Develop Reference

Android Spinner has a bigger height when an option is selected

In my layout I have 6 spinners that are not necessaritly displayed.
When no option is selected, the height is good, but when an option is selected, it looks bigger and I didn't find anything about that online.
Here is the spinners without an option selected
And when an option is selected
Here is the Layout which contains the spinners:
<LinearLayout
android:id="#+id/layoutDetail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:gravity="center"
android:orientation="vertical"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/details">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="horizontal"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent">
<TextView
android:id="#+id/txtDetail1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/black"
android:textSize="#dimen/medium_text"/>
<Spinner
android:id="#+id/spinDetail1"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="#drawable/spinner"/>
</LinearLayout>
... Same thing 5 more times ...
</LinearLayout>
And here is my java code for the spinners:
private void initializeDetails() {
List<Detail> details = mainAct.details;
detailSpinners = new Spinner[details.size()];
int marginTop = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 16, getResources().getDisplayMetrics());
int marginEnd = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, getResources().getDisplayMetrics());
int marginStart = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 8, getResources().getDisplayMetrics());
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT);
params.gravity = Gravity.TOP;
for (int i = 0; i < details.size(); i++) {
int tvID = getResources().getIdentifier("txtDetail" + (i + 1), "id", mainAct.getPackageName());
int spinID = getResources().getIdentifier("spinDetail" + (i + 1), "id", mainAct.getPackageName());
TextView txtDetail = inputView.findViewById(tvID);
Spinner spinDetail = inputView.findViewById(spinID);
txtDetail.setText(details.get(i).getTitle());
List<String> answers = details.get(i).getAnswers();
answers.add("");
final int answersSize = answers.size() - 1;
ArrayAdapter<String> detailAdapter = new ArrayAdapter<String>(mainAct, R.layout.support_simple_spinner_dropdown_item, answers) {
#Override
public int getCount() {
return answersSize;
}
};
spinDetail.setAdapter(detailAdapter);
spinDetail.setSelection(answersSize);
params.setMargins(marginStart, marginTop, marginEnd, 0);
spinDetail.setLayoutParams(params);
params.setMargins(0, marginTop, marginEnd, 0);
txtDetail.setLayoutParams(params);
detailSpinners[i] = spinDetail;
}
}
I can't put a wrap_content height for the spinners because if I do they aren't visible.
I don't think that the xml is the problem because I used a lot of spinners with the same code and I never had this issue. The difference is that I edit the LayoutParams programmatically and there's probably something I'm doing wrong.
I just want the spinners to keep the same height.

Set the padding to 0 on the spinner xml element.
<Spinner
android:id="#+id/spinDetail1"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:padding="0dp"
android:background="#drawable/spinner"/>
Update:
The wrapping LinearLayout has a height of "wrap_content" while the Spinner has a height of "match_parent", assuming this will act the same as wrap_content as it is only constrained by the LinearLayout.
Setting a specified height in pixels to the Spinner should resolve this.
android:layout_height="60dp"

Full width Navigation Drawer

I'd like to create a full width navigation drawer. Setting layout_width to match_parent on #+id/left_drawer yields in width of about 80% of screen space. This seems to be the standard behavior. Do I have to override onMeasure() of DrawerLayout?
My current code:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black"
android:id="#+id/mainFragmentContainer">
</FrameLayout>
<include
android:id="#+id/left_drawer"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start"
layout="#layout/drawer"/>
</android.support.v4.widget.DrawerLayout>
Thanks.

If you want simpler solution you can just set negative margin
android:layout_marginLeft="-64dp"
for your left_drawer:
<include
android:id="#+id/left_drawer"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start"
layout="#layout/drawer"
android:layout_marginLeft="-64dp"/>

Because all these answers did not work on OS 6.0.1, I'll post here the solution that worked for me in combination with DrawerLayout + NavigationView.
So all what I do is change the width of the NavigationView programatically:
mNavigationView = (NavigationView) findViewById(R.id.nv_navigation);
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
DrawerLayout.LayoutParams params = (DrawerLayout.LayoutParams) mNavigationView.getLayoutParams();
params.width = metrics.widthPixels;
mNavigationView.setLayoutParams(params);
This works for all screen sizes.

Yes, you have to extend DrawerLayout and override some methods because MIN_DRAWER_MARGIN is private
Here is a possible solution:
public class FullDrawerLayout extends DrawerLayout {
private static final int MIN_DRAWER_MARGIN = 0; // dp
public FullDrawerLayout(Context context) {
super(context);
}
public FullDrawerLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public FullDrawerLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
final int heightSize = MeasureSpec.getSize(heightMeasureSpec);
if (widthMode != MeasureSpec.EXACTLY || heightMode != MeasureSpec.EXACTLY) {
throw new IllegalArgumentException(
"DrawerLayout must be measured with MeasureSpec.EXACTLY.");
}
setMeasuredDimension(widthSize, heightSize);
// Gravity value for each drawer we've seen. Only one of each permitted.
int foundDrawers = 0;
final int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
if (isContentView(child)) {
// Content views get measured at exactly the layout's size.
final int contentWidthSpec = MeasureSpec.makeMeasureSpec(
widthSize - lp.leftMargin - lp.rightMargin, MeasureSpec.EXACTLY);
final int contentHeightSpec = MeasureSpec.makeMeasureSpec(
heightSize - lp.topMargin - lp.bottomMargin, MeasureSpec.EXACTLY);
child.measure(contentWidthSpec, contentHeightSpec);
} else if (isDrawerView(child)) {
final int childGravity =
getDrawerViewGravity(child) & Gravity.HORIZONTAL_GRAVITY_MASK;
if ((foundDrawers & childGravity) != 0) {
throw new IllegalStateException("Child drawer has absolute gravity " +
gravityToString(childGravity) + " but this already has a " +
"drawer view along that edge");
}
final int drawerWidthSpec = getChildMeasureSpec(widthMeasureSpec,
MIN_DRAWER_MARGIN + lp.leftMargin + lp.rightMargin,
lp.width);
final int drawerHeightSpec = getChildMeasureSpec(heightMeasureSpec,
lp.topMargin + lp.bottomMargin,
lp.height);
child.measure(drawerWidthSpec, drawerHeightSpec);
} else {
throw new IllegalStateException("Child " + child + " at index " + i +
" does not have a valid layout_gravity - must be Gravity.LEFT, " +
"Gravity.RIGHT or Gravity.NO_GRAVITY");
}
}
}
boolean isContentView(View child) {
return ((LayoutParams) child.getLayoutParams()).gravity == Gravity.NO_GRAVITY;
}
boolean isDrawerView(View child) {
final int gravity = ((LayoutParams) child.getLayoutParams()).gravity;
final int absGravity = Gravity.getAbsoluteGravity(gravity,
child.getLayoutDirection());
return (absGravity & (Gravity.LEFT | Gravity.RIGHT)) != 0;
}
int getDrawerViewGravity(View drawerView) {
final int gravity = ((LayoutParams) drawerView.getLayoutParams()).gravity;
return Gravity.getAbsoluteGravity(gravity, drawerView.getLayoutDirection());
}
static String gravityToString(int gravity) {
if ((gravity & Gravity.LEFT) == Gravity.LEFT) {
return "LEFT";
}
if ((gravity & Gravity.RIGHT) == Gravity.RIGHT) {
return "RIGHT";
}
return Integer.toHexString(gravity);
}
}

Based on the Robert's Answer, you can use the layout_marginLeft=-64dp to solve this problem easily.
However it doesn't seems to work anymore on Android 5.0 and above. So here's my solution that worked for me.
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
android:id="#+id/drawer_layout"
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:layout_marginRight="-64dp"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
layout="#layout/content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginRight="64dp"/>
<include
android:id="#+id/left_drawer"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start"
layout="#layout/drawer"/>
</android.support.v4.widget.DrawerLayout>
Basically, Add android:layout_marginRight="-64dp" to the root DrawerLayout so all the layout will go to the right for 64dp.
Then I add the layout_marginRight=64dp to the content so it goes back to the original position. Then you can have a full drawer there.

A variant on Grogory's solution:
Instead of subclassing I call the following utility method right after I grab a reference to the drawer layout:
/**
* The specs tell that
* <ol>
* <li>Navigation Drawer should be at most 5*56dp wide on phones and 5*64dp wide on tablets.</li>
* <li>Navigation Drawer should have right margin of 56dp on phones and 64dp on tablets.</li>
* </ol>
* yet the minimum margin is hardcoded to be 64dp instead of 56dp. This fixes it.
*/
public static void fixMinDrawerMargin(DrawerLayout drawerLayout) {
try {
Field f = DrawerLayout.class.getDeclaredField("mMinDrawerMargin");
f.setAccessible(true);
f.set(drawerLayout, 0);
drawerLayout.requestLayout();
} catch (Exception e) {
e.printStackTrace();
}
}

Nipper's FullDrawerLayout Class is just simply awesome.. it's performance is also faster than the default drawer how ever you can;t use it on devices with api that don't have view.getLayoutDirection();
(i'e : Class doesn;t work on all gingerbread devices )
so what i did was
replaced all
view.getLayoutDirection();
with the below code
GravityCompat.getAbsoluteGravity(gravity,ViewCompat.getLayoutDirection(this));
I have my support library updated to the latest also have extended the fullDrawerlayout to the support navigational drawer. Now it works fine Gingerbread devices as well

Another possible way to solve the issue without overriding too much:
public class FullScreenDrawerLayout extends DrawerLayout {
... //List of constructors calling
... //super(...);
... //init();
/** Make DrawerLayout to take the whole screen. */
protected void init() {
try {
Field field = getClass().getSuperclass().getDeclaredField("mMinDrawerMargin");
field.setAccessible(true);
field.set(this, Integer.valueOf(0));
} catch (Exception e) {
throw new IllegalStateException("android.support.v4.widget.DrawerLayout has changed and you have to fix this class.", e);
}
}
}
If, at some point, support library is updated and mMinDrawerMargin is not there anymore you will get exception and fix problem before you publish your next update.
I didn't make measurements, but suppose there is not so many reflection to affect performance. Furthermore, it executes only per view creation.
PS
it's strange why DrawerLayout is made so inflexible (I'm about private min margin) at this point...

Try out this worked for me :
<include
android:id="#+id/left_drawer"
android:orientation="vertical"
android:layout_width="320dp"
android:layout_height="match_parent"
android:layout_gravity="start"
layout="#layout/drawer"/>
Set width of included layout android:layout_width="320dp". For devices with different screen size you can dynamically set the width of this included layout.

You can use this. Inspired by this post, I've upgraded for the 5th edition. Because it was having problems with StatusBar in versions 5 and later.
you have to extend DrawerLayout and override some methods because MIN_DRAWER_MARGIN is private
public class FullDrawerLayout extends DrawerLayout {
private static final int MIN_DRAWER_MARGIN = 0; // dp
public FullDrawerLayout(Context context) {
super(context);
}
public FullDrawerLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public FullDrawerLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
final int heightSize = MeasureSpec.getSize(heightMeasureSpec);
if (widthMode != MeasureSpec.EXACTLY || heightMode != MeasureSpec.EXACTLY) {
throw new IllegalArgumentException(
"DrawerLayout must be measured with MeasureSpec.EXACTLY.");
}
setMeasuredDimension(widthSize, heightSize);
//for support Android 5+
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP) {
FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) getLayoutParams();
params.topMargin = getStatusBarHeight();
setLayoutParams(params);
}
// Gravity value for each drawer we've seen. Only one of each permitted.
int foundDrawers = 0;
final int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
if (isContentView(child)) {
// Content views get measured at exactly the layout's size.
final int contentWidthSpec = MeasureSpec.makeMeasureSpec(
widthSize - lp.leftMargin - lp.rightMargin, MeasureSpec.EXACTLY);
final int contentHeightSpec = MeasureSpec.makeMeasureSpec(
heightSize - lp.topMargin - lp.bottomMargin, MeasureSpec.EXACTLY);
child.measure(contentWidthSpec, contentHeightSpec);
} else if (isDrawerView(child)) {
final int childGravity =
getDrawerViewGravity(child) & Gravity.HORIZONTAL_GRAVITY_MASK;
if ((foundDrawers & childGravity) != 0) {
throw new IllegalStateException("Child drawer has absolute gravity " +
gravityToString(childGravity) + " but this already has a " +
"drawer view along that edge");
}
final int drawerWidthSpec = getChildMeasureSpec(widthMeasureSpec,
MIN_DRAWER_MARGIN + lp.leftMargin + lp.rightMargin,
lp.width);
final int drawerHeightSpec = getChildMeasureSpec(heightMeasureSpec,
lp.topMargin + lp.bottomMargin,
lp.height);
child.measure(drawerWidthSpec, drawerHeightSpec);
} else {
throw new IllegalStateException("Child " + child + " at index " + i +
" does not have a valid layout_gravity - must be Gravity.LEFT, " +
"Gravity.RIGHT or Gravity.NO_GRAVITY");
}
}
}
boolean isContentView(View child) {
return ((LayoutParams) child.getLayoutParams()).gravity == Gravity.NO_GRAVITY;
}
boolean isDrawerView(View child) {
final int gravity = ((LayoutParams) child.getLayoutParams()).gravity;
final int absGravity = Gravity.getAbsoluteGravity(gravity,
child.getLayoutDirection());
return (absGravity & (Gravity.LEFT | Gravity.RIGHT)) != 0;
}
int getDrawerViewGravity(View drawerView) {
final int gravity = ((LayoutParams) drawerView.getLayoutParams()).gravity;
return Gravity.getAbsoluteGravity(gravity, drawerView.getLayoutDirection());
}
static String gravityToString(int gravity) {
if ((gravity & Gravity.LEFT) == Gravity.LEFT) {
return "LEFT";
}
if ((gravity & Gravity.RIGHT) == Gravity.RIGHT) {
return "RIGHT";
}
return Integer.toHexString(gravity);
}
public int getStatusBarHeight() {
int result = 0;
int resourceId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resourceId > 0) {
result = getResources().getDimensionPixelSize(resourceId);
}
return result;
}
}

you can by below code
int width = getResources().getDisplayMetrics().widthPixels/2;
DrawerLayout.LayoutParams params = (android.support.v4.widget.DrawerLayout.LayoutParams) drawer_Linear_layout.getLayoutParams();
params.width = width;
drawer_Linear_layout.setLayoutParams(params);

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout 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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<FrameLayout
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<include
layout="#layout/app_bar_dashboard"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</FrameLayout>
<android.support.design.widget.NavigationView
android:id="#+id/nav_view"
android:layout_width="match_parent"
android:layout_marginRight="32dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true">
<include layout="#layout/view_navigation_menu" />
</android.support.design.widget.NavigationView>
</android.support.v4.widget.DrawerLayout>
That's works perfectly for me. Hope help others.

Google recommends having a maxim width of 320 dip as per the UI guidelines here.
Moreover, the width can be set by specified the layout_width of the left_drawer ListView.

<?xml version="1.0" encoding="utf-8"?><LinearLayout 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:orientation="vertical"
tools:context=".UserListActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:background="#drawable/common_gradient"
android:layoutDirection="rtl"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="0.2">
<TextView
android:id="#+id/userType_textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="نوع المستخدم"
android:textColor="#000000"
android:textSize="20sp"
tools:text="نوع المستخدم" />
<TextView
android:id="#+id/className_textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/userType_textView"
android:layout_centerHorizontal="true"
android:text="إسم القسم"
android:textColor="#000000"
android:textSize="16sp"
tools:text="إسم القسم" />
<ImageButton
android:layout_width="30dp"
android:layout_height="20dp"
android:layout_alignBottom="#+id/userType_textView"
android:layout_marginLeft="15dp"
android:layout_marginStart="15dp"
android:background="#android:color/transparent"
android:contentDescription="#string/desc"
android:onClick="showMenuAction"
android:scaleType="fitCenter"
android:src="#drawable/menu" />
</RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="0.8"
android:background="#FAFAFA">
<SearchView
android:id="#+id/user_searchView"
android:layout_width="match_parent"
android:layout_height="45dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:background="#9CC3D7" />
<ListView
android:id="#+id/users_listView"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_alignParentBottom="true"
android:layout_below="#+id/user_searchView"
android:layout_centerHorizontal="true"
android:divider="#DFDEE1"
android:dividerHeight="1dp" />
</RelativeLayout>
</LinearLayout>
<android.support.v4.widget.DrawerLayout
android:id="#+id/navigationDrawerUser"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layoutDirection="rtl">
<ExpandableListView
android:id="#+id/menu_listView_user"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#195269"
android:choiceMode="singleChoice"
android:divider="#2C637D"
android:dividerHeight="1dp"
android:groupIndicator="#null">
</ExpandableListView>
</android.support.v4.widget.DrawerLayout>

Everyone thinks that full-width Sidebar Drawer layout creation is very complicated, but it's very simple if you are following this layout pattern, you don't need to set any minus value.
This is my MainActivity.xml:
<androidx.drawerlayout.widget.DrawerLayout
android:id="#+id/drawerLayout"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Main Activity -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include
android:id="#+id/toolbarMain"
android:layout_width="match_parent"
android:layout_height="wrap_content"
layout="#layout/layout_profile_toolbar"/>
<androidx.fragment.app.FragmentContainerView
android:id="#+id/fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="#navigation/app_navigation" />
</LinearLayout>
<!-- Main Activity End -->
<!-- Custom Navigation Drawer Start -->
<com.google.android.material.navigation.NavigationView
android:id="#+id/nav_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true">
<include
android:id="#+id/custom_nav"
android:layout_width="match_parent"
android:layout_height="match_parent"
layout="#layout/fragment_profile"/>
</com.google.android.material.navigation.NavigationView>
<!-- Custom Navigation Drawer End -->
</androidx.drawerlayout.widget.DrawerLayout>

You can set width programmatically.
Give screen full width to navigation view's width.
NavigationView navigationView = findViewById(R.id.nav_view);
DrawerLayout.LayoutParams params = (DrawerLayout.LayoutParams) navigationView.getLayoutParams();
params.width = Utils.screenWidth(this);

You can also take a look at SlidingDrawer class. It's a deprecated class, but as the documentation says you can write your own implementation based on its source code.

How to find layout_marginTop

I have an XML file with the following attritubes:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/al_cs_layout1"
android:gravity="center_vertical">
<ImageView android:id="#+id/cs_track"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/fader_background5"
android:layout_marginLeft="0dp"
android:layout_marginTop="20dp" >
</ImageView>
...
and here is my java code:
public void initialize(Context context)
{
Log.d("initialize (MySeekBar)","initialize");
setWillNotDraw(false);
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view1 = inflater.inflate(R.layout.custom_seekbar, this);
layout1 = (RelativeLayout)view1.findViewById(R.id.al_cs_layout1);
track = (ImageView)layout1.findViewById(R.id.cs_track);
thumb = (ImageView)layout1.findViewById(R.id.cs_thumb);
...
I am working on a custom seekbar which determines the top by using a variable marginTop = 20; however this was oringally made on a phone much older by a different programmer. The 20 suppose to represent the margin top defined in the XML however it is using dp and not pixels. how can I find the marginTop attribute of R.id.cs_track? It works great on the old phone but on any phone does doesn't have the same screen size of dp it will create an undesired offset.

Use MarginLayoutParams to get value in pixels:
track = (ImageView)layout1.findViewById(R.id.cs_track);
MarginLayoutParams params = (MarginLayoutParams)track.getLayoutParams();
int marginTopPixelSize = params.topMargin;

Aligning drawableLeft with text of button

Here is my layout:
The issue I'm facing is with the drawable checkmark. How would I go about aligning it next to the text, both of them centered within the button? Here is the XML:
<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"
tools:context=".PostAssignmentActivity" >
<LinearLayout
style="?android:attr/buttonBarStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:orientation="horizontal" >
<Button
style="?android:attr/buttonBarButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:drawableLeft="#drawable/ic_checkmark_holo_light"
android:text="Post" />
<Button
style="?android:attr/buttonBarButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Cancel" />
</LinearLayout>
</RelativeLayout>
Applying android:gravity="center_vertical" pulls the text and drawable together, but then the text is no longer aligned in the center.

Solution 1
Set android:paddingLeft inside your first button. This will force the drawableLeft by paddingLeft amount to the right. This is the fast/hacky solution.
Solution 2
Instead of using a ButtonView, use a LinearLayout that contains both a textview and imageview. This is a better solution. It gives you more flexibility in the positioning of the checkmark.
Replace your ButtonView with the following code. You need the LinearLayout and TextView to use buttonBarButtonStyle so that the background colors are correct on selection and the text size is correct. You need to set android:background="#0000" for the children, so that only the LinearLayout handles the background coloring.
<LinearLayout
style="?android:attr/buttonBarButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal" >
<ImageView
style="?android:attr/buttonBarButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="false"
android:background="#0000"
android:src="#drawable/ic_checkmark_holo_light"/>
<TextView
style="?android:attr/buttonBarButtonStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="false"
android:background="#0000"
android:text="Done" />
</LinearLayout>
Here are some screenshots I took while trying this out.

None of these solutions worked correctly without presenting unacceptable trade-offs (create a layout with views in it? Not a good idea). So why not roll your own? This is what I got:
First create an attrs.xml with this:
<resources>
<declare-styleable name="IconButton">
<attr name="iconSrc" format="reference" />
<attr name="iconSize" format="dimension" />
<attr name="iconPadding" format="dimension" />
</declare-styleable>
</resources>
This allows to create an icon with specific size, padding from text, and image in our new view. The view code looks like this:
public class IconButton extends Button {
private Bitmap mIcon;
private Paint mPaint;
private Rect mSrcRect;
private int mIconPadding;
private int mIconSize;
public IconButton(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs);
}
public IconButton(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public IconButton(Context context) {
super(context);
}
#Override
protected void onDraw(Canvas canvas) {
int shift = (mIconSize + mIconPadding) / 2;
canvas.save();
canvas.translate(shift, 0);
super.onDraw(canvas);
if (mIcon != null) {
float textWidth = getPaint().measureText((String)getText());
int left = (int)((getWidth() / 2f) - (textWidth / 2f) - mIconSize - mIconPadding);
int top = getHeight()/2 - mIconSize/2;
Rect destRect = new Rect(left, top, left + mIconSize, top + mIconSize);
canvas.drawBitmap(mIcon, mSrcRect, destRect, mPaint);
}
canvas.restore();
}
private void init(Context context, AttributeSet attrs) {
TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.IconButton);
for (int i = 0; i < array.getIndexCount(); ++i) {
int attr = array.getIndex(i);
switch (attr) {
case R.styleable.IconButton_iconSrc:
mIcon = drawableToBitmap(array.getDrawable(attr));
break;
case R.styleable.IconButton_iconPadding:
mIconPadding = array.getDimensionPixelSize(attr, 0);
break;
case R.styleable.IconButton_iconSize:
mIconSize = array.getDimensionPixelSize(attr, 0);
break;
default:
break;
}
}
array.recycle();
//If we didn't supply an icon in the XML
if(mIcon != null){
mPaint = new Paint();
mSrcRect = new Rect(0, 0, mIcon.getWidth(), mIcon.getHeight());
}
}
public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}
Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
}
And then it can be used like this:
<com.example.grennis.myapplication.IconButton
android:layout_width="200dp"
android:layout_height="64dp"
android:text="Delete"
app:iconSrc="#android:drawable/ic_delete"
app:iconSize="32dp"
app:iconPadding="6dp" />
This works for me.

You can use
<com.google.android.material.button.MaterialButton/> .
https://material.io/develop/android/components/material-button/
It finally allows setting the icon gravity.
<com.google.android.material.button.MaterialButton
android:layout_width="match_parent"
android:layout_height="48dp"
android:layout_marginStart="16dp"
android:layout_marginEnd="16dp"
android:gravity="center"
android:text="Awesome button"
app:icon="#drawable/your_icon"
app:iconGravity="textStart" />

Here is a clean easy way, without doing anything fancy, to achieve the results of having a Button that is much wider than the content with Image and Text which are centered.
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:background="#drawable/button_background_selector">
<Button
android:layout_centerInParent="true"
android:gravity="center"
android:duplicateParentState="true"
android:layout_width="wrap_content"
android:text="New User"
android:textSize="15sp"
android:id="#android:id/button1"
android:textColor="#android:color/white"
android:drawablePadding="6dp"
android:drawableLeft="#drawable/add_round_border_32x32"
android:layout_height="64dp" />
</RelativeLayout>

In our case, we wanted to use the default Button class (to inherit its various styles and behaviors) and we needed to be able to create the button in code. Also, in our case we could have text, an icon (left drawable), or both.
The goal was to center the icon and/or text as a group when the button width was wider than wrap_content.
public class CenteredButton extends Button
{
public CenteredButton(Context context, AttributeSet attrs, int defStyleAttr)
{
super(context, attrs, defStyleAttr);
// We always want our icon and/or text grouped and centered. We have to left align the text to
// the (possible) left drawable in order to then be able to center them in our onDraw() below.
//
setGravity(Gravity.LEFT|Gravity.CENTER_VERTICAL);
}
#Override
protected void onDraw(Canvas canvas)
{
// We want the icon and/or text grouped together and centered as a group.
// We need to accommodate any existing padding
//
float buttonContentWidth = getWidth() - getPaddingLeft() - getPaddingRight();
// In later versions of Android, an "all caps" transform is applied to buttons. We need to get
// the transformed text in order to measure it.
//
TransformationMethod method = getTransformationMethod();
String buttonText = ((method != null) ? method.getTransformation(getText(), this) : getText()).toString();
float textWidth = getPaint().measureText(buttonText);
// Compute left drawable width, if any
//
Drawable[] drawables = getCompoundDrawables();
Drawable drawableLeft = drawables[0];
int drawableWidth = (drawableLeft != null) ? drawableLeft.getIntrinsicWidth() : 0;
// We only count the drawable padding if there is both an icon and text
//
int drawablePadding = ((textWidth > 0) && (drawableLeft != null)) ? getCompoundDrawablePadding() : 0;
// Adjust contents to center
//
float bodyWidth = textWidth + drawableWidth + drawablePadding;
canvas.translate((buttonContentWidth - bodyWidth) / 2, 0);
super.onDraw(canvas);
}
}

Here is my code and working perfect.
<Button
android:id="#+id/button"
android:layout_width="200dp"
android:layout_height="50dp"
android:layout_gravity="center"
android:background="#drawable/green_btn_selector"
android:gravity="left|center_vertical"
android:paddingLeft="50dp"
android:drawableLeft="#drawable/plus"
android:drawablePadding="5dp"
android:text="#string/create_iou"
android:textColor="#color/white" />

public class DrawableCenterTextView extends TextView {
public DrawableCenterTextView(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
}
public DrawableCenterTextView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public DrawableCenterTextView(Context context) {
super(context);
}
#Override
protected void onDraw(Canvas canvas) {
Drawable[] drawables = getCompoundDrawables();
if (drawables != null) {
Drawable drawableLeft = drawables[0];
Drawable drawableRight = drawables[2];
if (drawableLeft != null || drawableRight != null) {
float textWidth = getPaint().measureText(getText().toString());
int drawablePadding = getCompoundDrawablePadding();
int drawableWidth = 0;
if (drawableLeft != null)
drawableWidth = drawableLeft.getIntrinsicWidth();
else if (drawableRight != null) {
drawableWidth = drawableRight.getIntrinsicWidth();
}
float bodyWidth = textWidth + drawableWidth + drawablePadding;
canvas.translate((getWidth() - bodyWidth) / 2, 0);
}
}
super.onDraw(canvas);
}
}

This is now available in the Material Button by default with the app:iconGravity property. However, the Material Button does not allow for setting the background to a drawable (RIP gradients).
I converted the answers by #BobDickinson and #David-Medenjak above to kotlin and it works great.
import android.content.Context
import android.graphics.Canvas
import android.util.AttributeSet
import android.view.Gravity
import androidx.appcompat.widget.AppCompatButton
import kotlin.math.max
class CenteredButton #JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyle: Int = R.attr.buttonStyle
) : AppCompatButton(context, attrs, defStyle) {
init {
gravity = Gravity.LEFT or Gravity.CENTER_VERTICAL
}
override fun onDraw(canvas: Canvas) {
val buttonContentWidth = (width - paddingLeft - paddingRight).toFloat()
var textWidth = 0f
layout?.let {
for (i in 0 until layout.lineCount) {
textWidth = max(textWidth, layout.getLineRight(i))
}
}
val drawableLeft = compoundDrawables[0]
val drawableWidth = drawableLeft?.intrinsicWidth ?: 0
val drawablePadding = if (textWidth > 0 && drawableLeft != null) compoundDrawablePadding else 0
val bodyWidth = textWidth + drawableWidth.toFloat() + drawablePadding.toFloat()
canvas.save()
canvas.translate((buttonContentWidth - bodyWidth) / 2, 0f)
super.onDraw(canvas)
canvas.restore()
}
}

I know it's a bit late, but if anyone looking for another answer, here is another way to add icon without the need to wrap button with a ViewGroup
<?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/btnCamera"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Click!"
android:textAllCaps="false"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
*need to set textAllCaps to false to make the spannable working
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val buttonLabelBuilder = SpannableStringBuilder(btnCamera.text)
val iconDrawable = AppCompatResources.getDrawable(this, R.drawable.ic_camera)
iconDrawable?.setBounds(0, 0, btnCamera.lineHeight, btnCamera.lineHeight)
val imageSpan = ImageSpan(iconDrawable, ImageSpan.ALIGN_BOTTOM)
buttonLabelBuilder.insert(0, "i ")
buttonLabelBuilder.setSpan(imageSpan, 0, 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)
btnCamera.text = buttonLabelBuilder
}
}

I started with #BobDickinson's answer, but it did not cope well with multiple lines. The approach is good, because you still end up with a Button that can properly be reused.
Here is an adapted solution that will also work if the button has multiple lines (Please don't ask why.)
Just extend Button and use the following in onDraw, the getLineRight() is used to look up the actual length of each line.
#Override
protected void onDraw(Canvas canvas) {
// We want the icon and/or text grouped together and centered as a group.
// We need to accommodate any existing padding
final float buttonContentWidth = getWidth() - getPaddingLeft() - getPaddingRight();
float textWidth = 0f;
final Layout layout = getLayout();
if (layout != null) {
for (int i = 0; i < layout.getLineCount(); i++) {
textWidth = Math.max(textWidth, layout.getLineRight(i));
}
}
// Compute left drawable width, if any
Drawable[] drawables = getCompoundDrawables();
Drawable drawableLeft = drawables[0];
int drawableWidth = (drawableLeft != null) ? drawableLeft.getIntrinsicWidth() : 0;
// We only count the drawable padding if there is both an icon and text
int drawablePadding = ((textWidth > 0) && (drawableLeft != null)) ? getCompoundDrawablePadding() : 0;
// Adjust contents to center
float bodyWidth = textWidth + drawableWidth + drawablePadding;
canvas.save();
canvas.translate((buttonContentWidth - bodyWidth) / 2, 0);
super.onDraw(canvas);
canvas.restore();
}

Here is a another solution:
<LinearLayout
android:id="#+id/llButton"
android:layout_width="match_parent"
style="#style/button_celeste"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
style="#style/button_celeste"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawablePadding="10dp"
android:clickable="false"
android:drawableLeft="#drawable/icon_phone"
android:text="#string/call_runid"/>
</LinearLayout>
and the event:
LinearLayout btnCall = (LinearLayout) findViewById(R.id.llButton);
btnCall.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
call(runid.Phone);
}
});

I had the same issue, and I've come up with a solution that doesn't require XML changes or custom Views.
This code snippet retrieves the width of the text and the left/right drawables, and sets the Button's left/right padding so there will only be enough space to draw the text and the drawables, and no more padding will be added.
This can be applied to Buttons as well as TextViews, their superclasses.
public class TextViewUtils {
private static final int[] LEFT_RIGHT_DRAWABLES = new int[]{0, 2};
public static void setPaddingForCompoundDrawableNextToText(final TextView textView) {
ViewTreeObserver vto = textView.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
shinkRoomForHorizontalSpace(textView);
}
});
}
private static void shinkRoomForHorizontalSpace(TextView textView) {
int textWidth = getTextWidth(textView);
int sideCompoundDrawablesWidth = getSideCompoundDrawablesWidth(textView);
int contentWidth = textWidth + sideCompoundDrawablesWidth;
int innerWidth = getInnerWidth(textView);
int totalPadding = innerWidth - contentWidth;
textView.setPadding(totalPadding / 2, 0, totalPadding / 2, 0);
}
private static int getTextWidth(TextView textView) {
String text = textView.getText().toString();
Paint textPaint = textView.getPaint();
Rect bounds = new Rect();
textPaint.getTextBounds(text, 0, text.length(), bounds);
return bounds.width();
}
private static int getSideCompoundDrawablesWidth(TextView textView) {
int sideCompoundDrawablesWidth = 0;
Drawable[] drawables = textView.getCompoundDrawables();
for (int drawableIndex : LEFT_RIGHT_DRAWABLES) {
Drawable drawable = drawables[drawableIndex];
if (drawable == null)
continue;
int width = drawable.getBounds().width();
sideCompoundDrawablesWidth += width;
}
return sideCompoundDrawablesWidth;
}
private static int getInnerWidth(TextView textView) {
Rect backgroundPadding = new Rect();
textView.getBackground().getPadding(backgroundPadding);
return textView.getWidth() - backgroundPadding.left - backgroundPadding.right;
}
}
Notice that:
It actually still leaves some more space than needed (good enough for my purposes, but you may look for the error)
It overwrites whatever left/right padding is there. I guess it's not difficult to fix that.
To use it, just call TextViewUtils.setPaddingForCompoundDrawableNextToText(button) on your onCreate or onViewCreated().

There are several solutions to this problem. Perhaps the easiest on some devices is to use paddingRight and paddingLeft to move the image and text next to each other as below.
Original button
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginEnd="32dp"
android:layout_marginTop="16dp"
android:text="#string/scan_qr_code"
android:textColor="#color/colorPrimary"
android:drawableLeft="#drawable/ic_camera"
android:paddingRight="90dp"
android:paddingLeft="90dp"
android:gravity="center"
/>
The problem here is on smaller devices this padding can cause unfortunate problems such as this:
The other solutions are all some version of "build a button out of a layout an image and a textview". They work, but completely emulating a button can be tricky. I propose one more solution; "build a button out of a layout an image, a textview, and a button"
Here's the same button rendered as I propose:
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginEnd="32dp"
android:layout_marginTop="16dp"
android:gravity="center"
>
<Button
android:id="#+id/scanQR"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/white_bg_button"
/>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_centerInParent="true"
android:gravity="center"
android:elevation="10dp"
>
<ImageView
android:id="#+id/scanImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="8dp"
android:src="#drawable/ic_camera"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="#style/Base.TextAppearance.AppCompat.Button"
android:text="#string/scan_qr_code"
android:textColor="#color/colorPrimary"
/>
</LinearLayout>
</RelativeLayout>
As you can see, the button is now within a relative layout, but it's text and drawableLeft are not part of the button, they are in a separate layout that's placed on top of the button. With this, the button still acts like a button. The gotchas are:
The inner layout needs an elevation for newer versions of Android. The button itself has an elevation greater than the ImageView and TextView, so even though they are defined after the Button, they will still be "below" it in elevation and be invisible. Setting 'android:elevation' to 10 solves this.
The textAppearance of the TextView must be set so that it has the same appearance as it would in a button.

Another quite hacky alternative is to add blank spacer views with weight="1" on each side of the buttons. I don't know how this would affect performance.
<View
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1" />

Fixed aspect ratio View

How would I go implementing a fixed aspect ratio View? I'd like to have items with 1:1 aspect ratio in a GridView. I think it's better to subclass the children than the GridView?
EDIT: I assume this needs to be done programmatically, that's no problem. Also, I don't want to limit the size, only the aspect ratio.

I implemented FixedAspectRatioFrameLayout, so I can reuse it and have any hosted view be with fixed aspect ratio:
public class FixedAspectRatioFrameLayout extends FrameLayout
{
private int mAspectRatioWidth;
private int mAspectRatioHeight;
public FixedAspectRatioFrameLayout(Context context)
{
super(context);
}
public FixedAspectRatioFrameLayout(Context context, AttributeSet attrs)
{
super(context, attrs);
init(context, attrs);
}
public FixedAspectRatioFrameLayout(Context context, AttributeSet attrs, int defStyle)
{
super(context, attrs, defStyle);
init(context, attrs);
}
private void init(Context context, AttributeSet attrs)
{
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.FixedAspectRatioFrameLayout);
mAspectRatioWidth = a.getInt(R.styleable.FixedAspectRatioFrameLayout_aspectRatioWidth, 4);
mAspectRatioHeight = a.getInt(R.styleable.FixedAspectRatioFrameLayout_aspectRatioHeight, 3);
a.recycle();
}
// **overrides**
#Override protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec)
{
int originalWidth = MeasureSpec.getSize(widthMeasureSpec);
int originalHeight = MeasureSpec.getSize(heightMeasureSpec);
int calculatedHeight = originalWidth * mAspectRatioHeight / mAspectRatioWidth;
int finalWidth, finalHeight;
if (calculatedHeight > originalHeight)
{
finalWidth = originalHeight * mAspectRatioWidth / mAspectRatioHeight;
finalHeight = originalHeight;
}
else
{
finalWidth = originalWidth;
finalHeight = calculatedHeight;
}
super.onMeasure(
MeasureSpec.makeMeasureSpec(finalWidth, MeasureSpec.EXACTLY),
MeasureSpec.makeMeasureSpec(finalHeight, MeasureSpec.EXACTLY));
}
}

For new users, here's a better non-code solution :
A new support library called Percent Support Library is available in Android SDK v22 (MinAPI is 7 me thinks, not sure) :
src : android-developers.blogspot.in
The Percent Support Library provides percentage based dimensions and margins and, new to this release, the ability to set a custom aspect ratio via app:aspectRatio. By setting only a single width or height and using aspectRatio, the PercentFrameLayout or PercentRelativeLayout will automatically adjust the other dimension so that the layout uses a set aspect ratio.
To include add this to your build.gradle :
compile 'com.android.support:percent:23.1.1'
Now wrap your view (the one that needs to be square) with a PercentRelativeLayout / PercentFrameLayout :
<android.support.percent.PercentRelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
app:layout_aspectRatio="100%"
app:layout_widthPercent="100%"/>
</android.support.percent.PercentRelativeLayout>
You can see an example here.

To not use third-party solution and considering the fact that both PercentFrameLayout and PercentRelativeLayout were deprecated in 26.0.0, I'd suggest you to consider using ConstraintLayout as a root layout for your grid items.
Your item_grid.xml might look like:
<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="wrap_content">
<ImageView
android:id="#+id/imageview_item"
android:layout_width="0dp"
android:layout_height="0dp"
android:scaleType="centerCrop"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintDimensionRatio="H,1:1" />
</android.support.constraint.ConstraintLayout>
As a result you get something like this:

I recently made a helper class for this very problem and wrote a blog post about it.
The meat of the code is as follows:
/**
* Measure with a specific aspect ratio<br />
* <br />
* #param widthMeasureSpec The width <tt>MeasureSpec</tt> passed in your <tt>View.onMeasure()</tt> method
* #param heightMeasureSpec The height <tt>MeasureSpec</tt> passed in your <tt>View.onMeasure()</tt> method
* #param aspectRatio The aspect ratio to calculate measurements in respect to
*/
public void measure(int widthMeasureSpec, int heightMeasureSpec, double aspectRatio) {
int widthMode = MeasureSpec.getMode( widthMeasureSpec );
int widthSize = widthMode == MeasureSpec.UNSPECIFIED ? Integer.MAX_VALUE : MeasureSpec.getSize( widthMeasureSpec );
int heightMode = MeasureSpec.getMode( heightMeasureSpec );
int heightSize = heightMode == MeasureSpec.UNSPECIFIED ? Integer.MAX_VALUE : MeasureSpec.getSize( heightMeasureSpec );
if ( heightMode == MeasureSpec.EXACTLY && widthMode == MeasureSpec.EXACTLY ) {
/*
* Possibility 1: Both width and height fixed
*/
measuredWidth = widthSize;
measuredHeight = heightSize;
} else if ( heightMode == MeasureSpec.EXACTLY ) {
/*
* Possibility 2: Width dynamic, height fixed
*/
measuredWidth = (int) Math.min( widthSize, heightSize * aspectRatio );
measuredHeight = (int) (measuredWidth / aspectRatio);
} else if ( widthMode == MeasureSpec.EXACTLY ) {
/*
* Possibility 3: Width fixed, height dynamic
*/
measuredHeight = (int) Math.min( heightSize, widthSize / aspectRatio );
measuredWidth = (int) (measuredHeight * aspectRatio);
} else {
/*
* Possibility 4: Both width and height dynamic
*/
if ( widthSize > heightSize * aspectRatio ) {
measuredHeight = heightSize;
measuredWidth = (int)( measuredHeight * aspectRatio );
} else {
measuredWidth = widthSize;
measuredHeight = (int) (measuredWidth / aspectRatio);
}
}
}

I created a layout library using TalL's answer. Feel free to use it.
RatioLayouts
Installation
Add this to the top of the file
repositories {
maven {
url "http://dl.bintray.com/riteshakya037/maven"
}
}
dependencies {
compile 'com.ritesh:ratiolayout:1.0.0'
}
Usage
Define 'app' namespace on root view in your layout
xmlns:app="http://schemas.android.com/apk/res-auto"
Include this library in your layout
<com.ritesh.ratiolayout.RatioRelativeLayout
android:id="#+id/activity_main_ratio_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:fixed_attribute="WIDTH" // Fix one side of the layout
app:horizontal_ratio="2" // ratio of 2:3
app:vertical_ratio="3">
Update
With introduction of ConstraintLayout you don't have to write either a single line of code or use third-parties or rely on PercentFrameLayout which were deprecated in 26.0.0.
Here's the example of how to keep 1:1 aspect ratio for your layout using ConstraintLayout:
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginEnd="0dp"
android:layout_marginStart="0dp"
android:layout_marginTop="0dp"
android:background="#android:color/black"
app:layout_constraintDimensionRatio="H,1:1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
</LinearLayout>
</android.support.constraint.ConstraintLayout>

I've used and liked Jake Wharton's implementation of ImageView (should go similarly for other views), others might enjoy it too:
AspectRatioImageView.java - ImageView that respects an aspect ratio applied to a specific measurement
Nice thing it's styleable in xml already.

Simply override onSizeChanged and calculate ratio there.
Formula for aspect ratio is:
newHeight = original_height / original_width x new_width
this would give you something like that:
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
//3:5 ratio
float RATIO = 5/3;
setLayoutParams(new LayoutParams((int)RATIO * w, w));
}
hope this helps!

The ExoPlayer from Google comes with an AspectRatioFrameLayout that you use like this:
<com.google.android.exoplayer2.ui.AspectRatioFrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:resize_mode="fixed_width">
<!-- https://exoplayer.dev/doc/reference/com/google/android/exoplayer2/ui/AspectRatioFrameLayout.html#RESIZE_MODE_FIXED_WIDTH -->
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent" />
</com.google.android.exoplayer2.ui.AspectRatioFrameLayout>
Then you must set the aspect ratio programmatically:
aspectRatioFrameLayout.setAspectRatio(16f/9f)
Note that you can also set the resize mode programmatically with setResizeMode.
Since you are obviously not going to grab the whole ExoPlayer library for this single class, you can simply copy-paste the file from GitHub to your project (it's open source):
https://github.com/google/ExoPlayer/blob/release-v2/library/ui/src/main/java/com/google/android/exoplayer2/ui/AspectRatioFrameLayout.java
Don't forget to grab the attribute resize_mode too:
https://github.com/google/ExoPlayer/blob/release-v2/library/ui/src/main/res/values/attrs.xml#L18-L25
<attr name="resize_mode" format="enum">
<enum name="fit" value="0"/>
<enum name="fixed_width" value="1"/>
<enum name="fixed_height" value="2"/>
<enum name="fill" value="3"/>
<enum name="zoom" value="4"/>
</attr>

You may find third-party libraries. Instead of using them, use constraint layout.
Below code sets the aspect ratio of ImageView as 16:9 regardless of the screen size and orientation.
<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">
<ImageView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:scaleType="fitXY"
android:src="#drawable/mat3"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0"
app:layout_constraintDimensionRatio="H,16:9"/>
</androidx.constraintlayout.widget.ConstraintLayout>
app:layout_constraintDimensionRatio="H,16:9". Here, height is set with respect to the width of the layout.
For your question, set android:layout_width="match_parent" and use app:layout_constraintDimensionRatio="H,1:1" in your view.

I have used in this way.
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/imageView_home_one"
android:layout_width="0dp"
android:layout_height="0dp"
android:scaleType="centerCrop"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintDimensionRatio="H,4:3"
android:layout_marginTop="#dimen/_5sdp"
android:visibility="gone"
tools:ignore="MissingConstraints" />
</androidx.constraintlayout.widget.ConstraintLayout>