I want to place my horizonatl recyclerview at 30% screen width from start
<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">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:clipToPadding="false"
android:orientation="horizontal"
android:paddingStart="20dp"
android:paddingEnd="20dp"
android:background="#android:color/white"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/guideline" />
<android.support.constraint.Guideline
android:id="#+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.3" />
</android.support.constraint.ConstraintLayout>
But it is not recyclerview not appearing on screen working any idea how to achieve this.
You never gave your recyclerView a vertical constraint so what happened is that at the run time your recyclerView just jumped to the top of the screen.
When I copied your code I saw this error:
This view is not constrained vertically: at runtime, it will jump to the top unless you add a vertical constraint
Some tip - if you see the red line on your view in the XML/the red warning button from the design you should really look at the error and change your layout accordingly.
And of course, I won't leave you without a good working layout - here is the layout that I made for the recyclerView to start at 30% of the screen, I have checked it and its working. (i was working with androidx but just change it to the support library if you want)
<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">
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.3"/>
<androidx.recyclerview.widget.RecyclerView
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="16dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.506"
app:layout_constraintStart_toStartOf="#+id/guideline2"
app:layout_constraintTop_toTopOf="parent"
android:background="#color/colorPrimaryDark"/>
your RecyclerView is missing the vertical constraints; Add at least one so that the view can be rendered.
constrained to top:
app:layout_constraintTop_toTopOf="parent"
if you want it to use the whole parent, add these too:
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
Remove the ConstraintLayout and use Linearlayout instead, than use the android:weight= property accordingly in both guideline and RecyclerView.
This will work fine for you
<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">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="0dp"
android:layout_height="0dp"
android:clipToPadding="false"
android:orientation="horizontal"
android:paddingStart="20dp"
android:paddingEnd="20dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="#id/guideline"
app:layout_constraintBottom_toBottomOf="parent"
/>
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent=".3" />
</android.support.constraint.ConstraintLayout>
Related
I have something 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:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp"
tools:context=".ui.base.core.example">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="hello" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/topicsRecyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:listitem="#layout/item_topics" />
</androidx.constraintlayout.widget.ConstraintLayout>
When I run this, the TextView element is fixed and scrolls when I scroll through my RecyclerView. Is there a way so that I can make it where the TextView element is on top of the RecyclerView and when I scroll it's not fixed? I'm using a TextView to just do testing, but eventually I'd like to have a header on top of the RecyclerView that shouldn't be scrollable with the RecyclerView and just stay on top.
You need to set up constraints.
Approximately like this:
<TextView
android:id="#+id/textView"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="#id/topicsRecyclerView" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/topicsRecyclerView"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="#id/textView"
app:layout_constraintBottom_toBottomOf="parent" />
Is there a way, using ConstraintLayout to achieve the below, without setting an invisible View on the right side as well? (The right back arrow should be invisible, I've made it visible to make things easier to understand)
The middle view currently is as follows:
<RelativeLayout
android:id="#+id/cover_wrapper"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="#dimen/_10sdp"
android:onClick="#{(view) -> viewModel.onAutoPlayButtonClick()}"
app:layout_constraintStart_toEndOf="#id/back_button"
app:layout_constraintEnd_toStartOf="#id/dummy_button"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="#id/buttons_wrapper"
app:layout_constraintDimensionRatio="3:4">
Besides simply setting a right margin calculated as button_width + button_margin_left + button_margin_right, is there a trick to not have the right View there and not use margins either?
Yes you can achieve that using ConstraintLayout and Guidelines without setting any invisible View
<?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"
android:background="#color/grey"
>
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="30dp"
app:layout_constraintEnd_toStartOf="#+id/guideline2"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:tint="#color/green"
android:background="#color/white"
android:padding="10dp"
app:srcCompat="?attr/actionModeCloseDrawable" />
<View
android:layout_width="0dp"
android:layout_height="200dp"
app:layout_constraintStart_toStartOf="#+id/guideline2"
app:layout_constraintEnd_toEndOf="#id/guideline3"
app:layout_constraintTop_toTopOf="#id/imageView"
/>
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent=".3" />
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent=".7" />
</androidx.constraintlayout.widget.ConstraintLayout>
Hey I am working in constraint layout with recylerview. My bottom item is cut in the screen. I read this stack overflow post. I don't want to use relative layout or linear layout. Can someone guide me how to fix this in constraint layout.
abc.xml
<?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">
<androidx.appcompat.widget.SearchView
android:id="#+id/searchView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="16dp"
app:closeIcon="#drawable/ic_cancel"
app:layout_constraintBottom_toTopOf="#+id/exploreScroll"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_chainStyle="packed"
app:layout_constraintVertical_bias="0.0" />
<HorizontalScrollView
android:id="#+id/exploreScroll"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginTop="10dp"
android:scrollbars="none"
app:layout_constraintBottom_toTopOf="#+id/exploreList"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/searchView">
<com.google.android.material.chip.ChipGroup
android:id="#+id/exploreChips"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipSpacingHorizontal="10dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:singleLine="true"
app:singleSelection="true" />
</HorizontalScrollView>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/exploreList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:paddingTop="10dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/exploreScroll" />
</androidx.constraintlayout.widget.ConstraintLayout>
My view cut from
UPDATE
#Zain after your suggestion i tried in my xml any my HorizontalScrollView is going behind my RV. I am adding my blueprint and you can see clearly that, HorizontalScrollView is going behind. After removing app:layout_constraintBottom_toTopOf="#+id/exploreList" from the HorizontalScrollView.
2nd suggestion try
Disclaimer Using a wrap_content height with vertical RecyclerView
can have impact on performance in terms of recycling views; specially
if the height is going to change frequently. Check this article
for more illustration.
So, the first step is to designate the RecyclerView height or to constraint it; from the constraints you want it to expand to the bottom; so use 0dp for that. But in order to make the minimum height to wrap content of the RecyclerView (in case that the items don't exceed the screen height); you can set the default height constraint to wrap with app:layout_constraintHeight_default="wrap" constraint.
Then remove app:layout_constraintBottom_toTopOf="#+id/exploreList" from the HorizontalScrollView, this actually made the bottom item of the RV hide (your main issue); because it is an over-constraint; the HorizontalScrollView tends to push the RV to the bottom while the RV tends to push the HorizontalScrollView to the top.
This will solve the main issue; but when the items are fully accommodated by the screen (no scrolling in the RV), then it will be biased in the middle; to fix this use the bias with app:layout_constraintVertical_bias="0.0" to be biased to the top.
Adding this in place into the layout:
<?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">
<androidx.appcompat.widget.SearchView
android:id="#+id/searchView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="16dp"
app:closeIcon="#drawable/ic_cancel"
app:layout_constraintBottom_toTopOf="#+id/exploreScroll"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0"
app:layout_constraintVertical_chainStyle="packed" />
<HorizontalScrollView
android:id="#+id/exploreScroll"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginTop="10dp"
android:scrollbars="none"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/searchView">
<com.google.android.material.chip.ChipGroup
android:id="#+id/exploreChips"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipSpacingHorizontal="10dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:singleLine="true"
app:singleSelection="true" />
</HorizontalScrollView>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/exploreList"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginBottom="20dp"
android:paddingTop="10dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHeight_default="wrap"
app:layout_constraintVertical_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/exploreScroll" />
</androidx.constraintlayout.widget.ConstraintLayout>
I am using constraint layout with a vertical bias to fill view in recycler view. I successfully did that.
<?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"
android:background="#color/white">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recylerview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingStart="10dp"
android:paddingEnd="10dp"
android:paddingBottom="10dp"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0" />
</androidx.constraintlayout.widget.ConstraintLayout>
My recyclerview items showing me in reverse order because I want to make chat application. So I added reverseLayout and stackFromEnd true. So it look like this.
If my item is single my ui convert into like this by above xml code
Now I want to add edittext and button in bottom. Its not working vertical bias. Does any one know how to fix. Any suggestion to what can i use
Expected Output
Scenerio 1
Scenerio 2
Actual Output
I tried this code
<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"
android:background="#color/white">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingStart=10dp"
android:paddingEnd="10dp"
android:paddingBottom="10dp"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_constraintBottom_toTopOf="#+id/inputContainer"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0" />
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/inputContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingBottom="20dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/crecyclerView">
<EditText
android:id="#+id/editTextContainer"
android:layout_width="200dp"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/editTextContainer"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
UPDATE
After adding #MartinMarconcini answer it fixed my Scenario 2. I want to fix as Scenario 1 as well.
The idea is that your RV will handle its own item size and space by itself. You don't need to worry about this.
The Remainder of the space, will be used by ConstraintLayout.
So you need to pin the RV and the "Bottom Container" together. This would by default cause the CL to try to pull and balance layouts, so you have to tell the bottom container to be biased at the bottom.
In pseudo-XML:
<ConstraintLayout>
<RecyclerView
width=0dp
height=0dp
start/end = parent
TopToTop=parent
BottomToTopOf=BottomContainer
>
<BottomContainer>
width=0dp
height=wrap_content
TopToBottomOf=RecyclerView
BottomToBottomOf=parent
start/end = parent>
</ConstraintLayout>
Now this needs one more thing, because the RV would take all the space, you want to ensure the BottomContainer has more information about where it wants to be placed.
So you add:
app:layout_constraintVertical_bias="1.0"
to the Bottom Container.
This means, vertically, as "bottom" as you can. (0.0 would be the opposite).
The end result is:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recylerview"
android:layout_width="0dp"
android:layout_height="0dp"
android:paddingStart="10dp"
android:paddingEnd="10dp"
android:paddingBottom="10dp"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:listitem="#android:layout/simple_list_item_2" />
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="0dp"
app:layout_constraintVertical_bias="1.0"
android:layout_height="wrap_content"
android:id="#+id/bottomContainer"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="#id/recylerview"
app:layout_constraintBottom_toBottomOf="parent">
<EditText
android:id="#+id/editTextContainer"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/editTextContainer"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
Which looks like this:
UPDATE
If you add both
app:stackFromEnd="true"
app:reverseLayout="true"
It works the same way, except the item "0" is at the bottom, and the "last" item is at the top. Adding another item would add it at the top but the BottomContainer has no participation (or influence) over this:
My problem is that the controls (checkboxes, buttons etc) which I have placed are not visible on my emulator.
Below is my XML file:
<?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"
tools:context=".MainActivity">
<Button
android:id="#+id/btn1"
android:layout_width="match_parent"
android:layout_height="52dp"
android:text="#string/btn1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="MissingConstraints"
tools:layout_editor_absoluteY="0dp" />
<Button
android:id="#+id/btn2"
android:layout_width="match_parent"
android:layout_height="77dp"
android:text="#string/btn2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="MissingConstraints"
tools:layout_editor_absoluteY="68dp" />
<fragment
android:id="#+id/fragment"
android:name="com.example.mypc.fragmentactivity.Fragment1"
android:layout_width="222dp"
android:layout_height="285dp"
android:layout_marginBottom="40dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:ignore="MissingConstraints" />
Here is my XML (design view):
Here is my emulator window:
Is there is something wrong in my XML file?
Please provide me solution for this.
How should I handle this?
You are using ConstraintLayout without relative positioning.
According to developer site:
Relative positioning is one of the basic building blocks of creating layouts in ConstraintLayout. Those constraints allow you to position a given widget relative to other. You can constrain a widget on the horizontal and vertical axis:
Horizontal Axis: left, right, start and end sides
Vertical Axis: top, bottom sides, and text baseline
Here is the solution which may help you:
<?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"
tools:context=".MainActivity">
<Button
android:id="#+id/btn1"
android:layout_width="match_parent"
android:layout_height="52dp"
android:text="#string/btn1"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="#id/btn2"/>
<Button
android:id="#+id/btn2"
android:layout_width="match_parent"
android:layout_height="77dp"
android:text="#string/btn2"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#id/btn1"
android:layout_marginTop="10dp"/>
</android.support.constraint.ConstraintLayout>
I have used relative positioning to solve the problem. If you are using constraint layout then without relative positioning your views will get overlap with each other.
Because you didn't align properly the second button. it seems like second button overlap first one.
try this one
<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"
tools:context=".activites.HomeActivity"
android:layout_margin="6dp">
<Button
android:id="#+id/btnOne"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="Button One"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/btnTwo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="Button Two"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/btnOne" />
<fragment
android:id="#+id/fragment"
android:layout_width="222dp"
android:layout_height="285dp"
android:layout_marginBottom="40dp"
android:layout_marginTop="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/btnTwo"
tools:ignore="MissingConstraints" />
</android.support.constraint.ConstraintLayout>
output would be like this
In your code your elements are overflowing each other at one position that is why they are not visible.
My suggestion is do not constraint Layout at initial stage of learning android.
Use Linear Layout in place of constraint Layout.
Since in constraint Layout Layout Editor uses constraints to determine the position of a UI element within the layout. You have to give many constraint XML attributes like.
app:layout_editor_absoluteX="73dp"
app:layout_editor_absoluteY="176dp"
app:layout_constraintLeft_creator="1"
app:layout_constraintTop_creator="1"
app:layout_constraintRight_creator="1"
to specify the position of elements in layout.
Use Linear Layout in place of Constraint Layout and give
orientation:"vetical"
to view all your elements.
The layout_editor attributes are only used for the editor preview and have no effect on the final layouts. You should position your elements using the ConstraintLayout specific attributes.
It's used to just for preview purpose.
tools:layout_editor_absoluteY="68dp"
Simply use LinearLayout instead of ConstraintLayout. Also provide orientation vertical to that LinearLayout.
It will helps you
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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=".MainActivity">
<Button
android:id="#+id/btn1"
android:layout_width="match_parent"
android:layout_height="52dp"
android:text="#string/btn1" />
<Button
android:id="#+id/btn2"
android:layout_width="match_parent"
android:layout_height="77dp"
android:text="#string/btn2" />
<fragment
android:id="#+id/fragment"
android:name="com.example.mypc.fragmentactivity.Fragment1"
android:layout_width="222dp"
android:layout_height="285dp"
android:layout_marginBottom="40dp" />
</LinearLayout>