Develop Reference

"Empty" container to set as another UI element's parent

I'm re-writing my app with this layout in Android (using Android Studio 3.6 & Java 8) and noticed that I can't directly set the background color of an EditText or Spinner because the background used contains the e.g. EditText's line (the line the text is written on).
To work around that in my iOS app I simply gave that UI element (with an otherwise transparent background) a View parent that uses the right background color. In Android Studio this works the same way if I use an e.g. LinearLayout as parent but I don't need that layout's full functionality and I'm worried that "abusing" LinearLayouts like this multiple times might affect performance.
There is a View widget in Android Studio but it's not possible to add an EditText or Spinner as its child.
Are there any layouts/views that can be added via Android Studio's UI builder or through xml and that act as the "empty" container I need? What's the best layout to use performance-wise?

Is there anyway to use my android studio without this new constraint Layout?

I learnt about Relative and LinearLayout, but now the newly upgraded android studio 2.3.. is automatically using this constraint Layout which i know absolutely nothing about.
Why does the constraint Layout choose automatically what i need in my own project? Is there any way to use my android studio without these constraint layout? which is by the way, very annoying!

ConstraintLayout is similar to RelativeLayout. ConstraintLayout allows you to create large and complex layouts with a flat view hierarchy,
Here is official tutorial for constraint Layout.
If you wish to change default layout. You can do that by editing default template file, which are located in:
...\Android\Android Studio\plugins\android\lib\templates\activities
replace ConstraintLayout with RelativeLayout (or your favorite layout!) using any text editor.
for detailed information please refer this answer

Seen the rest of the layout when using the ScrollView in android studio

I have android studio. But when using the ScrollView to design the layout and etc in inside the screen, I have a problem and when I want to add the additional tools greater than the screen, I can not do this action.Also I have the android studio old version.

You need to edit the xml of the view that you want to Put it out of the screen. For example to put it outside the right bound. Simply add
android:layout_marginRight="-250dp"

All objects move when I drag one around

I am creating an Android app in Eclipse, but when I drag around a TextView, everything below it moves around as well.
This is when I haven't dragged anything.
http://i.stack.imgur.com/Twp4L.png
This is when I drag the TextView just a bit.
http://i.stack.imgur.com/oJ75k.png

The layout designer doesn't work very well in Eclipse. You could try Android Studio's layout designer (the new early access preview), that one is a bit better, but not by much.
The most common practice is to use the layout designer to only get started with and perhaps to use the Outline view panel to tweak some of the nesting of the layouts/views by dragging some of the nodes inside it, but then it's to dive directly into the xml code yourself. There is really no other substitute for doing that. The tool just isn't very good yet.

This is called a Relative Layout. In this case, the components are placed relative to the TextView, which is not so unexpected. It depends how you set relations in the layout XML. What layout you want to achieve?
You can either set that all the components are placed relative to the whole view, or use some specialized layout types like LinearLayout. It all depends on the effect you want to achieve.

How to disable auto alignment?

I'm building an android project and I'm using eclipse.
I just can't figure out how to disable the annoying auto alignment.
I just want to place buttons wherever I want to drop them on the GUI interface but it just keeps
to align them one to another. I've tried to delete those alignment lines in the xml code
but it still brings them back as I move the buttons on the GUI interface.
Is there an way to disable that function?
Thank you,
Alex

Is there an way to disable that function?
Not in a way that you will find satisfactory, I suspect.
You have not really explained what the "alignment lines" are, so we are forced to guess. My guess is that the "alignment lines" are because you are working with a RelativeLayout container. Quoting the JavaDocs for RelativeLayout, RelativeLayout is:
A Layout where the positions of the children can be described in relation to each other or to the parent.
And, quoting the guide for RelativeLayout:
RelativeLayout is a view group that displays child views in relative positions. The position of each view can be specified as relative to sibling elements (such as to the left-of or below another view) or in positions relative to the parent RelativeLayout area (such as aligned to the bottom, left of center).
Hence, the "alignment lines" are there, and are replaced by the GUI builder, because they are the point behind using a RelativeLayout container.
Of course, you are welcome to change the container that you are working with to something else.
However, in general, Android does not really support very well your stated objective ("I just want to place buttons wherever I want to drop them on the GUI interface"). Just as you don't do that in Web development, you don't do that in Android development, and for much the same reason: you need to take different sizes into account (browser window size for Web, screen size for Android). RelativeLayout, LinearLayout, TableLayout, and GridLayout are all designed to have you specify widgets plus rules for positioning and sizing, so that you can design a UI that will accommodate the difference between a 3" and a 4.5" screen, for example. This is akin to using HTML tags and CSS rules to define content and its positioning in a Web page. Eclipse's drag-and-drop GUI builder for Android can assist in your definitions of these rules, as you are perhaps seeing with your "alignment lines" for RelativeLayout.

I think I may be able to help. If you set your layout to Relative Layout you can drag and drop any of the views wherever on the eclipse GUI.