對於藍牙有寫入數據的話，需要時低功耗的藍牙。向低功耗藍牙設備特征值中寫入二進制數據。注意：必須設備的特征值支持 write 才可以成功調用。
https://developers.weixin.qq.com/miniprogram/dev/api/device/bluetooth-ble/wx.writeBLECharacteristicValue.html
先搜索藍牙設備
wxml
<button class="btn" type="primary" bindtap="startSearch" loading='{{isScanning}}'> 開始搜索 </button>
<view wx:for="{{list}}" wx:for-item="item" data-title="{{item.deviceId}}" data-name="{{item.name}}" data-advertisData="{{item.advertisServiceUUIDs}}" wx:key="{{item.deviceId}}" bindtap="bindViewTap">
<view class="item">
<div class="deviceId block">{{item.deviceId}}</div>
<div class="name block">{{item.name}}</div>
</view>
</view>
js
app.BLEInformation.platform = getApp().getPlatform()
data: {
list: [],
services: [],
serviceId: 0,
writeCharacter: false,
readCharacter: false,
notifyCharacter: false,
isScanning:false
},
startSearch: function () {
var that = this
wx.openBluetoothAdapter({
success: function (res) {
wx.getBluetoothAdapterState({
success: function (res) {
if (res.available) {
if (res.discovering) {
wx.stopBluetoothDevicesDiscovery({
success: function (res) {
console.log(res)
}
})
}
that.checkPemission()
} else {
wx.showModal({
title: '提示',
content: '本機藍牙不可用',
})
}
},
})
}, fail: function () {
wx.showModal({
title: '提示',
content: '藍牙初始化失敗，請打開藍牙',
})
}
})
},
checkPemission: function () { //android 6.0以上需授權地理位置權限
var that = this
var platform = app.BLEInformation.platform
if (platform == "ios") {
app.globalData.platform = "ios"
that.getBluetoothDevices()
} else if (platform == "android") {
app.globalData.platform = "android"
console.log(app.getSystem().substring(app.getSystem().length - (app.getSystem().length - 8), app.getSystem().length - (app.getSystem().length - 8) + 1))
if (app.getSystem().substring(app.getSystem().length - (app.getSystem().length - 8), app.getSystem().length - (app.getSystem().length - 8) + 1) > 5) {
wx.getSetting({
success: function (res) {
console.log(res)
if (!res.authSetting['scope.userLocation']) {
wx.authorize({
scope: 'scope.userLocation',
complete: function (res) {
that.getBluetoothDevices()
}
})
} else {
that.getBluetoothDevices()
}
}
})
}
}
},
getBluetoothDevices: function () { //獲取藍牙設備信息
var that = this
console.log("start search")
wx.showLoading({
title: '正在加載',
})
that.setData({
isScanning:true
})
wx.startBluetoothDevicesDiscovery({
success: function (res) {
console.log(res)
setTimeout(function () {
wx.getBluetoothDevices({
success: function (res) {
var devices = []
var num = 0
for (var i = 0; i < res.devices.length; ++i) {
if (res.devices[i].name != "未知設備") {
devices[num] = res.devices[i]
num++
}
}
that.setData({
list: devices,
isScanning:false
})
wx.hideLoading()
wx.stopPullDownRefresh()
},
})
}, 3000)
},
})
},
bindViewTap: function (e) {
var that = this
wx.stopBluetoothDevicesDiscovery({
success: function (res) { console.log(res) },
})
that.setData({
serviceId: 0,
writeCharacter: false,
readCharacter: false,
notifyCharacter: false
})
console.log(e.currentTarget.dataset.title)
wx.showLoading({
title: '正在連接',
})
wx.createBLEConnection({
deviceId: e.currentTarget.dataset.title,
success: function (res) {
console.log(res)
app.BLEInformation.deviceId = e.currentTarget.dataset.title
that.getSeviceId()
}, fail: function (e) {
wx.showModal({
title: '提示',
content: '連接失敗',
})
console.log(e)
wx.hideLoading()
}, complete: function (e) {
console.log(e)
}
})
},
getSeviceId: function () {
var that = this
var platform = app.BLEInformation.platform
console.log(app.BLEInformation.deviceId)
wx.getBLEDeviceServices({
deviceId: app.BLEInformation.deviceId,
success: function (res) {
console.log(res)
that.setData({
services: res.services
})
that.getCharacteristics()
}, fail: function (e) {
console.log(e)
}, complete: function (e) {
console.log(e)
}
})
},
getCharacteristics: function () {
var that = this
var list = that.data.services
var num = that.data.serviceId
var write = that.data.writeCharacter
var read = that.data.readCharacter
var notify = that.data.notifyCharacter
wx.getBLEDeviceCharacteristics({
deviceId: app.BLEInformation.deviceId,
serviceId: list[num].uuid,
success: function (res) {
console.log(res)
for (var i = 0; i < res.characteristics.length; ++i) {
var properties = res.characteristics[i].properties
var item = res.characteristics[i].uuid
if (!notify) {
if (properties.notify) {
app.BLEInformation.notifyCharaterId = item
app.BLEInformation.notifyServiceId = list[num].uuid
notify = true
}
}
if (!write) {
if (properties.write) {
app.BLEInformation.writeCharaterId = item
app.BLEInformation.writeServiceId = list[num].uuid
write = true
}
}
if (!read) {
if (properties.read) {
app.BLEInformation.readCharaterId = item
app.BLEInformation.readServiceId = list[num].uuid
read = true
}
}
}
if (!write || !notify || !read) {
num++
that.setData({
writeCharacter: write,
readCharacter: read,
notifyCharacter: notify,
serviceId: num
})
if(num == list.length){
wx.showModal({
title: '提示',
content: '找不到該讀寫的特征值',
})
}else{
that.getCharacteristics()
}
} else {
that.openControl()
}
}, fail: function (e) {
console.log(e)
}, complete: function (e) {
console.log("write:"+app.BLEInformation.writeCharaterId)
console.log("read:"+app.BLEInformation.readCharaterId)
console.log("notify:"+app.BLEInformation.notifyCharaterId)
}
})
},
openControl: function () {
wx.navigateTo({
url: '../startPrint/startPrint',
})
},
然后打印
下面就是startPrint的代碼
wxml
<view class="body">
<textarea class="input" bindinput="inputEvent" />
<button type="primary" bindtap="sendData">發送(票據可使用)</button>
<button type='primary' bindtap='labelTest' loading='{{isLabelSend}}' disabled='{{isLabelSend}}'>標簽測試</button>
</view>
下面是 js 的代碼，首先是設置變量
data: {
sendContent: "",
looptime: 0,
currentTime: 1,
lastData: 0,
oneTimeData: 0,
returnResult: "returnResult",
canvasWidth: 80,
canvasHeight: 80,
buffSize: [],
buffIndex: 0,
printNum: [],
printNumIndex: 0,
printerNum: 1,
currentPrint: 1,
isReceiptSend: false,
isLabelSend: false
},
command.setCls() ，需要設置這個，不然內容和上一次重復
onLoad: function(options) {
var that = this;
wx.notifyBLECharacteristicValueChange({
deviceId: app.BLEInformation.deviceId,
serviceId: app.BLEInformation.notifyServiceId,
characteristicId: app.BLEInformation.notifyCharaterId,
state: true,
success: function(res) {
wx.onBLECharacteristicValueChange(function(r) {
console.log(`characteristic ${r.characteristicId} has changed, now is ${r}`)
})
},
fail: function(e) {
console.log('fail', e)
},
complete: function(e) {
console.log('complete', e)
}
})
},
inputEvent: function(e) {
this.setData({
sendContent: e.detail.value
})
console.log('sendContent: ', this.sendContent)
},
sendData: function() {
var data = this.data.sendContent + "\n"
var that = this;
var command = tsc.jpPrinter.createNew()
command.setGap(0)
command.setCls()
command.setText(60, 90, "TSS24.BF2", 1, 1, data)
command.setPagePrint()
that.prepareSend(command.getData())
},
labelTest: function() {
var that = this;
var canvasWidth = that.data.canvasWidth
var canvasHeight = that.data.canvasHeight
var command = tsc.jpPrinter.createNew()
command.setSize(48, 40)
command.setGap(0)
command.setCls() //需要設置這個，不然內容和上一次重復
command.setQR(1, 120, "L", 5, "A", "airenao.com")
command.setText(60, 90, "TSS24.BF2", 1, 1, "成都愛熱鬧")
command.setText(170, 50, "TSS24.BF2", 1, 1, "小程序測試")
command.setText(170, 90, "TSS24.BF2", 1, 1, "測試數字12345678")
command.setText(170, 120, "TSS24.BF2", 1, 1, "測試英文abcdefg")
command.setText(170, 150, "TSS24.BF2", 1, 1, "測試符號/*-+!@#$")
wx.canvasGetImageData({
canvasId: 'edit_area_canvas',
x: 0,
y: 0,
width: canvasWidth,
height: canvasHeight,
success: function(res) {
command.setBitmap(60, 0, 0, res)
},
complete: function() {
command.setPagePrint()
that.setData({
isLabelSend: true
})
that.prepareSend(command.getData())
}
})
},
准備發送內容, printNum 這個是需要打印多少份，buff 是每次打印多少字節數
prepareSend: function(buff) {
console.log('buff', buff)
var that = this
var time = that.data.oneTimeData
var looptime = parseInt(buff.length / time);
var lastData = parseInt(buff.length % time);
console.log(looptime + "---" + lastData)
that.setData({
looptime: looptime + 1,
lastData: lastData,
currentTime: 1,
})
that.Send(buff)
},
queryStatus: function() { //查詢打印機狀態
var command = esc.jpPrinter.Query();
command.getRealtimeStatusTransmission(1);
this.setData({
returnResult: "查詢成功"
})
},
Send: function(buff) { //分包發送
var that = this
var currentTime = that.data.currentTime
var loopTime = that.data.looptime
var lastData = that.data.lastData
var onTimeData = that.data.oneTimeData
var printNum = that.data.printerNum //打印多少份
var currentPrint = that.data.currentPrint
var buf
var dataView
if (currentTime < loopTime) {
buf = new ArrayBuffer(onTimeData)
dataView = new DataView(buf)
for (var i = 0; i < onTimeData; ++i) {
dataView.setUint8(i, buff[(currentTime - 1) * onTimeData + i])
}
} else {
buf = new ArrayBuffer(lastData)
dataView = new DataView(buf)
for (var i = 0; i < lastData; ++i) {
dataView.setUint8(i, buff[(currentTime - 1) * onTimeData + i])
}
}
console.log("第" + currentTime + "次發送數據大小為：" + buf.byteLength)
wx.writeBLECharacteristicValue({
deviceId: app.BLEInformation.deviceId,
serviceId: app.BLEInformation.writeServiceId,
characteristicId: app.BLEInformation.writeCharaterId,
value: buf,
success: function(res) {
console.log('寫入成功', res)
},
fail: function(e) {
console.fail('寫入失敗', e)
},
complete: function() {
currentTime++
if (currentTime <= loopTime) {
that.setData({
currentTime: currentTime
})
that.Send(buff)
} else {
wx.showToast({
title: '已打印第' + currentPrint + '張',
})
if (currentPrint == printNum) {
that.setData({
looptime: 0,
lastData: 0,
currentTime: 1,
isReceiptSend: false,
isLabelSend: false,
currentPrint: 1
})
} else {
currentPrint++
that.setData({
currentPrint: currentPrint,
currentTime: 1,
})
console.log("開始打印")
that.Send(buff)
}
}
}
})
},
最后的成品樣子
