Android的蓝牙启用

问题描述

我开发一个蓝牙聊天应用程序。问题是，当我启用蓝牙应用程序启用蓝牙，但会导致强制关闭。下一次我启动相同的应用程序（带蓝牙功能），它工作顺利！我已经搜查，只得到了一些信息说，当我开始的意图启用蓝牙的code收益不等待意向的结果

 公共无效的run（）{

        // 1.检查蓝牙已启用
        如果（！blue.isEnabled（））{
            意图enable_Bluetooth =新的意图（
                    BluetoothAdapter.ACTION_REQUEST_ENABLE）;
            startActivityForResult（enable_Bluetooth，1）;

        }

        // 2.启动蓝牙服务器
        尝试 {
            服务器= blue.listenUsingRfcommWithServiceRecord（DHIRAJ
                    MY_UUID）;
 

解决方案

第一：

声明在应用程序清单文件中的蓝牙许可（S）。例如：

 ＆LT;舱单...＆GT;
＆LT;使用-权限的Andr​​oid：名称=android.permission.BLUETOOTH/＆GT;
...
＆LT; /舱单＆GT;
 

设置蓝牙：

  BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter（）;
如果（mBluetoothAdapter == NULL）{
//设备不支持蓝牙
}
 

启用蓝牙：

 如果（！mBluetoothAdapter.isEnabled（））{
意图enableBtIntent =新的意图（BluetoothAdapter.ACTION_REQUEST_ENABLE）;
startActivityForResult（enableBtIntent，REQUEST_ENABLE_BT）;
}
 

查找设备：

 设置＆LT; BluetoothDevice类＆GT; pairedDevices = mBluetoothAdapter.getBondedDevices（）;
//如果有配对设备
如果（pairedDevices.size（）大于0）{
//循环配对设备
对于（BluetoothDevice类设备：pairedDevices）{
    //添加姓名和地址到一个数组适配器在ListView显示
    mArrayAdapter.add（device.getName（）+\ N+ device.getAddress（））;
}
}
 

发现设备：

  //创建一个BroadcastReceiver的ACTION_FOUND
私人最终的BroadcastReceiver mReceiver =新的BroadcastReceiver（）{
公共无效的onReceive（上下文的背景下，意图意图）{
    串动= intent.getAction（）;
    //当发现找到的设备
    如果（BluetoothDevice.ACTION_FOUND.equals（动作））{
        //从意图获取BluetoothDevice类对象
        BluetoothDevice类设备=
intent.getParcelableExtra（BluetoothDevice.EXTRA_DEVICE）;
        //添加姓名和地址到一个数组适配器在ListView显示
        mArrayAdapter.add（device.getName（）+\ N+ device.getAddress（））;
    }
}
};
//注册的BroadcastReceiver
IntentFilter的过滤器=新的IntentFilter（BluetoothDevice.ACTION_FOUND）;
registerReceiver（mReceiver，过滤器）; //不要忘记的onDestroy期间注销
 

启用发现

 意图discoverableIntent =新
意图（BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE）;
discoverableIntent.putExtra（BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION，300）;
startActivity（discoverableIntent）
 

I am developing a Bluetooth chat application. The problem is that when i enable Bluetooth the application enables Bluetooth but causes force close. the next time i launch the same application(with Bluetooth enabled) it works smoothly ! i have searched and only got some information saying that when i start the intent for enable Bluetooth the code proceeds not waiting for the result of Intent

        public void run() {

        // 1. Check if Bluetooth is Enabled
        if (!blue.isEnabled()) {
            Intent enable_Bluetooth = new Intent(
                    BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enable_Bluetooth, 1);

        }

        // 2. Start Bluetooth Server
        try {
            Server = blue.listenUsingRfcommWithServiceRecord("dhiraj",
                    MY_UUID);

解决方案

first:

Declare the Bluetooth permission(s) in your application manifest file. For example:

<manifest ... >
<uses-permission android:name="android.permission.BLUETOOTH" />
...
</manifest>

Setting up bluetooth:

BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
// Device does not support Bluetooth
}

Enable bluetooth:

if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}

Finding devices:

Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
// If there are paired devices
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
    // Add the name and address to an array adapter to show in a ListView
    mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
}

discovering devices:

// Create a BroadcastReceiver for ACTION_FOUND
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
    String action = intent.getAction();
    // When discovery finds a device
    if (BluetoothDevice.ACTION_FOUND.equals(action)) {
        // Get the BluetoothDevice object from the Intent
        BluetoothDevice device =     
intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
        // Add the name and address to an array adapter to show in a ListView
        mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
    }
}
};
// Register the BroadcastReceiver
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy

Enabling discovery

Intent discoverableIntent = new
Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(discoverableIntent)

这篇关于Android的蓝牙启用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！