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[web-bluetooth] No trigger characteristicvaluechanged method

From: Zhangrui via GitHub <sysbot+gh@w3.org>
Date: Thu, 17 Aug 2017 08:01:13 +0000
To: public-web-bluetooth-log@w3.org
Message-ID: <issues.opened-250860239-1502956868-sysbot+gh@w3.org>
brave2016 has just created a new issue for https://github.com/WebBluetoothCG/web-bluetooth:

== No trigger characteristicvaluechanged method ==
There is no problem with the following code

 let chosenHeartRateService = null;
 

function search(){
	document.getElementById("demo").innerHTML="My First JavaScript";
	let options = {
		optionalServices:['00000000-0000-1000-8000-00805f9b34fb']
	};
	let filters = [];
	
	let  services = document.querySelector('#services').value;
	let  filterName = document.querySelector('#name').value;
	let  Prefix = document.querySelector('#Prefix').value;
	if(services || filterName || Prefix){
    if (filterName) {
    filters.push({name:filterName});
	}
	 if(services){
		 filters.push({services:[services]});
	 }
	 if(Prefix){
		  filters.push({namePrefix: Prefix});
	 }
	 options.filters = filters;
	 
	 
    }else{
     options.acceptAllDevices = true;
    }
  
	navigator.bluetooth.requestDevice(options).then(device => {
		
	return	device.gatt.connect();
	
		       }).then(server => {		
			 return server.getPrimaryService('00000000-0000-1000-8000-00805f9b34fb');
			}).then(service => {
			 chosenHeartRateService = service;
			return Promise.all([
			
				  service.getCharacteristic('00000001-0000-1000-8000-00805f9b34fb').then(w),
				  service.getCharacteristic('00000003-0000-1000-8000-00805f9b34fb').then(read)
			]);
	
             }).catch(error => {
			          document.getElementById("demo").innerHTML=error;
			});
}

function read(characteristic){
  return characteristic.startNotifications()
  .then(char => {
    characteristic.addEventListener('characteristicvaluechanged',
                                   onHeartRateChanged );
  });
	
}
//var tmp_count = 0 ;
function onHeartRateChanged (event) {
     var value = event.target.value;
  	document.getElementById("data").innerHTML="Received"+sensorLocation;
	//tmp_count ++ ;
		//document.getElementById("data").innerHTML=tmp_count;
}



function w(characteristic){
    let resetEnergyExpended = new Uint8Array([34,8,35,7]);
    characteristic.writeValue(resetEnergyExpended);
	document.getElementById("w").innerHTML="write";
}






Please view or discuss this issue at https://github.com/WebBluetoothCG/web-bluetooth/issues/372 using your GitHub account
Received on Thursday, 17 August 2017 08:01:13 UTC

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