Develop Reference

Set different constraints for each orientation in Android Studio

The question sounds way harder than it is. Simply all I want to do is to be able to set a different layout for, I already added a landscape orientation, and recreated the whole design the way I desire in landscape. However, the app restarts each time I rotate the phone, if I add android:configChanges="orientation" in manifest, it does save the state but not the way I set in landscape. The app is 4 layouts in each orientation. So if I could just make different constraints for landscape the doesn't interrupt the original portrait it could solve my problem.
sorry for the poor explanation. It's my first week with Android.

You are correct in designing different layouts for different orientations.
For the state, you should override the onSaveInstanceState() method in Java.
Using that, you can save the state of the application and then inflate the layout the way you like in Java.

What's the most efficient way to change the overall theme of the app?

So I got an idea for an app that would change visual theme based on user's selection, something like how a Sub-Reddit would have the option for users to switch between themes. In this case, I would utilize at least 4 themes, each theme changing the color of certain views, such as the background, buttons, image, and etc. I would like to know the the best approach to this. Do I need to keep a list of views that would be affected or something?
I've tried keeping different button backgrounds with different color since setting background color programmatically would reset the background shape back to the default design, but I'm afraid that it will cause the app to be bloated with numerous files. I've tried using the color filter to change the views.
Color id still keeps the filter applied to it, causing it be unusable if user switch to different color, then back.

Hopefully, this question was directed at native development. If so, then you should take a look at the guidelines. You can create your themes in XML and reference them in your layout XML files.
Personally, I would store the theme as a SharePreference somewhere and then when laying out each Activity/Fragment, utilize the user's saved theme.

How to create a custom android button overlay?

So to expand on the question stated, to my best understanding android apps have a set of activities such as the default activity_main.xml and you could even generate a login screen (activity_login.xml). After fiddling around with it I sort of feel comfortable with the way buttons work, yadda yadda, but my problem emerges when I want to create a game activity. I am not concerned about that part, I would just make another activity (activity_gameplay.xml) that I would run the game on. My problem is that I want to render my own custom buttons onto the screen which would be transparent and would be stationary while the actual game environment would be moving. Such as in Minecraft(android version obviously).
So to conclude I need to know how to render custom buttons, and though not included in the above, how to position the buttons accordingly sense the XML way only allows stuff such as upper left-hand corner etc.

managing Persistent Visual Data (event driven buttons and ImageViews) throughout Activities of an application

I need some advice for those who are experienced making Android applications. What I would really like to have, for my application's appearance: at the top, a title-bar which is a ImageView (content is a png), and at the bottom a series of custom buttons which make up a tab-bar like thing. In between the title and the tab-bar is the Content, which may be anything... (most likely buttons)
I have been doing this by making a RelativeLayout which specifies LeftMargin and UpperMargin for x,y coordinates--
Currently all of my activities are inheriting a custom MyActivity class, which rebuilds the title and the tab-bar at the time of onCreate. This seems bad to me!
PART1)
---A solution to Persistent data
Since the "tab-bar" and the title are persistent no matter what screen you're on during this application's run-time, it makes the most sense to store them somewhere... How should I do this? Make a singleton object that the Activity's ask for?
I thought a little about the singleton object, and I'm not even sure what I would store, since the Views that are on displayed during Activity A have activity A as context, and not Activity B.
PART2)
---Animation Aesthetics
I would really like to have the "Content" (the view in the middle between title and tabbar) slide out to the left, and the new content slide in from the right. I.e, I'd like the tab-bar and the title to remain fixed while the "activities" change. is this at all possible? What should I do to achieve it?
one idea I had, was to make all of the program in one activity! I would create an animation for the Custom View in the middle, and I would override the "back" button to navigate correctly to the previous Custom View. Is that a horrible idea?
Anyone have any advice?

Read http://developer.android.com/design. Most of the design principles can be applied to apps that run on legacy releases; it's not just limited to Honeycomb and Ice Cream Sandwich. Do consider the Action Bar and Dashboard design patterns.
I don't really recommend using just one Activity -- generally, an Activity should be a separate, encapsulated, pretty well defined chunk of functionality that can execute independently of other Activities.
To avoid duplication of your UI, consider reusing XML layouts.
To avoid duplication of your logic, consider using Fragments. You should be able to mix and match them in your activities.
To achieve the animation you describe, consider implementing a ViewPager.
Using the ActionBarCompat sample app and Android Support Library, you can enjoy modern goodies like Action Bar, fragments, tabs, and horizontal sliding transitions on devices running Android all the way back to Donut (1.6).

is multiple activities and surface views the correct way to go?

I'm currently in the process of making one of my first android games and have come into some difficulty understanding how to make the transitions between screens.. for example:
My game starts its main activity, which then loads TitleScreen surface view which initializes its own thread
on tap I start a new intent which loads a new activity which loads GameView surface view which initializes its own thread
This all works fine when testing on my device (Evo 3d) but crashes on tap on my test bed, I'm using android x86 in virtual box for quick testing. Is this likely to be a problem in my code or a problem with the simulator?
Also I'm wanting to add a level select screen in between the title screen and the game screen and figured i could do this by creating another activity/surface view/thread combo, Is this acceptable coding practice or is this a wasteful/process heavy method?

You could create a variety of methods that you call from your onDraw method. Each method would draw one screen (game, level, score). To start simple a switch case in the onDraw checks the screen and then calls the right thing to draw.
If you want to have different layers, you should use different acitvities so that the background (game) is being paused while the scoreboard is active. This only makes sense if you want the background to be still visible or need the acitivites for other reasons.
But you should never have more than one surface view active at the same time, android doesnt like that.

I think its not good to use more activities for single application. Try to use ViewFlipper with number of xml layout files. Here you can apply transition effects very easily.
I am suggesting you it for transition effects, but you also check it once. I am also thinking which one is good.