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disconnect #
await BluetoothPrintPlus.disconnect();
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print/write #
final ByteData bytes = await rootBundle.load("assets/dithered-image.png");
/// write tsc command, for example:
final Uint8List image = bytes.buffer.asUint8List();
await tscCommand.cleanCommand();
await tscCommand.size(width: 76, height: 130);
await tscCommand.cls(); // most after size
await tscCommand.image(image: image, x: 50, y: 60);
await tscCommand.print(1);
final cmd = await tscCommand.getCommand();
if (cmd == null) return;
BluetoothPrintPlus.write(cmd);
/// write cpcl command, for example:
await cpclCommand.cleanCommand();
await cpclCommand.size(width: 76 * 8, height: 76 * 8);
await cpclCommand.image(image: image, x: 10, y: 10);
await cpclCommand.print();
final cmd = await cpclCommand.getCommand();
if (cmd == null) return;
BluetoothPrintPlus.write(cmd);
/// write esc command, for example:
await escCommand.cleanCommand();
await escCommand.print();
await escCommand.image(image: image);
await escCommand.print();
final cmd = await escCommand.getCommand();
if (cmd == null) return;
BluetoothPrintPlus.write(cmd);
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Cancel Subscription #
@override
void dispose() {
super.dispose();
_isScanningSubscription.cancel();
_blueStateSubscription.cancel();
_connectStateSubscription.cancel();
_receivedDataSubscription.cancel();
_scanResultsSubscription.cancel();
_scanResults.clear();
_device = null;
}
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Troubleshooting #
error:'State restoration of CBCentralManager is only allowed for applications that have specified the "bluetooth-central" background mode'
info.plist add:
<key>NSBluetoothAlwaysUsageDescription</key>
<string>Allow App use bluetooth?</string>
<key>NSBluetoothPeripheralUsageDescription</key>
<string>Allow App use bluetooth?</string>
<key>UIBackgroundModes</key>
<array>
<string>bluetooth-central</string>
<string>bluetooth-peripheral</string>
</array>
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