##<platinum-bluetooth-characteristic>
The <platinum-bluetooth-characteristic> element allows you to read
and write characteristics on nearby bluetooth devices thanks to the
young Web Bluetooth API. It is currently partially implemented
behind the experimental flag chrome://flags/#enable-web-bluetooth. It
is also now available in Chrome 53 as an origin trial for Chrome
OS, Android M, and Mac.
<platinum-bluetooth-characteristic> needs to be a child of a
<platinum-bluetooth-service> element.
For instance, here's how to read battery level from a nearby bluetooth device advertising Battery service:
<platinum-bluetooth-device services-filter='["battery_service"]'>
<platinum-bluetooth-service service='battery_service'>
<platinum-bluetooth-characteristic characteristic='battery_level'>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var batteryLevel = document.querySelector('platinum-bluetooth-characteristic');
button.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
return batteryLevel.read().then(function(value) {
console.log('Battery Level is ' + value.getUint8(0) + '%');
});
})
.catch(function(error) { });
});Here's another example on how to reset energy expended on nearby bluetooth device advertising Heart Rate service:
<platinum-bluetooth-device services-filter='["heart_rate"]'>
<platinum-bluetooth-service service='heart_rate'>
<platinum-bluetooth-characteristic characteristic='heart_rate_control_point'>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var heartRateCtrlPoint = document.querySelector('platinum-bluetooth-characteristic');
button.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
// Writing 1 is the signal to reset energy expended.
var resetEnergyExpended = new Uint8Array([1]);
return heartRateCtrlPoint.write(resetEnergyExpended).then(function() {
console.log('Energy expended has been reset');
});
})
.catch(function(error) { });
});It is also possible for <platinum-bluetooth-characteristic> to fill in
a data-bound field in response to a read.
<platinum-bluetooth-device services-filter='["heart_rate"]'>
<platinum-bluetooth-service service='heart_rate'>
<platinum-bluetooth-characteristic characteristic='body_sensor_location'
value={{bodySensorLocation}}>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>
...
<span>{{bodySensorLocation}}</span>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var bodySensorLocation = document.querySelector('platinum-bluetooth-characteristic');
button.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
return bodySensorLocation.read()
})
.catch(function(error) { });
});Starting and stopping notifications on a <platinum-bluetooth-characteristic> is pretty straightforward when taking advantage of the Polymer Change notification protocol. Here's how to get your Heart Rate Measurement for instance:
<platinum-bluetooth-device services-filter='["heart_rate"]'>
<platinum-bluetooth-service service='heart_rate'>
<platinum-bluetooth-characteristic characteristic='heart_rate_measurement'
on-value-changed='parseHeartRate'>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var heartRate = document.querySelector('platinum-bluetooth-characteristic');
startButton.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
return heartRate.startNotifications().catch(function(error) { });
});
});
stopButton.addEventListener('click', function() {
heartRate.stopNotifications().catch(function(error) { });
});
function parseHeartRate(event) {
let value = event.target.value;
// Do something with the DataView Object value...
}You can also use changes in value to drive characteristic writes when
auto-write property is set to true.
<platinum-bluetooth-device services-filter='["heart_rate"]'>
<platinum-bluetooth-service service='heart_rate'>
<platinum-bluetooth-characteristic characteristic='heart_rate_control_point'
auto-write>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var heartRateCtrlPoint = document.querySelector('platinum-bluetooth-characteristic');
button.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
// Writing 1 is the signal to reset energy expended.
heartRateCtrlPoint.value = new Uint8Array([1]);
})
.catch(function(error) { });
});
heartRateCtrlPoint.addEventListener('platinum-bluetooth-auto-write-error',
function(event) {
// Handle error...
});##<platinum-bluetooth-device>
The <platinum-bluetooth-device> element allows you to discover nearby
bluetooth devices thanks to the young Web Bluetooth API. It is
currently partially implemented behind the experimental flag
chrome://flags/#enable-web-bluetooth. It is also now available in
Chrome 53 as an origin trial for Chrome OS, Android M, and Mac.
<platinum-bluetooth-device> is used as a parent element for
<platinum-bluetooth-service> child elements.
For instance, here's how to request a nearby bluetooth device advertising Battery service:
<platinum-bluetooth-device services-filter='["battery_service"]'>
</platinum-bluetooth-device>button.addEventListener('click', function() {
document.querySelector('platinum-bluetooth-device').request()
.then(function(device) { console.log(device.name); })
.catch(function(error) { console.error(error); });
});You can also request a nearby bluetooth device by setting a filter on a name or name Prefix:
<platinum-bluetooth-device name-filter='foobar'>
</platinum-bluetooth-device><platinum-bluetooth-device name-prefix-filter='foo'>
</platinum-bluetooth-device>And you can combine some of the filters as well. Here's how to request a nearby bluetooth device advertising Battery service and whose name is "foobar":
<platinum-bluetooth-device services-filter='["battery_service"]'
name-filter='foobar'>
</platinum-bluetooth-device>If you filter just by name, then you must use optional-services-filter
to get access to any services:
<platinum-bluetooth-device name-filter='foobar'
optional-services-filter='["battery_service"]'>
</platinum-bluetooth-device>Disconnecting manually from a connected bluetooth device is pretty straightforward:
disconnectButton.addEventListener('click', function() {
document.querySelector('platinum-bluetooth-device').disconnect();
});##<platinum-bluetooth-service>
The <platinum-bluetooth-service> element is used in conjuction with
the <platinum-bluetooth-characteristic> element to read and write
characteristics on nearby bluetooth devices thanks to the young Web
Bluetooth API. It is currently partially implemented
behind the experimental flag
chrome://flags/#enable-web-bluetooth. It is also now
available in Chrome 53 as an origin trial for Chrome OS,
Android M, and Mac.
<platinum-bluetooth-service> needs to be a child of a
<platinum-bluetooth-device> element.
For instance, here's how to read battery level from a nearby bluetooth device advertising Battery service:
<platinum-bluetooth-device services-filter='["battery_service"]'>
<platinum-bluetooth-service service='battery_service'>
<platinum-bluetooth-characteristic characteristic='battery_level'>
</platinum-bluetooth-characteristic>
</platinum-bluetooth-service>
</platinum-bluetooth-device>var bluetoothDevice = document.querySelector('platinum-bluetooth-device');
var batteryLevel = document.querySelector('platinum-bluetooth-characteristic');
button.addEventListener('click', function() {
bluetoothDevice.request().then(function() {
return batteryLevel.read().then(function(value) {
console.log('Battery Level is ' + value.getUint8(0) + '%');
});
})
.catch(function(error) { });
});