我开发了一款在Jelly Bean（Android 4.3）上使用蓝牙功能的应用程序。我注意到Lollipop的蓝牙类有一套不同的方法。当我在Lollipop上运行我的应用程序时，它失败了。
我了解到我可以在运行时添加代码以支持不同的API级别，例如：
private void startScanBluetooth(){
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Method supported in Lollipop
mLeScanner.stopScan(mScanCallback);
}
else {
// Method for older API level
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
}
我的代码有 BluetoothAdapter.LeScanCallback ，它位于我的“活动类”中但不在任何方法之内。
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.title_bar);
setContentView(R.layout.device_list);
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
//....
}
private BluetoothAdapter.LeScanCallback mLeScanCallback =
new BluetoothAdapter.LeScanCallback() {
@Override
public void onLeScan(final BluetoothDevice device, final int rssi, byte[] scanRecord) {
runOnUiThread(new Runnable() {
@Override
public void run() {
runOnUiThread(new Runnable() {
@Override
public void run() {
//String targetDevice = MainActivity.targetDevice.getText().toString();
//if(targetDevice==null || targetDevice.length()==0 || targetDevice.equals(device.getName()))
addDevice(device,rssi);
}
});
}
});
}
};
由于这个回调已被弃用，我需要一个新的回调方法： ScanCallBack 来支持Lollipop，所以我添加了另一个回调：
mScanCallback = new ScanCallback() {
@Override
public void onScanResult(int callbackType, ScanResult result) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
Log.i("callbackType", String.valueOf(callbackType));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
Log.i("result", result.toString());
BluetoothDevice btDevice = result.getDevice();
connectToDevice(btDevice);
}
}
}
};
它现在可以在Lollipop中运行，但是当我在4.4.2上运行时，应用程序在运行Class DeviceListActivity 时会出现意外情况（以上所有内容都在此类中。）失败的是：
09-02 17:42:46.469 15329-15329/com.conerstoneee2.blecaller D/OLED: Start DeviceListActivity now
09-02 17:42:46.499 15329-15329/com.conerstoneee2.blecaller D/OLED: onPause
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: Unable to resolve superclass of Lcom/conerstoneee2/blecaller/DeviceListActivity$3; (63)
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: Link of class 'Lcom/conerstoneee2/blecaller/DeviceListActivity$3;' failed
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller E/dalvikvm: Could not find class 'com.conerstoneee2.blecaller.DeviceListActivity$3', referenced from method com.conerstoneee2.blecaller.DeviceListActivity.<init>
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve new-instance 1960 (Lcom/conerstoneee2/blecaller/DeviceListActivity$3;) in Lcom/conerstoneee2/blecaller/DeviceListActivity;
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x22 at 0x0006
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to find class referenced in signature (Landroid/bluetooth/le/ScanCallback;)
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller I/dalvikvm: Could not find method android.bluetooth.le.BluetoothLeScanner.startScan, referenced from method com.conerstoneee2.blecaller.DeviceListActivity.scanLeDevice
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve virtual method 311: Landroid/bluetooth/le/BluetoothLeScanner;.startScan (Landroid/bluetooth/le/ScanCallback;)V
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x6e at 0x0024
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller I/dalvikvm: Could not find method android.bluetooth.le.BluetoothLeScanner.stopScan, referenced from method com.conerstoneee2.blecaller.DeviceListActivity.scanLeDevice
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve virtual method 312: Landroid/bluetooth/le/BluetoothLeScanner;.stopScan (Landroid/bluetooth/le/ScanCallback;)V
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x6e at 0x0041
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller I/dalvikvm: Could not find method android.bluetooth.BluetoothAdapter.getBluetoothLeScanner, referenced from method com.conerstoneee2.blecaller.DeviceListActivity.onCreate
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve virtual method 283: Landroid/bluetooth/BluetoothAdapter;.getBluetoothLeScanner ()Landroid/bluetooth/le/BluetoothLeScanner;
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x6e at 0x0071
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller I/dalvikvm: Could not find method android.bluetooth.le.BluetoothLeScanner.stopScan, referenced from method com.conerstoneee2.blecaller.DeviceListActivity.onDestroy
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve virtual method 312: Landroid/bluetooth/le/BluetoothLeScanner;.stopScan (Landroid/bluetooth/le/ScanCallback;)V
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x6e at 0x0014
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller I/dalvikvm: Could not find method android.bluetooth.le.BluetoothLeScanner.stopScan, referenced from method com.conerstoneee2.blecaller.DeviceListActivity.onStop
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: VFY: unable to resolve virtual method 312: Landroid/bluetooth/le/BluetoothLeScanner;.stopScan (Landroid/bluetooth/le/ScanCallback;)V
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: VFY: replacing opcode 0x6e at 0x0014
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: Unable to resolve superclass of Lcom/conerstoneee2/blecaller/DeviceListActivity$3; (63)
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: Link of class 'Lcom/conerstoneee2/blecaller/DeviceListActivity$3;' failed
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/dalvikvm: DexOpt: unable to opt direct call 0x3ea0 at 0x08 in Lcom/conerstoneee2/blecaller/DeviceListActivity;.<init>
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller D/AndroidRuntime: Shutting down VM
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x41f8bda0)
09-02 17:42:46.519 15329-15329/com.conerstoneee2.blecaller E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.conerstoneee2.blecaller, PID: 15329
java.lang.NoClassDefFoundError: com.conerstoneee2.blecaller.DeviceListActivity$3
at com.conerstoneee2.blecaller.DeviceListActivity.<init>(DeviceListActivity.java:181)
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1208)
at android.app.Instrumentation.newActivity(Instrumentation.java:1067)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2289)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2453)
at android.app.ActivityThread.access$900(ActivityThread.java:173)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5579)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1268)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1084)
at dalvik.system.NativeStart.main(Native Method)
09-02 17:42:49.959 15329-15329/com.conerstoneee2.blecaller I/Process: Sending signal. PID: 15329 SIG: 9
更新 感谢@Jesse指出我可以在回调中添加用于检查构建版本的代码。它可以成功构建APK，但现在它无法在4.4.2中运行
答案 0 :(得分：1)
你关闭了。 BluetoothAdapter.LeScanCallback是一个界面。当你这样做时：
private BluetoothAdapter.LeScanCallback mLeScanCallback =
new BluetoothAdapter.LeScanCallback() {
@Override
public void onLeScan(final BluetoothDevice device, final int rssi, byte[] scanRecord) {
runOnUiThread(new Runnable() {
@Override
public void run() {
runOnUiThread(new Runnable() {
@Override
public void run() {
//String targetDevice = MainActivity.targetDevice.getText().toString();
//if(targetDevice==null || targetDevice.length()==0 || targetDevice.equals(device.getName()))
addDevice(device,rssi);
}
});
}
});
}
};
＆＃34;它位于[您的]活动类中但不在任何方法之外。＆＃34;这段代码没有发生任何事情。当你这样称呼时：
mLeScanner.stopScan(mScanCallback);
并将其作为参数传递。如果需要，mLeScanner会使用该回调。
因此，只需创建额外的回调方法（不要检查构建版本）。
private **typeNameGoesHere** mScanCallback = new ScanCallback() {
@Override
public void onScanResult(int callbackType, ScanResult result) {
Log.i("callbackType", String.valueOf(callbackType));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
Log.i("result", result.toString());
BluetoothDevice btDevice = result.getDevice();
connectToDevice(btDevice);
}
}
};
然后保持你的startScanBluetooth方法原样，你应该没事。
private void startScanBluetooth(){
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Method supported in Lollipop
mLeScanner.stopScan(mScanCallback);
}
else {
// Method for older API level
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
}