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This article will explain in detail how to analyze Android program conversion, the content of the article is of high quality, so the editor will share it for you to do a reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.

In Android programs, the restrictions on the value of default variables are very vague. Based on this, many compilers allow developers to include default variable values in function declarations, pointers and references to functions, pointers to member functions, and typedef declarations.

The state of Activity and the transition between states in Android programs, Activity has four basic states: Active/Runing, after a new Activity is launched into the stack. It is at the front end of the screen, at the top of the stack, when it is visible and can interact with the user. Paused the state when the Activity is overwritten by another transparent or Dialog-style Activity.

At this point, it is still connected to the window manager, and the system continues to maintain its internal state, so it is still visible, but it has lost focus and cannot interact with the user.

Stoped is in the Stoped state when Activity is lost focus and is not visible by another Android program. Killed Activity is in the Killed state when it is killed by the system for recycling or when it is not started.

When an Activity instance is created, destroyed, or started another Activity, it transitions between these four states, depending on the actions of the user program. The following figure illustrates the timing and conditions for the transition of Activity between different states: the platform can promote the innovation of mobile devices and let users experience more mobile services. At the same time, developers will also get a new level of openness.

As shown above, Android programmers can decide the "life" of an Activity, but not its "death", that is, programmers can start an Activity, but cannot manually "end" an Activity. When you call the Activity.finish () method.

The result is the same as when the user presses the BACK key: tell Activity Manager that the Activity instance has done its job and can be "recycled". Then the Activity Manager activates the Activity at the second layer of the stack and reenters the stack, while the original Activity is pushed into the second layer of the stack and changes from the Active state to the Paused state.

For example, if you start Activity2 from Activity1, the one currently at the top of the stack is Activity2, and the second layer is Activity1. When we call the Activity2.finish () method, Activity Manager reactivates Activity1 and enters the stack. Activity2 transitions from Active state to Stoped state, Activity1. The onActivityResult (int requestCode, int resultCode, Intent data) method is executed, and the data returned by Activity2 is returned to Activity1 through the data parameter.

On how to parse the Android program conversion to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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