Develop Reference

Android Studio: Buttons in Grid Layout change size in emulator

enter image description here
I don't know how to make all button sizes the same... I tried making grid to wrap content, it worked, but button sizes were a bit different depending on the number of characters. Does anyone know how to format this stuff?
I tried adding number of rows and columns, gravity, etc, but it didn't change a thing.
Here is my XML code:
<GridLayout
android:layout_height="match_parent"
android:layout_width="match_parent">
<Button
android:text="Hello"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="0"
android:layout_row="0"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/hello"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="Do you speak
English?"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="1"
android:layout_row="0"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/english"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="Good Evening"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="0"
android:layout_row="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/goodEvening"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="Please"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="1"
android:layout_row="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/please"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="My name is"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="0"
android:layout_row="2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/name"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="Welcome"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="1"
android:layout_row="2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/welcome"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="How are you?"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="0"
android:layout_row="3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/howAreYou"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
<Button
android:text="I live in"
android:layout_rowWeight="1"
android:layout_columnWeight="1"
android:layout_column="1"
android:layout_row="3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/iLiveIn"
android:onClick="buttonTapped"
android:gravity="center"
android:layout_gravity="fill" />
</GridLayout>

As you can see in this document . android:layout_gravity="fill" will
Grow the horizontal and vertical size of the object if needed so it
completely fills its container
and here your container size is match_parent.So it is filling your layout . Now make your container(GridLayout) wrap_content , otherwise use gravity attribute properly

Change from match_parent to wrap_content if you plan on using GridLayout:
<GridLayout
android:layout_height="wrap_content"
android:layout_width="wrap_content">
</GridLayout>
If not, then use constrain guidelines or linearlayout

gridlayout: centering image in imageview

i want that the image fits in the imageview at the gridlayout. When i dont give a source to the imageview the layout is correct. But when i put the source there the width and height of the imageview is wrong. Can somebody help me to solve the problem? I this for a game.
Correct Layout without src
XML without src
<?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="com.ktappworks.test.MainActivity">
<GridLayout
android:id="#+id/ph0"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_marginTop="0dp"
android:clipChildren="false"
android:columnCount="5"
android:rowCount="2"
android:src="#mipmap/ic_launcher"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginRight="8dp"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_marginBottom="8dp"
android:layout_marginLeft="8dp"
app:layout_constraintLeft_toLeftOf="parent">
<ImageView
android:id="#+id/ph00"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph01"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph02"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph03"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph04"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph05"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph06"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph07"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph08"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
<ImageView
android:id="#+id/ph09"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
/>
</GridLayout>
</android.support.constraint.ConstraintLayout>
Incorrect layout with src
XML with src
<?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="com.ktappworks.test.MainActivity">
<GridLayout
android:id="#+id/ph0"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_marginTop="0dp"
android:clipChildren="false"
android:columnCount="5"
android:rowCount="2"
android:src="#mipmap/ic_launcher"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginRight="8dp"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_marginBottom="8dp"
android:layout_marginLeft="8dp"
app:layout_constraintLeft_toLeftOf="parent">
<ImageView
android:id="#+id/ph00"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph01"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph02"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph03"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph04"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph05"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph06"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph07"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph08"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
<ImageView
android:id="#+id/ph09"
android:layout_columnWeight="1"
android:layout_margin="2dp"
android:layout_rowWeight="1"
android:scaleType="fitXY"
android:src="#drawable/owl" />
</GridLayout>
</android.support.constraint.ConstraintLayout>
Owl Image

You need to define the width and height of each ImageView as 0dp for the column/row weights to take effect. I think the default is wrap_content. You may also want to change the scaleType to something other than fitXY since fitXY will distort the images.
I have also run into an issue with the native implementation of GridLayout when using the weights for certain API levels. (I answered such a question recently and I will post a reference to it here if I can find it.) You may want to think about using the support library version of GridLayout since it seems to have a working implementation of weights. Add the following to your gradle file for this version of GridLayout:
compile 'com.android.support:gridlayout-v7:26.1.0'
Here is a screen shot after making these changes:

How to center image buttons inside of a Grid Layout - Android Studio

I have looked at various solutions, including gravity, but have not found the answer to the problem that I am having, which is that the image buttons inside of the grid layout are not spanning the width of the screen - looking like this picture below. They are more clumped up towards the left. I would like the spacing to be even across the screen. Thanks for the help.
Here is the XML file:
<?xml version="1.0" encoding="utf-8"?>
<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:id="#+id/activity_admin_control"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.myname.myproject.AdminControl">
<Button
android:text="Switch to User"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_centerHorizontal="true"
android:layout_gravity="center"
android:id="#+id/userSwitch" />
<GridLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/userSwitch"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:rowCount="2"
android:columnCount="3"
android:alignmentMode="alignMargins">
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:layout_row="0"
android:layout_column="0"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton5"
android:layout_row="0"
android:layout_column="1"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton6"
android:layout_row="0"
android:layout_column="2"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton7"
android:layout_row="1"
android:layout_column="0"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton8"
android:layout_row="1"
android:layout_column="1"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton9"
android:layout_row="1"
android:layout_column="2"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
</GridLayout>
</RelativeLayout>

Don't define width yourself. Let GridLayout do this task. Set all width and height to 0dp and all weights to 1.
This might work for you. I didn't check it, but it should work.
<GridLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/userSwitch"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:rowCount="2"
android:columnCount="3"
android:alignmentMode="alignMargins">
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:layout_row="0"
android:layout_column="0"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton5"
android:layout_row="0"
android:layout_column="1"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton6"
android:layout_row="0"
android:layout_column="2"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton7"
android:layout_row="1"
android:layout_column="0"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton8"
android:layout_row="1"
android:layout_column="1"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton9"
android:layout_row="1"
android:layout_column="2"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:scaleType="fitCenter"/>
</GridLayout>

Try this,
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/activity_admin_control"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:id="#+id/userSwitch"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_gravity="center"
android:text="Switch to User" />
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_above="#+id/userSwitch"
android:layout_centerHorizontal="true">
<GridLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_centerHorizontal="true"
android:alignmentMode="alignMargins"
android:columnCount="3"
android:rowCount="2">
<ImageButton
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="0"
android:layout_row="0"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
<ImageButton
android:id="#+id/imageButton5"
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="1"
android:layout_row="0"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
<ImageButton
android:id="#+id/imageButton6"
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="2"
android:layout_row="0"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
<ImageButton
android:id="#+id/imageButton7"
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="0"
android:layout_row="1"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
<ImageButton
android:id="#+id/imageButton8"
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="1"
android:layout_row="1"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
<ImageButton
android:id="#+id/imageButton9"
android:layout_width="118dp"
android:layout_height="118dp"
android:layout_column="2"
android:layout_row="1"
android:scaleType="fitCenter"
app:srcCompat="#drawable/common_google_signin_btn_icon_dark" />
</GridLayout>
</RelativeLayout>
</RelativeLayout>

I find out that it's not possible to center GridView horizontally with .xml
So I had to do it programmatically... This answer helped me a lot:
link

you can try this width and height is harcoded you need to fix either row or column or you can use margin.
<?xml version="1.0" encoding="utf-8"?>
<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:id="#+id/activity_admin_control"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.myname.myproject.AdminControl">
<Button
android:text="Switch to User"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_centerHorizontal="true"
android:layout_gravity="center"
android:id="#+id/userSwitch" />
<GridLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/userSwitch"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_marginLeft="#dimen/activity_vertical_margin"
android:layout_marginRight="#dimen/activity_vertical_margin"
android:rowCount="2"
android:columnCount="3"
android:alignmentMode="alignMargins">
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:layout_row="0"
android:layout_column="0"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton5"
android:layout_row="0"
android:layout_column="1"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton6"
android:layout_row="0"
android:layout_column="2"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton7"
android:layout_row="1"
android:layout_column="0"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton8"
android:layout_row="1"
android:layout_column="1"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
<ImageButton
app:srcCompat="#drawable/common_google_signin_btn_icon_dark"
android:id="#+id/imageButton9"
android:layout_row="1"
android:layout_column="2"
android:layout_width="118dp"
android:layout_height="118dp"
android:scaleType="fitCenter"/>
</GridLayout>
</RelativeLayout>

XML Error "Grid Layout is Useless" (Android Studio)

I'm currently taking an Android Development course in Udemy, and I'm currently learning how to build a basic phrases app, which consists of a Grid Layout. I followed exactly what the instructor did with the XML part, and I got an error that the instructor didn't get:
This GridLayout layout or its RelativeLayout parent is useless. A layout with children that has no siblings, is not a scrollview or a root layout, and does not have a background, can be removed and have its children moved directly into the parent for a flatter and more efficient layout hierarchy.
This is the XML:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.jumin.basicphrases.MainActivity">
<GridLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Hello"
android:onClick="buttonTapped"
android:id="#+id/button" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="How are you?"
android:onClick="buttonTapped"
android:id="#+id/howareyou" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Good Evening"
android:onClick="buttonTapped"
android:id="#+id/goodevening" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Please"
android:onClick="buttonTapped"
android:id="#+id/please" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="My name is..."
android:onClick="buttonTapped"
android:id="#+id/mynameis" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Do you
speak English?"
android:onClick="buttonTapped"
android:id="#+id/doyouspeakenglish" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Welcome"
android:onClick="buttonTapped"
android:id="#+id/welcome" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="I live in..."
android:onClick="buttonTapped"
android:id="#+id/ilivein" />
</GridLayout>
</RelativeLayout>

The error is very clear: Just remove the RelativeLayout and try again:
<GridLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Hello"
android:onClick="buttonTapped"
android:id="#+id/button" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="How are you?"
android:onClick="buttonTapped"
android:id="#+id/howareyou" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Good Evening"
android:onClick="buttonTapped"
android:id="#+id/goodevening" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Please"
android:onClick="buttonTapped"
android:id="#+id/please" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="My name is..."
android:onClick="buttonTapped"
android:id="#+id/mynameis" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Do you
speak English?"
android:onClick="buttonTapped"
android:id="#+id/doyouspeakenglish" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Welcome"
android:onClick="buttonTapped"
android:id="#+id/welcome" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="I live in..."
android:onClick="buttonTapped"
android:id="#+id/ilivein" />
</GridLayout>

This warning is because your RelativeLayout contains only GridLayout and both (recyclerView and GridLayout) are set to match_parent
You can remove RelativeLayout and set GridLayout as root layout and it will look exactly like now but better for performance.
<?xml version="1.0" encoding="utf-8"?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.jumin.basicphrases.MainActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Hello"
android:onClick="buttonTapped"
android:id="#+id/button" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="0"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="How are you?"
android:onClick="buttonTapped"
android:id="#+id/howareyou" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Good Evening"
android:onClick="buttonTapped"
android:id="#+id/goodevening" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="1"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Please"
android:onClick="buttonTapped"
android:id="#+id/please" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="My name is..."
android:onClick="buttonTapped"
android:id="#+id/mynameis" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="2"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Do you
speak English?"
android:onClick="buttonTapped"
android:id="#+id/doyouspeakenglish" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="Welcome"
android:onClick="buttonTapped"
android:id="#+id/welcome" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_row="3"
android:layout_columnWeight="1"
android:layout_rowWeight="1"
android:layout_gravity="fill"
android:text="I live in..."
android:onClick="buttonTapped"
android:id="#+id/ilivein" />
</GridLayout>

GridLayout not filling rows evenly (Android)

I'm trying to get an evenly filled grid using GridLayout (API 21). Filling in the horizontal direction works fine using layout_columnWeight attribute. The same with layout_rowWeight attribute fails (see screenshot) . I am pretty clueless.. It seems like the both attributes don't work in the same way.
Also even more simplified layouts show the same behavior (1 row x 2 columns works, 2 rows x 1 column fails). Also explicitly adding of layout_row and layout_column attributes don't change anything.
Please don't answer "use linearLayout". I want to get it working with the GridLayout.
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#0099cc"
tools:context=".Locomotion">
<GridLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:columnCount="2"
android:rowCount="2">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="north west"
android:id="#+id/textViewNW"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="center|fill"
android:background="#fe4141" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="north east"
android:id="#+id/textViewNE"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="center|fill"
android:background="#51f328" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="south west"
android:id="#+id/textViewSW"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="center|fill"
android:background="#fefe00" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="south east"
android:id="#+id/textViewSE"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="center|fill"
android:background="#0080f0" />
</GridLayout>
</FrameLayout>
Thanks in advance for any hint!
Thomas

This was difficult. Had to get creative to solve it. Basically my solution was to nest GridLayouts for each col with a master GridLayout for 1 row. Also each col GridLayout must be in orientation="verticle" with width/height = "wrap_content"
Result:
Here's the code:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#0099cc"
tools:context=".Locomotion">
<GridLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:columnCount="2"
android:rowCount="1">
<GridLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:columnCount="1"
android:rowCount="2"
android:layout_column="0"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:orientation="vertical">
<TextView
android:id="#+id/textViewNW"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_row="0"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:background="#fe4141"
android:text="north west"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/textViewSW"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_row="1"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:background="#fefe00"
android:text="south west"
android:textAppearance="?android:attr/textAppearanceLarge" />
</GridLayout>
<GridLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:columnCount="1"
android:rowCount="2"
android:layout_column="1"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:orientation="vertical">
<TextView
android:id="#+id/textViewNE"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_row="0"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:background="#51f328"
android:text="north east"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/textViewSE"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_columnSpan="1"
android:layout_columnWeight="1"
android:layout_gravity="fill"
android:layout_row="1"
android:layout_rowSpan="1"
android:layout_rowWeight="1"
android:background="#0080f0"
android:text="south east"
android:textAppearance="?android:attr/textAppearanceLarge" />
</GridLayout>
</GridLayout>
</FrameLayout>