From b2355940e3e697deeecd1b6511cd5094f9dc553a Mon Sep 17 00:00:00 2001 From: Phil Burk Date: Wed, 5 Aug 2015 23:32:54 -0700 Subject: [PATCH] MidiService: update listener with current status when registered This will give an app an opportunity to learn whether an input port is busy before the user tries to connect and then fails. Bug: 22825043 Change-Id: Ifede60f166dfe66ea15453044fce06f4a8452b18 Signed-off-by: Phil Burk --- media/java/android/media/midi/MidiManager.java | 7 +++++++ .../java/com/android/server/midi/MidiService.java | 21 +++++++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/media/java/android/media/midi/MidiManager.java b/media/java/android/media/midi/MidiManager.java index e72bdb446a65..266b0d97cb53 100644 --- a/media/java/android/media/midi/MidiManager.java +++ b/media/java/android/media/midi/MidiManager.java @@ -169,6 +169,13 @@ public final class MidiManager { /** * Registers a callback to receive notifications when MIDI devices are added and removed. * + * The {@link DeviceCallback#onDeviceStatusChanged} method will be called immediately + * for any devices that have open ports. This allows applications to know which input + * ports are already in use and, therefore, unavailable. + * + * Applications should call {@link #getDevices} before registering the callback + * to get a list of devices already added. + * * @param callback a {@link DeviceCallback} for MIDI device notifications * @param handler The {@link android.os.Handler Handler} that will be used for delivering the * device notifications. If handler is null, then the thread used for the diff --git a/services/midi/java/com/android/server/midi/MidiService.java b/services/midi/java/com/android/server/midi/MidiService.java index 3ecfd5509468..701e07fc2284 100644 --- a/services/midi/java/com/android/server/midi/MidiService.java +++ b/services/midi/java/com/android/server/midi/MidiService.java @@ -575,6 +575,8 @@ public class MidiService extends IMidiManager.Stub { Client client = getClient(token); if (client == null) return; client.addListener(listener); + // Let listener know whether any ports are already busy. + updateStickyDeviceStatus(client.mUid, listener); } @Override @@ -584,6 +586,25 @@ public class MidiService extends IMidiManager.Stub { client.removeListener(listener); } + // Inform listener of the status of all known devices. + private void updateStickyDeviceStatus(int uid, IMidiDeviceListener listener) { + synchronized (mDevicesByInfo) { + for (Device device : mDevicesByInfo.values()) { + // ignore private devices that our client cannot access + if (device.isUidAllowed(uid)) { + try { + MidiDeviceStatus status = device.getDeviceStatus(); + if (status != null) { + listener.onDeviceStatusChanged(status); + } + } catch (RemoteException e) { + Log.e(TAG, "remote exception", e); + } + } + } + } + } + private static final MidiDeviceInfo[] EMPTY_DEVICE_INFO_ARRAY = new MidiDeviceInfo[0]; public MidiDeviceInfo[] getDevices() { -- 2.11.0