Android 为什么我的RxJava设置阻止我的UI线程?使用BluetoothAdapter.scan回调
我正在努力寻找阻止我的UI线程的特定操作,我尝试了几个调度程序操作符,但我不确定如何使其工作 我有一个带有按钮的用户界面,单击该按钮将启动蓝牙扫描,并使用类似日志的字符串更新文本视图(它显示了当前正在发生的事情) 以下是我的主要活动:Android 为什么我的RxJava设置阻止我的UI线程?使用BluetoothAdapter.scan回调,android,kotlin,rx-java,android-bluetooth,rx-java2,Android,Kotlin,Rx Java,Android Bluetooth,Rx Java2,我正在努力寻找阻止我的UI线程的特定操作,我尝试了几个调度程序操作符,但我不确定如何使其工作 我有一个带有按钮的用户界面,单击该按钮将启动蓝牙扫描,并使用类似日志的字符串更新文本视图(它显示了当前正在发生的事情) 以下是我的主要活动: lateinit var disposable: Disposable val textDataService = TextDataService() override fun onCreate(savedInstanceState: Bundle?) {
lateinit var disposable: Disposable
val textDataService = TextDataService()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_scan_test)
buttonScanTestStart.setOnClickListener {
if (isBluetoothEnabled()) {
textViewLog.text = ""
buttonScanTestStop.visibility = View.VISIBLE
buttonExportScanTestRaportSummary.visibility = View.GONE
buttonExportScanTestRaportFull.visibility = View.GONE
buttonScanTestStart.visibility = View.GONE
disposable=
Scanner()
.discoverSingleDevice(this, " ", textViewLog)
.doOnError {
setText("General error: ${it.message ?: it::class.java}", textViewLog)
setLogText("General error: ${it.message ?: it::class.java}")
}
.repeat(1)
.doOnComplete {
buttonScanTestStop.visibility = View.GONE
}
.doOnDispose {
log("TEST DISPOSED")
}
.subscribe()
} else {
Toast.makeText(this, "Please, enable bluetooth to start test.", Toast.LENGTH_SHORT).show()
}
}
buttonScanTestStop.setOnClickListener {
disposable.dispose()
buttonScanTestStop.visibility = View.GONE
buttonScanTestStart.visibility = View.VISIBLE
buttonExportScanTestRaportSummary.visibility = View.VISIBLE
buttonExportScanTestRaportFull.visibility = View.VISIBLE
textDataService.generateScanGeneralStatisticsLogText(textViewLog)
}
以下是Scanner类:
class Scanner {
private fun scan(context: Context, textView: TextView) = Observable.create<ScannedItem> { emitter ->
val bluetoothAdapter = context.getBluetoothAdapter()
if (bluetoothAdapter.isEnabled) {
val scanCallback = BluetoothAdapter.LeScanCallback { bluetoothDevice, rssi, _ ->
if(bluetoothDevice.name == null){
bluetoothRawLog("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}")
scannedOtherDevices.add(bluetoothDevice.address)
}
else{
if(!scannedDevices.contains(bluetoothDevice.name)){
setText("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}\n", textView)
setLogText("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}\n")
}
scannedDevices.add(bluetoothDevice.name)
}
bluetoothRawLog("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi")
bluetoothDevice.name?.let {
emitter.onNext(ScannedItem(it, bluetoothDevice.address))
}
}
emitter.setCancellable { bluetoothAdapter.stopLeScan(scanCallback) }
bluetoothAdapter.startLeScan(scanCallback)
} else
emitter.onError(IllegalStateException("Bluetooth turned off"))
}
.doOnNext { log("Scanned -> $it") }
.timeout(12, TimeUnit.SECONDS)
.observeOn(AndroidSchedulers.mainThread())
.doOnError { if (it is TimeoutException) setLogText("Scanner -> no named devices for 12 seconds: resetting...") }
.retry { t -> t is TimeoutException }
fun discoverSingleDevice(context: Context, searchName: String, textView: TextView): Observable<ScannedItem> = scan(context, textView)
.filter { it.name.contains(searchName) }
.take(1)
private fun scan(context: Context, textView: TextView) = Observable.create<ScannedItem> { emitter ->
val bluetoothAdapter = context.getBluetoothAdapter()
if (bluetoothAdapter.isEnabled) {
val scanCallback = BluetoothAdapter.LeScanCallback { bluetoothDevice, rssi, _ ->
Log.v("BluetoothThread", "Running on: " + Thread.currentThread().name)
///the rest of the code
这也是我的布局:
<?xml version="1.0" encoding="utf-8"?>
然而,这没有帮助,也不是那么简单。再一次,我尝试了其他操作员的一些方法。
请针对我的情况-我提供了代码。
这就像扫描2分钟后,应用程序相当冻结。在日志中,我/编舞:跳过了54帧!应用程序可能在其主线程上做了太多工作
更新2:
正如PhoenixWang所建议的,我已经登录以检查BluetoothAdapter运行的线程。我在Scanner类中的scan方法中这样做:
class Scanner {
private fun scan(context: Context, textView: TextView) = Observable.create<ScannedItem> { emitter ->
val bluetoothAdapter = context.getBluetoothAdapter()
if (bluetoothAdapter.isEnabled) {
val scanCallback = BluetoothAdapter.LeScanCallback { bluetoothDevice, rssi, _ ->
if(bluetoothDevice.name == null){
bluetoothRawLog("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}")
scannedOtherDevices.add(bluetoothDevice.address)
}
else{
if(!scannedDevices.contains(bluetoothDevice.name)){
setText("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}\n", textView)
setLogText("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi | time: = ${getCurrentTime()}\n")
}
scannedDevices.add(bluetoothDevice.name)
}
bluetoothRawLog("Scanned Item -> ${bluetoothDevice.logText()} | rssi = $rssi")
bluetoothDevice.name?.let {
emitter.onNext(ScannedItem(it, bluetoothDevice.address))
}
}
emitter.setCancellable { bluetoothAdapter.stopLeScan(scanCallback) }
bluetoothAdapter.startLeScan(scanCallback)
} else
emitter.onError(IllegalStateException("Bluetooth turned off"))
}
.doOnNext { log("Scanned -> $it") }
.timeout(12, TimeUnit.SECONDS)
.observeOn(AndroidSchedulers.mainThread())
.doOnError { if (it is TimeoutException) setLogText("Scanner -> no named devices for 12 seconds: resetting...") }
.retry { t -> t is TimeoutException }
fun discoverSingleDevice(context: Context, searchName: String, textView: TextView): Observable<ScannedItem> = scan(context, textView)
.filter { it.name.contains(searchName) }
.take(1)
private fun scan(context: Context, textView: TextView) = Observable.create<ScannedItem> { emitter ->
val bluetoothAdapter = context.getBluetoothAdapter()
if (bluetoothAdapter.isEnabled) {
val scanCallback = BluetoothAdapter.LeScanCallback { bluetoothDevice, rssi, _ ->
Log.v("BluetoothThread", "Running on: " + Thread.currentThread().name)
///the rest of the code
正如Phoenix Wang所建议的,BluetoothAdapter.LeScanCallback由于其实现而在主线程中运行。Observable/RxJava无法更改它。
那么如何解决我的问题呢?RxJava默认是同步的。在您的例子中,它在调用者线程上运行,调用者线程是Android的主线程 您必须指定希望订阅发生的线程
Observable.fromCallable(whatever())
.subscribeOn(Schedulers.newThread()).subscribe()
阅读更多
添加.subscribeOn(Schedulers.io())以及.observeOn(AndroidSchedulers.mainThread()),如上文所述。试试这个。应该有用。更清楚。我回答了,但不能解决你的问题。 您的代码:
Observable.fromCallable{ bluetoothAdapter.startLeScan(scanCallback)}.subscribeOn(Schedulers.newThread()).subscribe().
意味着您的bluetoothAdapter.startedScan(scanCallback)
在新线程中运行。但不是bluetoothAdapter给你回电话的方式
所以在你的StarteScan的实现中。它可以启动一个新线程,也可以在其他线程中运行,这取决于它的实现
与您的Observable.create相同(//您的东西)
它们保证在指定的计划程序上运行。但它也可以在其中启动一个新线程。这就是为什么我在评论中提到检查BluetoothAdapter的实现
更新
更清楚地说,BluetoothAdapter的一个示例实现可以阻止您的UI线程
class BluetoothAdapter {
fun startLeScan(callback: LeScanCallback) {
val handler = Handler(Looper.getMainLooper())
handler.post {
// here you back to your UI Thread.
callback.onSuccess(1)
}
}
interface LeScanCallback {
fun onSuccess(result: Int)
}
}
因此,如果您的BluetoothAdapter实现将线程更改回UI线程。你最终会阻止你的UI线程,不管你的可观察线程是什么。这就是我的意思检查BluetoothAdapter的实现当然我已经尝试过了。如果你自己检查我的代码会更好,也许你会发现什么是错误的嘿,我也尝试过你的解决方案,但我想它不是那么简单。也许你可以检查一下我的代码,看看有什么问题?这就像扫描2分钟后,应用程序相当冻结。在日志中,我/编舞:跳过了54帧!应用程序可能在其主线程上做了太多工作。请在BluetoothAdapter中添加一些日志。类似于'Thread.currentThread().name',以指示您当前的操作线程。我得到:V/BluetoothThread:正在运行:main@PhoenixWang我将其记录在BluetoothAdapter.LeScanCallback{bluetoothDevice,rssi,->log,v(“BluetoothThread”,“running on:”+Thread.currentThread().name)中。那么如何解决呢?@PhoenixWang,请检查我的更新是否有意义。BluetoothAdapter.LeScanCallback因其实现而在主线程中运行。Observable/RxJava无法更改它。您最好检查
BluetoothAdapter.StarteScan(scanCallback)
的实现解决了这个问题是的,我尝试过这个,但实际上没有帮助。你能帮我实现吗?@okset抱歉,我不能。你应该检查你的BluetoothAdapter中的代码。可能有类似于runOnUiThread()
,handler.post()的东西
,或AsyncTask
s将这些普通网关返回到您的Ui线程。或者您可以只发布BluetoothAdapter的所有代码,而不是your或Observable。最后一句话是什么意思?您能举个例子吗?我得到的BluetoothAdapter是这样的:有趣的上下文。getBluetoothAdapter():BluetoothAdapter=(getSystemService(Context.BLUETOOTH_服务)作为BluetoothManager)。adapter@okset这可能是Android蓝牙本身的问题。RxJava无法帮助您解决这一问题。
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
Observable.fromCallable{ bluetoothAdapter.startLeScan(scanCallback)}.subscribeOn(Schedulers.newThread()).subscribe().
class BluetoothAdapter {
fun startLeScan(callback: LeScanCallback) {
val handler = Handler(Looper.getMainLooper())
handler.post {
// here you back to your UI Thread.
callback.onSuccess(1)
}
}
interface LeScanCallback {
fun onSuccess(result: Int)
}
}