lifecycle

I have a bug in my code that made me think I don't fully understand the Android Lifecycle. Yes, I have read all the docs and looked at the diagrams, but they seem to talk only about when to save data, when the activity may loose focus or get killed. However, my question is if I don't need to save state, what happens to the variables & their stored values? I expected them to be destroyed to, but a bug in my code seems to indicate otherwise. In my case here is what happened. I have an activity that launches a custom view (no xml, I just draw bitmaps on the screen in my custom view). The only

Please correct me if I'm wrong on any of this. This is a kind of clarifying question since I haven't seen it explicitly written anywhere. In Android 4, you can call setRetainInstance(true) on a Fragment so that on configuration changes (which basically means device rotation), the Fragment java object isn't destroyed and a new instance of it isn't created. That is, the instance is retained. This is much more sane and less infuriating than in Android 1-3 since you don't have to deal with onRetainNonConfiguration State Instance() and bundle up all your data so it can be passed to the new Fragment

I have an entity in Doctrine2 and use the HasLivecycleCallbacks with PrePersist. In general this works fine, but I would like to change the version only, when certain fields in my entity change. Do I have a chance to get the old Values? Or just the keys that have been changed? /** * @ORM\HasLifecycleCallbacks */ class Person { /** * @PrePersist * @PreUpdate */ public function increaseVersion() { if ( $this->version == null ) { $this->version = 0; } // only do this, when a certain attribute changed $this->version++; } } Gordon It depends on which LifecycleEvent we are talking about. PrePersist

Spring is used in our team's Java EE project, and hibernate is used for underlying ORM. transactionManager is set like below: <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory" /> </bean> sessionFactory is set like below: <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="packagesToScan" value="com.company.model" /> <property name="hibernateProperties"> <value> hibernate.dialect=org

The javadoc and tutorial have information about the four applet lifecycle methods ( init() -> start() -> stop() -> destroy() ). But they talk mostly in abstract language. What I'm looking for are concrete examples of when it makes a difference if I put my code in init vs start , and similarly for destroy vs stop . The only thing I've found so far is in the tutorial's description of the destroy method. It says: Note: Keep implementations of the destroy method as short as possible, because there is no guarantee that this method will be completely executed. The Java Virtual Machine might exit