【发布时间】:2023-01-16 13:47:59
【问题描述】:
我不再能够确定从我的任何蓝牙设备按下了哪个按钮。
GetParcelableExtra 在 MEDIA_BUTTON 意图回调中为 KEY_EVENT 返回 null。
此方法工作了几个月,但突然开始在 GetParcableExtra 上返回 null。
如何从 xamarin 中的后台服务获取蓝牙按钮事件?
namespace foo
{
[Service]
class BackgroundService : Service
{
[return: GeneratedEnum]
public override StartCommandResult OnStartCommand(Intent intent, [GeneratedEnum] StartCommandFlags flags, int startId)
{
registerMediaButtons();
return StartCommandResult.Sticky;
}
private void registerMediaButtons()
{
var am = (AudioManager)this.GetSystemService(AudioService);
var componentName = new ComponentName(PackageName, new MyMediaButtonBroadcastReceiver().ComponentName);
#pragma warning disable CS0618 // Type or member is obsolete
am.UnregisterMediaButtonEventReceiver(componentName);
am.RegisterMediaButtonEventReceiver(componentName);
#pragma warning restore CS0618 // Type or member is obsolete
}
[BroadcastReceiver]
[IntentFilter(new[] { Intent.ActionMediaButton, Intent.ActionHeadsetPlug, AudioManager.ActionAudioBecomingNoisy })]
public class MyMediaButtonBroadcastReceiver : BroadcastReceiver
{
public string ComponentName { get { return Class.Name; } }
public override void OnReceive(Context context, Intent intent)
{
if (intent.Action == Intent.ActionMediaButton)
{
var keyEvent = (KeyEvent)intent.GetParcelableExtra(Intent.ExtraKeyEvent);
if (keyEvent == null)// always null now
return;
if (keyEvent.KeyCode == Keycode.Headsethook)
{
if (keyEvent.Action == KeyEventActions.Down)
{
}
}
}
}
}
}
}
【问题讨论】:
标签: java c# android xamarin android-intent