如何prevent名称缓存和检测上发现蓝牙名称变更 [英] How to prevent name caching and detect bluetooth name changes on discovery

问题描述

我正在写一个Android应用程序从一个蓝牙设备接收信息。我们的客户建议，蓝牙设备（他们生产）将根据一定的条件下改变其名称 - 最简单的例子它的名字有时会XXX-ON，有时XXX-OFF。我的应用程序只是应该寻求这种BT发射器（我用BluetoothAdapter.startDiscovery（）），并做取决于它找到的名称不同的事情。我不与蓝牙设备配对（虽然我想这是可能的，应用程序应该是最终与多台Android设备和多个BT发射机工作，所以我不知道这将是一个不错的主意）。

I'm writing an Android app which receives information from a Bluetooth device. Our client has suggested that the Bluetooth device (which they produce) will change its name depending on certain conditions - for the simplest example its name will sometimes be "xxx-ON" and sometimes "xxx-OFF". My app is just supposed to seek this BT transmitter (I use BluetoothAdapter.startDiscovery() ) and do different things depending on the name it finds. I am NOT pairing with the Bluetooth device (though I suppose it might be possible, the app is supposed to eventually work with multiple Android devices and multiple BT transmitters so I'm not sure it would be a good idea).

我的code正常工作，检测设备BT，找到自己的名字。另外，如果设备熄灭，我可以检测下一次我求，这是不存在的。但似乎如果它是存在的，它改变了名字，我拿起旧名 - presumably被缓存的地方。即使蓝牙设备熄灭，我们注意到，下一次我发现了，我仍然看到旧名称。

My code works fine to detect BT devices and find their names. Also, if the device goes off, I can detect the next time I seek, that it is not there. But it seems that if it is there and it changes name, I pick up the old name - presumably it is cached somewhere. Even if the bluetooth device goes off, and we notice that, the next time I detect it, I still see the old name.

我发现在谷歌code这个问题：这里但它给我不清楚，甚至如何使用给出的解决方法（尝试连接）。有没有人这样做，任何运气？你可以分享code？

I found this issue in Google Code: here but it was unclear to me even how to use the workaround given ("try to connect"). Has anyone done this and had any luck? Can you share code?

有没有一种简单的方法，直接删除缓存的名字并重新搜索，所以我总能找到最新的名字呢？即使是一个非简单的方法将是很好（我写一个根深蒂固的设备）。

Is there a simple way to just delete the cached names and search again so I always find the newest names? Even a non-simple way would be good (I am writing for a rooted device).

感谢

推荐答案

我建议'fetchUuidsWithSdp（）。它的意义在于，不同的是类似getUuids（）方法，fetchUuidsWithSdp导致设备更新有关远程设备的缓存信息。我相信这包括远程名称以及社民党。

I would suggest 'fetchUuidsWithSdp()'. It's significance is that, unlike the similar getUuids() method, fetchUuidsWithSdp causes the device to update cached information about the remote device. And I believe this includes the remote name as well as the SPD.

请注意，这两个我提到的方法是隐藏之前4.0.3，所以你的code会看升艾克这样的：

Note that both the methods I mentioned are hidden prior to 4.0.3, so your code would look l ike this:

public static void startServiceDiscovery( BluetoothDevice device ) {
    // Need to use reflection prior to API 15
    Class cl = null;
    try {
        cl = Class.forName("android.bluetooth.BluetoothDevice");
    } catch( ClassNotFoundException exc ) {
        Log.e(CTAG, "android.bluetooth.BluetoothDevice not found." );
    }
    if (null != cl) {
        Class[] param = {};
        Method method = null;
        try {
            method = cl.getMethod("fetchUuidsWithSdp", param);
        } catch( NoSuchMethodException exc ) {
            Log.e(CTAG, "fetchUuidsWithSdp not found." );
        }
        if (null != method) {
            Object[] args = {};
            try {
                method.invoke(device, args);
            } catch (Exception exc) {
                Log.e(CTAG, "Failed to invoke fetchUuidsWithSdp method." );
            }               
        }
    }
}

您会再需要从它侦听BluetoothDevice.ACTION_NAME_CHANGED意图，并提取BluetoothDevice.EXTRA_NAME。

You'll then need to listen for the BluetoothDevice.ACTION_NAME_CHANGED intent, and extract BluetoothDevice.EXTRA_NAME from it.

让我知道是否有帮助。

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