Develop Reference

Android TextView Left Gravity Problem in an Item XML for RecyclerView

I have an RecyclerViewAdapter and I'm preparing an item xml to display my all items as list.
I've written my xml like this:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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/constraintLayoutAutoCompleteTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:background="#drawable/bg_film_add_recycler_view">
<TextView
android:id="#+id/textViewFilmName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="false"
android:textSize="16sp"
android:textColor="#color/figma_text_color_dark"
android:fontFamily="#font/inter500_regular"
app:layout_constraintBottom_toBottomOf="#id/imageViewFilmLogo"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/imageViewFilmLogo"
app:layout_constraintTop_toTopOf="#id/imageViewFilmLogo"
tools:text="MyFilm">
</TextView>
<ImageView
android:id="#+id/imageViewFilmLogo"
android:layout_width="80dp"
android:layout_height="30dp"
android:layout_marginStart="30dp"
android:layout_marginVertical="10dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent">
</ImageView>
</androidx.constraintlayout.widget.ConstraintLayout>
As result of this, I see my RecyclerView like this (red ones are textviews, green ones are imageviews):
As you see, the textviews looks like centered in specific area. But I want aligned to left like this:
I tried to add android:gravity="left" but it doesn't work, what is the problem? can you help me please?
If possible, can you equilaze the distances between "left edge of layout - imageview" and "imageview - left edge of textview"

Use 0dp for views if you wish to set behavior of view like layout_gravity="start" in constraintLayout
And don't forget add margin start for second element
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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/constraintLayoutAutoCompleteTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:background="#drawable/bg_film_add_recycler_view">
<TextView
android:id="#+id/textViewFilmName"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:clickable="false"
android:textSize="16sp"
android:textColor="#color/figma_text_color_dark"
android:fontFamily="#font/inter500_regular"
app:layout_constraintBottom_toBottomOf="#id/imageViewFilmLogo"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/imageViewFilmLogo"
app:layout_constraintTop_toTopOf="#id/imageViewFilmLogo"
tools:text="MyFilm">
</TextView>
<ImageView
android:id="#+id/imageViewFilmLogo"
android:layout_width="80dp"
android:layout_height="30dp"
android:layout_marginStart="30dp"
android:layout_marginVertical="10dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent">
</ImageView>
</androidx.constraintlayout.widget.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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/constraintLayoutAutoCompleteTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:background="#drawable/bg_film_add_recycler_view">
<ImageView
android:id="#+id/imageViewFilmLogo"
android:layout_width="80dp"
android:layout_height="30dp"
android:layout_marginStart="30dp"
android:layout_marginVertical="10dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
tools:ignore="ContentDescription">
</ImageView>
<LinearLayout
android:id="#+id/textViewFilmName_container"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintBottom_toBottomOf="#id/imageViewFilmLogo"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/imageViewFilmLogo"
app:layout_constraintTop_toTopOf="#id/imageViewFilmLogo"
android:paddingStart="30dp">
<TextView
android:id="#+id/textViewFilmName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="false"
android:textSize="16sp"
android:textColor="#color/figma_text_color_dark"
android:fontFamily="#font/inter500_regular"
tools:text="MyFilm">
</TextView>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

Button not visible in AVD

Making an app. Last 2 button are visible in preview mode , but not in AVD(Google pixel 3a). Actually I'm new to Android. I just directly pasted the code if need more information let me know. Thank you
Snippet of code
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
tools:context=".MainActivity">
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="#string/courses_offered"
android:layout_marginTop="470dp"
android:layout_marginBottom="140dp"
android:layout_marginRight="30dp"
android:layout_marginLeft="230dp"
android:textColor="#color/white"
android:backgroundTint="#color/orange"
/>
<Button
android:id="#+id/Fee_structure"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="#string/fee_structure"
android:layout_marginTop="470dp"
android:layout_marginBottom="140dp"
android:layout_marginRight="230dp"
android:layout_marginLeft="30dp"
android:textColor="#color/white"
android:backgroundTint="#color/orange"
/>
</androidx.constraintlayout.widget.ConstraintLayout>

You're using ConstraintLayout but your buttons doesn't have any constraint to initialize where they should be
For example:
adding app:layout_constraintBottom_toBottomOf="parent" will position the bottom of the button to the bottom of parent, in this case, your layout
See this for further details and examples: https://developer.android.com/reference/androidx/constraintlayout/widget/ConstraintLayout?authuser=1

You have to use constraints in the Constraint layout just like
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
enter link description here
Try this code it will show you in AVD.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:backgroundTint="#color/teal_200"
android:text="asd"
android:textColor="#color/white"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.8"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.8" />
<Button
android:id="#+id/Fee_structure"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:backgroundTint="#color/teal_200"
android:text="asd"
android:textColor="#color/white"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintHorizontal_bias="0.2"
app:layout_constraintVertical_bias="0.8" />
</androidx.constraintlayout.widget.ConstraintLayout>

You have given height and width to match parent so your first button is taking all the space available in screen so you have to make them wrap content (height) and then constraint them accordingly

Android Activity_Main Float Button

This is Acitivity_main.xml of a PDF Reader on Android.
I am confused on how to add two floating Action Buttons(Page Up/Down Button) in the bottom right corner. The buttons need to display above PDF, and uses linear vertical layout.
Following XML separates PDF and Buttons into two parts which is wrong, any idea how to correct it?
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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"
tools:context=".MainActivity">
<LinearLayout
android:id="#+id/pdfstructure"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentBottom="true"
android:orientation="vertical"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/DownButton"
android:layout_width="100dp"
android:layout_height="200dp"
android:layout_gravity="end|bottom"
android:layout_marginTop="600dp"
android:layout_marginRight="30dp"
android:clickable="true"
android:contentDescription="#string/upButton"
android:stateListAnimator="#null"
android:text="Down"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/upButton"
android:layout_width="100dp"
android:layout_height="200dp"
android:layout_gravity="end|bottom"
android:layout_marginTop="800dp"
android:layout_marginRight="30dp"
android:clickable="true"
android:text="Up"
android:stateListAnimator="#null"
android:contentDescription="#string/upButton"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

Add this line in your linearLayout
android:gravity="bottom"
and delete those lines in your FloatingActionButton
android:layout_marginTop="600dp"
android:layout_marginTop="800dp"

Place ImageView on top of button in ConstraintLayout

I'm facing issues with constraintlayout when placing ImageView or FrameLayout on top of a Button.
When i try to inflate a fragment on FrameLayout, Buttons that are part of activity are visible on top of fragment UI.
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"/>
<FrameLayout
android:background="#color/blue"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
</android.support.constraint.ConstraintLayout>

To place any view above another view you have to give proper constraint like below.
Give top and bottom constraint proper and also as I give all constraint(start,end,top,bottom) to FrameLayout it's height and width give to 0dp(you can't use height to match_parent otherwise it's cover whole screen and overlap button).
>
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent" android:layout_height="match_parent">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintBottom_toBottomOf="parent"/>
<FrameLayout
android:background="#color/colorPrimary"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="#+id/button"/>
</android.support.constraint.ConstraintLayout>

To set constraints of button and FrameLayout to,
Button:
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
FrameLayout :
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/button"

Your code looks ok but if you want to tell 1 view to be above another view in ConstraintLayout you can go to the design tab and move the higher above the lower view:
Example:
In the image, you can see that the button is placed below the frameLayout so he will be lower than the frameLayout (the frameLayout will be above the button)
Also, you were missing some constraints on your button :
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="#+id/frameLayout2" />
<FrameLayout
android:id="#+id/frameLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
And if all that didn't help you check this thread, as #Xavier Rubio Jansana said, it may be because of elevation.

Try the code below
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
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">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:text="button"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="638dp"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:layout_marginBottom="8dp"
android:background="#color/appGrey"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/button">
</FrameLayout>
</android.support.constraint.ConstraintLayout>

How to put text on right centre of image view on constraint layout

Following is a part of my whole xml of constraint Layout.
<ImageView
android:id="#+id/img_apn_not_set"
style="#style/DeviceManagementImageView"
android:contentDescription="#string/app_name"
android:src="#drawable/ic_sos"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/view1" />
<TextView
android:id="#+id/tv_apn_not_set"
style="#style/DeviceManagementHeaderText"
android:text="Apn not set"
android:layout_marginTop="5dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/img_apn_not_set"
app:layout_constraintTop_toTopOf="#+id/img_apn_not_set" />
What I am trying to do is get the text view on exact centre on the right side of image view. In linear layout we achieve it mostly by gravity. Here I am using marginTop to achieve the same . So can I do the same by using any property . Is there a property something like rightOfCentreOf ?
Thanks

pls add one line in your textview
app:layout_constraintBottom_toBottomOf="#+id/img_apn_not_set"
also remove android:layout_marginTop="5dp"
hope it help you

Try this, If you want to move the text to the right or left use Horizontal bias, If you want to move your text to the top or bottom use vertical bias.
<TextView
android:id="#+id/tv_apn_not_set"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="#string/app_name"
app:layout_constraintBottom_toBottomOf="#+id/img_apn_not_set"
app:layout_constraintEnd_toEndOf="#+id/img_apn_not_set"
app:layout_constraintHorizontal_bias="0.63"
app:layout_constraintStart_toStartOf="#+id/img_apn_not_set"
app:layout_constraintTop_toTopOf="#+id/img_apn_not_set" />

Try this
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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">
<ImageView
android:id="#+id/AmountLabel"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_launcher_background"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintBaseline_toBaselineOf="#id/Amount"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/Amount"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="40dp"
android:text="NILESH"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toEndOf="#id/AmountLabel"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
RESULT

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="#+id/img_apn_not_set"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#mipmap/ic_launcher"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/tv_apn_not_set"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Apn not set"
app:layout_constraintBottom_toBottomOf="#+id/img_apn_not_set"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/img_apn_not_set"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

You can use app:layout_constraintWidth_default="wrap" and give all 4 side constraint it will be at center
Example:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="#+id/img_apn_not_set"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="#string/app_name"
android:src="#drawable/ic_launcher_foreground"
app:layout_constraintLeft_toLeftOf="parent" />
<TextView
android:id="#+id/tv_apn_not_set"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Apn not set"
app:layout_constraintWidth_default="wrap"
app:layout_constraintTop_toTopOf="#+id/img_apn_not_set"
app:layout_constraintBottom_toBottomOf="#+id/img_apn_not_set"
app:layout_constraintLeft_toRightOf="#+id/img_apn_not_set"
app:layout_constraintRight_toRightOf="parent" />
</android.support.constraint.ConstraintLayout>
It will look like this