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Centre text inside a Cardview - Android Studio

I'm currently using a Card View inside a recycler and the text is left-alligned despite my efforts.
Here is the Book Item Layout.
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content"
android:layout_width="match_parent"
app:cardCornerRadius="4dp"
app:cardElevation="5dp"
app:cardUseCompatPadding="true"
app:cardBackgroundColor="#color/white">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<TextView
android:id="#+id/bookTitleTextView"
android:layout_width="wrap_content"
android:layout_height="match_parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_gravity="center_horizontal"
/>
</LinearLayout>
</androidx.cardview.widget.CardView>
Here is the recycler itself.
<?xml version="1.0" encoding="utf-8"?>
<androidx.recyclerview.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/bookRecycler" />
This is the current output.
enter image description here
As you can see the text is not centered.
I tried using layout gravity to center the text which didn't work.
I also tried using a constraint layout on the text view and using constraints to center the text without any luck.
android:layout_gravity = "center" has already been attempted.
Any advice on what I'm overlooking would be great.
Thank you.

add android:gravity="center" for LinearLayout and you are good to go
I see your LinearLayout have only one child and no special attributes, so you can even remove whole LinearLayout - place TextView straight inside CardView, which extends FrameLayout. For centering childs inside FrameLayout you may also use android:gravity="center" for parent and/or android:layout_gravity="center" for child
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:gravity="center"
app:cardCornerRadius="4dp"
app:cardElevation="5dp"
app:cardUseCompatPadding="true"
app:cardBackgroundColor="#color/white">
<TextView
android:layout_gravity="center"
... rest of code

android:gravity="center" is the correct code, instead of android:layout_gravity="center_horizontal"

ListView in Fragment not covering full Parent

I have a ListView in a Fragment which isn't covering the whole Parent when the List isn't fully populated.
The Problem is the scrolling behaviour of the ListView, I can only browse in the small piece of window the ListView is initially loaded in.
(4 Entries or more do occupy the entire Parent, with less entries the problem happens)
Fragment:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:divider="#null"
/> </LinearLayout>
Main XML:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<FrameLayout
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
/>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="?android:attr/windowBackground"
app:itemBackground="#color/bgBottomNavigation"
app:itemIconTint="#android:color/white"
app:itemTextColor="#android:color/white"
app:menu="#menu/navigation" />
</android.support.design.widget.CoordinatorLayout>
The ListView gets populated via Volley + JSON with an Adapter for the ListView. Comment if you need the Code.
When I'm trying to put the ListViews height on "match_parent" the whole screen is occupied by the ListView, but it isn't scrollable anymore.
What can I do?
EDIT:
Coordinator Layout - This is the Code of the Frame Coordinator with the Bottom Navigation in it:
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<FrameLayout
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="?android:attr/windowBackground"
app:itemBackground="#color/bgBottomNavigation"
app:itemIconTint="#android:color/white"
app:itemTextColor="#android:color/white"
app:menu="#menu/navigation" />
</android.support.design.widget.CoordinatorLayout>

You could set a minimum height attribute to your listView and adjust to what suits you.
Eg. to set it to 20dp, add android:minHeight="20dp" to your listView attributes.
Best solution would be to wrap all the contents of the CoordinatorLayout inside a layout you can control yourself, like a ConstraintLayout. In that case you would align the FrameLayout (and the fragments it handles) between your other components and everything would be scrollable and clickable. A mock of this solution would be:
<CoordinatorLayout>
<ConstraintLayout height="match_parent">
<BottomNavigation bottomToBottomOf="parent" />
<FrameLayout height="0dp"
topToTopOf="parent"
bottomToTopOf="bottomNavigation" />
</ConstraintLayout>
</CoordinatorLayout>

putting recycler view above bottom navigation

i have a bottom navigation in main activity and what I'm trying to do is to show recyclerview above bottom navigation but my problem is bottom navigation is overlapping recyclerview and my recyclerview is in map fragment so that is why I'm not able to put it above bottom navigation i tried using margin but its cuts the recyclerview
my xml code
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.google.android.gms.maps.MapView
android:id="#+id/mapview"
android:layout_width="match_parent"
android:layout_height="match_parent">
</com.google.android.gms.maps.MapView>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.RecyclerView
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_width="match_parent"
android:layout_height="150dp"
android:id="#+id/item_picker">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
</RelativeLayout>

Try this
android:layout_above="#+id/navigationLayout"
<android.support.v7.widget.RecyclerView
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_above="#+id/navigationLayout"
android:id="#+id/item_picker"/>

You are trying to set RecyclerView at the bottom of parent that's why your UI is overlapping.
Try this,
android:layout_below="#+id/mapView"
android:layout_above="#+id/yourBottomNavigationView"
So that it will not overlap with each other.

ListView and Button

I have a custom ListView. This ListView contains Bluetooth Devices found during a Scan. I want to have the possibility to click on one single item (i.e. Bluetooth Device) of the list and at the end of the list I want a Button, that allows me to connect to the selected Device.
The problem is that I can't get a single button at the end of the list, but I have a button for each item of the list.
This is my XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".DeviceScanActivity"
tools:ignore="ExtraText">
<ListView
android:id="#+id/list"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1">
</ListView>
<TextView
android:id="#+id/device_name"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="20sp" >
</TextView>
<TextView
android:id="#+id/device_address"
android:textSize="12sp"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</TextView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/connectButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Connect"
android:onClick="ConnectButton"
android:layout_gravity="center">
</Button>
</LinearLayout>
</RelativeLayout>

Why do you only have weight on your ListView and not your other Layout objects?
Try this:
1)Change your parent layout from relative to Linear (Vertical).
2)Nest everything outside of the ListView (Your texts and Button) in another Linear (or any other) layout. Then set both your ListView and other view's height to "0dp". Also add weights to them, based on your preference; I'd say probably something like 6:1 or 7:1 (big numbers for ListView and small number for your other layout containing buttons)
This should show them at the bottom of your ListView

Use RelativeLayout outside CoordinatorView

I have a CoordinatorLayout, in where a RecyclerView displays some CardViews, defined in an other layout. Under this scrollable view, i am trying to add a RelativeLayout, which inherits fields for text input, buttons for sending it, etc.
The problem: CoordinatorLayout seems to block the whole screen, although i told to wrap contents height. Nevertheless, RelativeLayout is added (tested it by setting Coordinator-height = 50dp), but off-screen. What is wrong here?
PS: I know how to solve it with android:layout_weight=xx. But thats not what i want to achieve, because it blocks my EditText to expand, if bigger texts are entered.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.CoordinatorLayout
android:id="#+id/data_coordinator_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</android.support.design.widget.CoordinatorLayout>
<RelativeLayout
android:id="#+id/delete_data_layout"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_below="#id/data_coordinator_layout">
<EditText/>
<Button/>
<Button/>
<Button/>
</RelativeLayout>
</RelativeLayout>

It's actually pretty simple. You need to align your Relative Layout (delete_data_layout) to bottom of your parent. Then you make the Coordinator layout above the Relative Layout. This causes, that Coordinator layout will always stay above the Relative Layout - even when the Edittext expands.
Here's the XML.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.CoordinatorLayout
android:id="#+id/data_coordinator_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_above="#+id/delete_data_layout"> <---- Change here
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</android.support.design.widget.CoordinatorLayout>
<RelativeLayout
android:id="#+id/delete_data_layout"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentBottom="true"> <---- Change here
<EditText/>
<Button/>
<Button/>
<Button/>
</RelativeLayout>
</RelativeLayout>