C++ (Cpp) BMediaRoster::GetAllInputsFor示例

void
AudioSettingsView::_FillChannelMenu(const dormant_node_info* nodeInfo)
{
	_EmptyMenu(fChannelMenu);

	BMediaRoster* roster = BMediaRoster::Roster();
	media_node node;
	media_node_id node_id;

	status_t err = roster->GetInstancesFor(nodeInfo->addon,
		nodeInfo->flavor_id, &node_id);
	if (err != B_OK) {
		err = roster->InstantiateDormantNode(*nodeInfo, &node,
			B_FLAVOR_IS_GLOBAL);
	} else {
		err = roster->GetNodeFor(node_id, &node);
	}

	if (err == B_OK) {
		int32 inputCount = 4;
		media_input* inputs = new media_input[inputCount];
		BPrivate::ArrayDeleter<media_input> inputDeleter(inputs);

		while (true) {
			int32 realInputCount = 0;
			err = roster->GetAllInputsFor(node, inputs,
				inputCount, &realInputCount);
			if (realInputCount > inputCount) {
				inputCount *= 2;
				inputs = new media_input[inputCount];
				inputDeleter.SetTo(inputs);
			} else {
				inputCount = realInputCount;
				break;
			}
		}

		if (err == B_OK) {
			BMessage message(ML_DEFAULT_CHANNEL_CHANGED);

			for (int32 i = 0; i < inputCount; i++) {
				media_input* input = new media_input();
				memcpy(input, &inputs[i], sizeof(*input));
				ChannelMenuItem* channelItem = new ChannelMenuItem(input,
					new BMessage(message));
				fChannelMenu->AddItem(channelItem);

				if (channelItem->DestinationID() == 0)
					channelItem->SetMarked(true);
			}
		}
	}

	if (Window())
		fChannelMenu->SetTargetForItems(BMessenger(this));
}