kindly help me to solve this problem I am unable to resume my activity once I get to the camera activity. - I have a button in my Camera activity to go to the next activity which is my OpenurlActivity
. but when I click on back button I got this error on my logcat:
08-15 17:49:55.518: E/AndroidRuntime(13628): FATAL EXCEPTION: main
08-15 17:49:55.518: E/AndroidRuntime(13628): java.lang.RuntimeException: Unable to
resume activity {com.example.qrreader/com.example.qrreader.CameraTestActivity}:
java.lang.NullPointerException
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.ActivityThread.performResumeActivity(ActivityThread.java:2825)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2854)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:1323)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.os.Handler.dispatchMessage(Handler.java:99)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.os.Looper.loop(Looper.java:137)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.ActivityThread.main(ActivityThread.java:5293)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
java.lang.reflect.Method.invokeNative(Native Method)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
java.lang.reflect.Method.invoke(Method.java:511)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
dalvik.system.NativeStart.main(Native Method)
08-15 17:49:55.518: E/AndroidRuntime(13628): Caused by: java.lang.NullPointerException
08-15 17:49:55.518: E/AndroidRuntime(13628): at
com.example.qrreader.CameraTestActivity.onResume(CameraTestActivity.java:510)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1202)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.Activity.performResume(Activity.java:5328)
08-15 17:49:55.518: E/AndroidRuntime(13628): at
android.app.ActivityThread.performResumeActivity(ActivityThread.java:2815)
08-15 17:49:55.518: E/AndroidRuntime(13628): ... 10 more
Why has this error occurred?
08-15 17:49:55.518: E/AndroidRuntime(13628): Caused by: java.lang.NullPointerException
08-15 17:49:55.518: E/AndroidRuntime(13628): at
com.example.qrreader.CameraTestActivity.onResume(CameraTestActivity.java:510)
You have to check a variable at row 510 to not be null.
i saw that the method called by onResume, the camera was null
Than you have what is the problem, obviously need to initialise the camera before that line and check if initialised. Maybe at onCreate.
At some point in your code you are setting mCamera
to null
.
It could be in your onPause
or onStop
methods, or even your onStart
or onResume
methods. Review the Activity Lifecycle
Try to realese the camera in onPause method
http://developer.android.com/training/camera/cameradirect.html#TaskReleaseCamera
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