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HorizontalScrollView's child not matching it's parent view's width even on setting android:layout_width="match_parent"

I want to display a horizontal list of scrollable buttons at top of the phone screen containing 30 items, for this purpose I am using a HorizontalScrollView with a LinearLayout with "horizontal" orientation as it's child but the linear layout is not taking up the entire phone width even on setting its width as "match-parent". Here's the code :
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:layout_gravity="center">
<GridView
android:id="#+id/gridView_horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:stretchMode="columnWidth" />
</LinearLayout>
</HorizontalScrollView>
Here is shown in the image that linear layout is not taking up the entire space and LinearLayout is only covering some of the space. Also on changing the size to a fixed size, I noticed that the HorizontalScrollView was actually behaving like a vertical Scroll View only.
NOTE: Also if there is an alternative way to display a horizontal list of buttons with 30 items with numbers from 1 to 30 on it, please suggest it.

To achive this easily you may use Recyclerview with Horizotanl Layout Manager.For Example
recycler_view.setLayoutManager(new LinearLayoutManager(MainActivity.this, LinearLayoutManager.HORIZONTAL, false));

I don't think you need a HorizontalScrollView with a nested LinearLayout for what you are trying to achieve. It would be a better idea to simply use a horizontal RecyclerView if your button layouts are similar and the functionality of the buttons is similar too. Refer to this answer for help https://stackoverflow.com/a/40584425/9119277

Resize Height Listview when Move button under ListView

In my app I have a listview and a button under Listview(button in footer listview or set under list in relative layout)
Now i want when i move button (up or down) height of listview will change.
How i do?
Thank for any ideal or solution!

I will assume that you are referring to a resize when you say move. For this, it is better to use a LinearLayout instead of a RelativeLayout.
Just set the android:layout_weight property of the ListView to 1.
Example:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
When you do this, the Button will occupy the amount of space it requires and the ListView will take the remaining space and also scale accordingly.

Have elements equally span entire width / height of their RelativeLayout

I have, say three buttons i would like to list below one another in a layout. Depending on the device, screen size, pixel density, orientation and so on, i would like the buttons to span the entire height of their parent layout. The buttons each have a fixed height (dp), so the spanning is more likely concerning the space between the buttons.
I saw several questions on various forums regarding how a LinearLayout is supposedly a fix for this problem, by nesting a layout for each element, having the layout span. I would very much like to avoid nesting layouts, and I'm using a RelativeLayout as of now, so if there is any way to go about it with this type of layout it will be of great help! :)
Additionally, I would like the top and bottom button to "touch" the parent layout border at the top and bottom, and the last (or rest) button to fill out the rest of the vertical space equally.
Thank you in advance.

I'm not entirely sure what you wish to achieve, but you should be able to do this using a LinearLayout & weights (so you don't have to nest multiple layouts).
If you want the 3 buttons to take up the entire parent of the screen just add a weight to each for example:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:id="#+id/button_one"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<Button
android:id="#+id/button_two"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<Button
android:id="#+id/button_three"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
</LinearLayout>

Try to set to topButton a field in XML:
android:layout_alignTop="true";
Try to set to middleButton a field in XML:
android:layout_centerVertical="true";
Try to set to bottomButton a field in XML:
android:layout_alignBottom="true";

Layout troubles

I am having a spot of bother with a fairly simple layout. Here it is:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="#+id/id1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:ellipsize="end"
android:maxLines="1"/>
<TextView
android:id="#+id/id2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"/>
</LinearLayout>
3 Questions:
How do I center vertical both TextViews (or perhaps better said, the text within those views) within the parent LinearLayout? The left view is vertically centered OK, but the right one (because it has a smaller font) is not. It seems to be centered vertically at the top. I obviously tried playing with layout_gravity of the second view but that makes no difference whatsoever. The only way I can solve it is to wrap the second TextView in a LinearLayout with its layout height parameter set to match_parent (but is this the correct way of doing this?)
Similarly, I want the View on the left horizontally centered on the left, and the View on the right horizontally centered on the right. Currently the right View is placed immediatly next to the left one. The only way I can solve this is by adding something like this inbetween the two text views:
<TextView
android:layout_width="0dip"
android:layout_height="fill_parent"
android:layout_weight="1"
android:text="">
basically acting as a spacer which decreases in size depending on the legth of the text in both TextViews
I want the text in the left View to be truncated if the combined text of the Views does not fit horizontally. No wrapping onto a new line. Currently the text in the left View simply "pushes" the right one out of the parent. No idea how to achieve that (apart from adding android:maxLines="1" to stop the text from wrapping). I have tried android:ellipsize="end" but that does not seem to have any effect.

Best way is to use Relative layout , but still if you want to do the same thing in Linear layout than do some changes in your xml file
-First is set Linear layout hight as match parent :
<LinearLayout android:layout_width="fill_parent"
android:layout_height="match_parent"
android:orientation="horizonatal">
-Second for making the views visible at centre vertical do
android:layout_gravity="center_vertical"
same property android:layout_gravity = "center_horizontal" , you have to add in second text view also.
It will make your both text view appear at centre vertical but one next to other.
To make the second view appear on right I think you can add
android:layout_marginLeft="xx dp"
put some value in place of xx.
For your third question about truncating your text, you should give some size to your TextView not wrap content..Like android:layout_width ="25dp"
and then use android:ellipsize="end".
I guess you will get that..Actually I am in hurry,time to leave the office.

Which of layout should i use?

I'm confused. I want to show the map and on below of map show 5 buttons. I use RelativeLayout, but the program just show Product button. Why? I'm confused which layout i use (Linear,Relative,Frame or absolute )!! Please help me. and How can i correct this code?
location.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/frame"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<com.google.android.maps.MapView
android:id="#+id/mapView"
android:apiKey="0cPRv243zM1_S3ydsNg8MJP9_6BfCp642jOhPvQ"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/background"
android:layout_gravity="bottom"
android:orientation="horizontal" >
<Button
android:id="#+id/button_home"
style="?android:attr/borderlessButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableTop="#drawable/home_icon"
android:text="#string/button_home"
android:textColor="#color/text_home" />
<Button
android:id="#+id/button_product"
style="?android:attr/borderlessButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableTop="#drawable/product_icon"
android:onClick="Product"
android:text="#string/button_product"
android:textColor="#color/text_product" />
</LinearLayout>
</LinearLayout>

To answer your specific problem: Instead of saying that the home button is to the left of the product button, you should say that the product button is to the right of the home button. When a RelativeLayout is inflated, the layout is parsed in a linear way so if view A it positioned relative to view B, view B must come first.
<Button
android:id="#+id/button_home"
style="?android:attr/borderlessButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableTop="#drawable/home_icon"
android:text="#string/button_home"
android:textColor="#color/text_home"/>
<Button
android:id="#+id/button_product"
style="?android:attr/borderlessButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/button_home"
android:drawableTop="#drawable/product_icon"
android:onClick="Product"
android:text="#string/button_product"
android:textColor="#color/text_product" />
Add this to the product button and delete the layout_toLeftOf from the home button.
android:layout_toRightOf="#id/button_home"
You can use gravity and alignment to position the home button and then have the other four buttons following it, each one positioned to the right of the one before it.
Good luck

RelativeLayout by default places these 2 buttons together, so you can just see the latter.
And the line
android:layout_toLeftOf="#+id/button_product"
is wrong. #+id creates an id, use #id in such cases.
I would recommend LinearLayout for the situation. Place these buttons in it, and adjust them with some margin.

LinearLayout : LinearLayout is used when we need to arrange the
widgets/views in a horizontal or vertical manner.
The direction of arrangement can be set to horizontal or vertical,
by default it is being horizontal.
TableLayout : If the Layout's widgets/views need to be arranged
in the form of rows and columns, we use this layout object.
This is similar to html tables. The cells can span columns.
The TableLayout do not display its border. We can be made to
shrink and stretch by setting the respective properties of the columns,
"TableRow" is another helper widget which should be used in conjunction
with the TableLayout.
RelativeLayout : Here the position of each of the widgets/view is
in relative/dependent to each other. For example, when a layout is needed
such that it has a text view just to the left of an Edit Textbox, and a button
just below the EditText. The relation between the views are taken care in
one iteration, hence if view B’s position is dependent on view A’s position,
view A must come first in the layout.
FrameLayout : This is a very simply layout which is used to hold a section
of the screen blank, for displaying an item or group of items at run time. All the
elements added in the framelayout will be added to the top left of the screen.
AbsoluteLayout : When there is a need is to specify exact x and y co-ordinate
position of the view, then AbsoluteLayout need to be used. This layout is
difficult to maintain.