problem while switching between Portrait and landscape in android views

In my applica开发者_如何学运维tion im going to display a web page in web view , it works fine but if i flip between landscape to portrait or vice versa, then it exits and comes to main page. wht is the prblm?

logcat:

03-10 13:35:47.123: INFO/WindowManager(69): Setting rotation to 1, animFlags=1
03-10 13:35:47.242: INFO/ActivityManager(69): Config changed: { scale=1.0 imsi=310/260 loc=en_US touch=3 keys=2/1/1 nav=3/1 orien=2 layout=17 uiMode=17 seq=70}
03-10 13:35:47.363: INFO/UsageStats(69): Unexpected resume of com.mireader while already resumed in com.mireader
03-10 13:35:50.413: DEBUG/dalvikvm(69): GC_EXPLICIT freed 395 objects / 20424 bytes in 195ms

Since the device orientation is changing, the activity is destroyed then recreated.

This also leads the activity's contentview to be recreated.

See http://developer.android.com/reference/android/app/Activity.html#ConfigurationChanges for more details.