我想通过程序启用/禁用蓝牙。我有以下代码。
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
但是这段代码在SDK 1.5中无法工作。我该如何使它工作？
//Disable bluetooth
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.disable();
}
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
在 Android API 33+ (13+) 中，此方法已被弃用，并且不再可能在没有用户同意的情况下启用/禁用蓝牙。根据文档，您应该改用ACTION_REQUEST_ENABLE。
android.permission.BLUETOOTH_CONNECT。否则它会授予权限但不会禁用。 - Luis A. Florit以下是一种更为健壮的方法，还能处理enable()\disable()方法的返回值：
public static boolean setBluetooth(boolean enable) {
BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
boolean isEnabled = bluetoothAdapter.isEnabled();
if (enable && !isEnabled) {
return bluetoothAdapter.enable();
}
else if(!enable && isEnabled) {
return bluetoothAdapter.disable();
}
// No need to change bluetooth state
return true;
}
请将以下权限添加到您的清单文件中：
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
但请记住以下重要点：
这是一个异步调用：它会立即返回，客户端应该监听 ACTION_STATE_CHANGED 以便在适配器状态发生变化时得到通知。如果此调用返回 true，则适配器状态将立即从 STATE_OFF 转换为 STATE_TURNING_ON，稍后转换为 STATE_OFF 或 STATE_ON。如果此调用返回 false，则会出现立即阻止适配器开启的问题，例如飞行模式或适配器已经打开。
更新：
好的，那么如何实现蓝牙监听器？：
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (action.equals(BluetoothAdapter.ACTION_STATE_CHANGED)) {
final int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE,
BluetoothAdapter.ERROR);
switch (state) {
case BluetoothAdapter.STATE_OFF:
// Bluetooth has been turned off;
break;
case BluetoothAdapter.STATE_TURNING_OFF:
// Bluetooth is turning off;
break;
case BluetoothAdapter.STATE_ON:
// Bluetooth is on
break;
case BluetoothAdapter.STATE_TURNING_ON:
// Bluetooth is turning on
break;
}
}
}
};
如何在您的Activity类中注册/取消注册接收器？
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ...
// Register for broadcasts on BluetoothAdapter state change
IntentFilter filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
registerReceiver(mReceiver, filter);
}
@Override
public void onStop() {
super.onStop();
// ...
// Unregister broadcast listeners
unregisterReceiver(mReceiver);
}
BLUETOOTH_ADMIN权限，它就可以工作，但如果没有，则需要使用startActivityForResult(enableBtIntent, 0);来启用蓝牙。 - Majid GolshadiAndroid的BluetoothAdapter文档显示它自API Level 5就可用了。API Level 5是指Android 2.0。
你可以尝试使用蓝牙API的后移版本（我个人没有尝试过）：http://code.google.com/p/backport-android-bluetooth/
要启用蓝牙，您可以使用以下任一函数：
public void enableBT(){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()){
Intent intentBtEnabled = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
// The REQUEST_ENABLE_BT constant passed to startActivityForResult() is a locally defined integer (which must be greater than 0), that the system passes back to you in your onActivityResult()
// implementation as the requestCode parameter.
int REQUEST_ENABLE_BT = 1;
startActivityForResult(intentBtEnabled, REQUEST_ENABLE_BT);
}
}
第二个函数是：
public void enableBT(){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()){
mBluetoothAdapter.enable();
}
}
两个函数的区别在于，第一个函数会让应用程序向用户请求权限来打开或拒绝蓝牙。而第二个函数会直接打开蓝牙。
要禁用蓝牙，请使用以下函数：
public void disableBT(){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter.isEnabled()){
mBluetoothAdapter.disable();
}
}
注意/第一个函数仅需要在AndroidManifest.xml文件中定义以下权限：
<uses-permission android:name="android.permission.BLUETOOTH"/>
第二和第三个函数需要以下权限：
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
Prijin的解决方案对我非常有效。公平地说，还需要两个额外的权限：
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
class ActivityResultHandler(
private val registry: ActivityResultRegistry
) {
private val handlers = mutableListOf<ActivityResultLauncher<*>>()
fun unregisterHandlers() {
handlers.forEach {
it.unregister()
}
}
suspend fun requestLocationPermission(): Boolean {
return suspendCoroutine<Boolean> { continuation ->
val launcher = registry.register(
LOCATION_PERMISSION_REQUEST,
// lifecycleOwner,
ActivityResultContracts.RequestPermission()
) {
continuation.resumeWith(Result.success(it))
}
handlers.add(launcher)
launcher.launch(Manifest.permission.ACCESS_FINE_LOCATION)
}
}
suspend fun requestBluetoothActivation(): Boolean {
return suspendCoroutine<Boolean> { continuation ->
val enableBtIntent = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
val launcher = registry.register(
BLUETOOTH_ON_REQUEST,
// lifecycleOwner,
ActivityResultContracts.StartActivityForResult()
) { result ->
continuation.resume(
result.resultCode == Activity.RESULT_OK
)
}
handlers.add(launcher)
launcher.launch(enableBtIntent)
}
}
fun checkLocationPermission(context: Context): Boolean {
return ContextCompat.checkSelfPermission(
context,
Manifest.permission.ACCESS_FINE_LOCATION
) == PackageManager.PERMISSION_GRANTED
}
private suspend fun requestLocationActivation(
intentSenderRequest: IntentSenderRequest,
): Boolean {
return suspendCoroutine { continuation ->
val launcher = registry.register(
LOCATION_ACTIVATION_REQUEST,
// lifecycleOwner,
ActivityResultContracts.StartIntentSenderForResult()
) {
continuation.resume(it.resultCode == Activity.RESULT_OK)
}
handlers.add(launcher)
launcher.launch(intentSenderRequest)
}
}
suspend fun enableLocation(context: Context): Boolean =
suspendCoroutine { continuation ->
val locationSettingsRequest = LocationSettingsRequest.Builder()
// .setNeedBle(true)
.addLocationRequest(
LocationRequest.create().apply {
priority = LocationRequest.PRIORITY_HIGH_ACCURACY
}
)
.build()
val client: SettingsClient = LocationServices.getSettingsClient(context)
val task: Task<LocationSettingsResponse> =
client.checkLocationSettings(locationSettingsRequest)
task.addOnSuccessListener {
continuation.resume(true)
}
task.addOnFailureListener { exception ->
if (exception is ResolvableApiException &&
exception.statusCode == LocationSettingsStatusCodes.RESOLUTION_REQUIRED
) {
val intentSenderRequest =
IntentSenderRequest.Builder(exception.resolution).build()
CoroutineScope(continuation.context).launch {
val result = requestLocationActivation(intentSenderRequest)
continuation.resume(result)
}
} else {
continuation.resume(false)
}
}
}
companion object {
private const val LOCATION_PERMISSION_REQUEST = "LOCATION_REQUEST"
private const val BLUETOOTH_ON_REQUEST = "LOCATION_REQUEST"
private const val LOCATION_ACTIVATION_REQUEST = "LOCATION_REQUEST"
}
}
使用方式如下：
// make sure you extend AppCompatActivity
class MainActivity : AppCompatActivity() {
private val permissionRequests = ActivityResultHandler(activityResultRegistry)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// use viewmodels and fragments instead of GlobalScope
GlobalScope.launch {
// turn on bluetooth
permissionRequests.requestBluetoothActivation()
// to be able to scan for devices you also need location permission
// also show pop up to let users know why you need location
// https://support.google.com/googleplay/android-developer/answer/9799150?hl=en
permissionRequests.requestLocationPermission()
// also you need navigation to be enabled
permissionRequests.enableLocation(this@MainActivity)
}
}
override fun onDestroy() {
super.onDestroy()
permissionRequests.unregisterHandlers()
}
}
Gradle中的协程依赖
implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.4.2'
同时在清单文件中添加以下权限
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission-sdk-23 android:name="android.permission.ACCESS_COARSE_LOCATION" />
AppCompatActivity 吗？activityResultRegistry 存在于 ComponentActivity 中，而这个类又被 FragmentActivity 继承，最终被 AppCompatActivity 继承...也许你可以在 Github 上搜索一下？至少会有一个项目会使用它。 - George Shalvashvili针对Android 12进行更新：
AndroidManifest.xml -
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT"/>
当您请求存储或其他“提示”项目的权限时，必须像请求权限 BLUETOOTH_CONNECT 一样执行标准权限请求。
用法（Kotlin）-
val bluetoothAdapter = (getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager).adapter
if (bluetoothAdapter.isEnabled)
bluetoothAdapter.disable()
针对Android 12及以上的版本，在获取当前状态或切换蓝牙的情况下不再需要BLUETOOTH和BLUETOOTH_ADMIN权限，除非要针对更低的API版本。
我在我的应用启动时使用以下代码来禁用蓝牙，它可以正常工作。不确定这是否是正确实现的方法，因为谷歌建议不要在没有显式用户操作关闭蓝牙的情况下使用"bluetooth.disable();"。
BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();
bluetooth.disable();
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
启用蓝牙使用此功能
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.enable();
}else{Toast.makeText(getApplicationContext(), "Bluetooth Al-Ready Enable", Toast.LENGTH_LONG).show();}
禁用蓝牙使用此功能
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.disable();
}
试试这个：
//this method to check bluetooth is enable or not: true if enable, false is not enable
public static boolean isBluetoothEnabled()
{
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
// Bluetooth is not enable :)
return false;
}
else{
return true;
}
}
//method to enable bluetooth
public static void enableBluetooth(){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.enable();
}
}
//method to disable bluetooth
public static void disableBluetooth(){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.disable();
}
}
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>