i'm using this code to use the camera LED as flashlight but it crashes when the service starts. Using Log.w() statements i found it stops at param = camera.getParameters();. i have included the android.permission.CAMERA in my manifest. i don't understand what causes the crash. how can i fix this?
public class Flashlight extends Service {
private Camera camera;
private Parameters param;
private final IBinder mBinder = new LocalBinder();
public class LocalBinder extends Binder {
Flashlight getService() {
return Flashlight.this;
}
}
public int onStartCommand(Intent intent, int flags, int startId) {
Log.w("1","camera.open");
Camera.open();
Log.w("1","camera.getParameters");
param = camera.getParameters();
Log.w("1","i got camera parameters");
List<String> pList = camera.getParameters().getSupportedFlashModes();
if(pList.contains(Parameters.FLASH_MODE_TORCH)){
param.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
}
else if(pList.contains(Parameters.FLASH_MODE_ON)){
param.setFlashMode(Camera.Parameters.FLASH_MODE_ON);
}
param.setFocusMode(Camera.Parameters.FOCUS_MODE_INFINITY);
try{
camera.setParameters(param);
camera.startPreview();
}
catch (Exception e){
Toast.makeText(getApplicationContext(), "Your device does not have flash light support", Toast.LENGTH_SHORT).show();
}
return START_STICKY;
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
Parameters p=camera.getParameters();
p.setFlashMode(Parameters.FLASH_MODE_OFF);
camera.setParameters(p);
camera.stopPreview();
camera.release();
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
}
this is the LogCcat
12-15 15:44:32.037: W/1(26304): camera.open
12-15 15:44:32.347: W/1(26304): camera.getParameters
12-15 15:44:32.347: D/AndroidRuntime(26304): Shutting down VM
12-15 15:44:32.347: W/dalvikvm(26304): threadid=1: thread exiting with uncaught exception (group=0x40a9e228)
12-15 15:44:32.357: E/AndroidRuntime(26304): FATAL EXCEPTION: main
12-15 15:44:32.357: E/AndroidRuntime(26304): java.lang.RuntimeException: Unable to start service com.bill.deuterh.Flashlight@40dd0978 with Intent { cmp=com.bill.deuterh/.Flashlight }: java.lang.NullPointerException
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2738)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.app.ActivityThread.access$1900(ActivityThread.java:139)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1334)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.os.Handler.dispatchMessage(Handler.java:99)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.os.Looper.loop(Looper.java:154)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.app.ActivityThread.main(ActivityThread.java:4945)
12-15 15:44:32.357: E/AndroidRuntime(26304): at java.lang.reflect.Method.invokeNative(Native Method)
12-15 15:44:32.357: E/AndroidRuntime(26304): at java.lang.reflect.Method.invoke(Method.java:511)
12-15 15:44:32.357: E/AndroidRuntime(26304): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
12-15 15:44:32.357: E/AndroidRuntime(26304): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
12-15 15:44:32.357: E/AndroidRuntime(26304): at dalvik.system.NativeStart.main(Native Method)
12-15 15:44:32.357: E/AndroidRuntime(26304): Caused by: java.lang.NullPointerException
12-15 15:44:32.357: E/AndroidRuntime(26304): at com.bill.deuterh.Flashlight.onStartCommand(Flashlight.java:32)
12-15 15:44:32.357: E/AndroidRuntime(26304): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2715)
12-15 15:44:32.357: E/AndroidRuntime(26304): ... 10 more
i finally figured it out after a lot of trial end error.i'm posting the correct code for getting the parameteres, for other users with this problem
camera = Camera.open();
Camera.Parameters param = camera.getParameters();
Your camera object is null at
camera.getParameters()
. CallCamera.open()
in order to use it.Add a condition to check if the object is null first: