Develop Reference

ConstraintLayout spacing between weighted Views?

I am trying to build an Android UI where I need 7 boxes with the days of the week. In order to do this, I decided to go with a ConstraintLayout in order to be able to auto resize my views on any screen.
I created a chain between all 7 views with the with the "spread_inside" attribute, with worked but since I had my views' widths set to wrap_content, due to the nature of TextViews the views did not have equal widths. So I tried making them have equal widths by setting all of 7 views' widths to 0dp. This works but leaves no space between the views. Is there a way to add some spacing between these 7 views? Or is there another way of achieving the "equal widths" to all 7 views while keeping the auto-resizing ability on any screen? Is this even possible with ConstraintLayout or should I keep using LinearLayout for this kind of things? (as seen in the last screenshot)
I want my views to shrink when the screen is small and to expand up to a level when the screen is big. Please see the screenshots below of how it looks now. I want to add an 8dp padding between each view (on a LinearLayout I achieve this by adding a transparent divider on the layout with 8dp width, as in the last screenshot)
How it should look, achieved using LinearLayout

if you want them to be all the same width you don't even need spread_inside, just set the width to 0dp and then add margins to the views. for example:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<View
android:id="#+id/view1"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_marginRight="4dp"
android:layout_marginLeft="8dp"
android:background="#ffff0000"
app:layout_constraintEnd_toStartOf="#+id/view2"
app:layout_constraintStart_toStartOf="parent"/>
<View
android:id="#+id/view2"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_marginRight="8dp"
android:layout_marginLeft="4dp"
android:background="#ff00ff00"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/view1"/>
</android.support.constraint.ConstraintLayout>
keep in mind that space between views will be the sum of 2 margins, first and last view will have only 1 margin space, so you need to set them accordingly (like 4dp for margins between views and 8dp for first and last margin)

Views in my recyclerView is not in center on all phones?

I have a very irritating problem with my views. As you see on a galaxy S7 my views is perfectly in center, but on a galaxy S4 mini they are placed down at the bottom!
I have tried to change alot in XML without any succses. I think it may be of the way I designet the whole thing with recyclerview, tabviews etc.
The following dont work either:
layout_InParent, Gravity:Center, layout_centerVertical
Imagebutton item for the recyclerview. item_colorbutton.xml:
android:id="#+id/colorbutton"
android:layout_width="48dp"
android:layout_height="48dp"
android:layout_margin="15dp"
android:background="#drawable/bbtn">
BACKGROUND tabfragement. tab_fragment_1.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.RecyclerView
android:layout_marginTop="10dp"
android:id="#+id/rvColors"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
This is the viewpager for the different tabs: BACKGROUND, FONT, TEXT STYLE
<org.m.muddzboy.QuoteCreator.ViewPager.NonSwipeableViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="51pt"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_centerInParent="true"
android:background="#517293" />

Your parent view seems to be limited height... and your recyclerview wraps children, plus it has top margin of 10dp. So you have 10dp, then 15dp + 15dp top and bottom margin of child view (you set general margin of 15dp, so all sides), plus 48dp height of child view. Seems like on low density devices that is not enough for your view which contains recyclerview. So it follows the rules and pushes your views down. It cannot break set margin. It has to set them as you requested.
In situations like this it's better to have dimensions for different device configurations. And if it's too complex, setting relative dimensions programmatically based on measured height of containing view.

RelativeLayout takes all its space, even though I've set its height to "wrap_content"

Background
I have a RelativeLayout inside a FrameLayout/RelativeLayout (doesn't matter to me), which should be at the bottom of the screen (like a toolbar), and should hold a few views in it.
Its height is set to "wrap_content" and so does its child-views.
The child-views of this layout are : A textView that is on the left, and a Horizontal LinearLayout on the right with a few buttons.
The problem
It seems that no matter what I do, the textview is causing the RelativeLayout to take the whole space, instead of just its children.
The code
Here's the minimal XML content that causes this problem. I've removed the extra stuff (LinearLayout and its children, and also some attributes that don't matter) since they don't cause this problem in case I remove the TextView:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FF000000" >
<!-- Here I've put some views that don't have any relation with the views below, so it doesn't have anything with do with the problem -->
<RelativeLayout
android:id="#+id/RelativeLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="#drawable/vertical_gradient_transparent_to_black" >
<!-- Here I've put a LinearLayout that doesn't cause the problem, so I've removed it for simplicity-->
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"/>
</RelativeLayout>
</RelativeLayout>
I've tried many possible attributes, and also tried adding additional layouts to try to "fool" the RelativeLayout, but none of those have succeeded.
The question
Why does it occur?
A working solution would be to use a Horizontal LinearLayout (with a weight for the TextView ) instead RelativeLayout , but I still want to know why can't I use a RelativeLayout, and why it occurs. Also how to fix it while still using RelativeLayout.

From the RelativeLayout doc:
Class Overview
A Layout where the positions of the children can be described in relation to each other or to the parent.
Note that you cannot have a circular dependency between the size of the RelativeLayout and the position of its children. For example, you cannot have a RelativeLayout whose height is set to WRAP_CONTENT and a child set to ALIGN_PARENT_BOTTOM
Class documentation
Which is exactly your case. RelativeLayout can not do that.

I have encountered the same issue before, this might be caused by android:layout_alignParentBottom attribute.Maybe you can find another way to achieve your desired effect. See this for more information.

This is some kind of Strange issue. Maybe someone else has the explanation.
I found it working when i removed the line
android:layout_alignParentBottom="true"/>
and it also worked when i tried some like this
<TextView
android:layout_width="match_parent"
android:layout_alignParentTop="true"
android:layout_height="wrap_content"/>

Android RelativeLayout and height of wrap_content?

I am trying to make a selection ListActivity, similar to the one used to add shortcuts to the launcher screens. I have rolled my own header and footers, which I would like to be "sticky" at the top and bottom of the view when on screen. In order to do this, I am using a RelativeLayout with the header set to dock to top, footer set to dock to bottom, and the list set to go below the header and above the footer. In terms of the overall layout of the activity, this is rendering as I would expect. The header is sticky to the top, the footer is sticky to the bottom, and the list scrolls in between them.
One odd thing though happened when I switched to the RelativeLayout as my root. Please see the following screenshot:
I want my Activity's height to be wrap_content, so that the form is only as high as the content displayed in it, but once i switched to RelativeLayout, it seems to render the Activity effectively as fill_parent, taking up the whole screen, even though the content doesn't warrant it. Notice that there are not enough list items to fill the screen, which with the fill_parent style, is leaving a bunch of whitespace between the end of the list, and the footer. I was setting my height's via styles - which worked fine with LinearLayout, but seems to be ignored now. So I tried hard-coding the height directly on the RelativeLayout, but it still doesn't work and still renders as fill_parent.
Here is my layout code:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="#style/GroupsList"
android:layout_height="wrap_content">
<FrameLayout android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:id="#+id/hdrGroups"
android:layout_alignParentTop="true">
<include layout="#layout/title"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</include>
</FrameLayout>
<FrameLayout style="#style/MyFooter"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_alignParentBottom="true"
android:id="#+id/ftrGroups">
<ImageView style="#style/CloseButton"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:src="#drawable/add"
android:id="#+id/imgGroupsAdd"
android:clickable="true">
</ImageView>
</FrameLayout>
<ListView android:divider="#9f9f9f"
android:id="#+id/android:list"
android:choiceMode="singleChoice"
android:dividerHeight="1dp"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_below="#id/hdrGroups"
android:layout_above="#id/ftrGroups">
</ListView>
<TextView android:text="#string/browser_no_groups"
style="#style/ListedItemB"
android:id="#+id/android:empty"
android:layout_height="wrap_content"
android:layout_above="#id/ftrGroups"
android:layout_below="#id/hdrGroups"
android:layout_width="fill_parent">
</TextView>
</RelativeLayout>
All layout is done via XML, ... I am not doing any layout in code.
How can I get the sticky header and footer while also having the activity as a whole behave in a wrap_content mode for its height? Is there some other way I should be going about this instead of a RelativeLayout?

According to the developer documentation your desired behaviour is not possible for Relative layout ;
"Note that you cannot have a circular dependency between the size of
the RelativeLayout and the position of its children. For example, you
cannot have a RelativeLayout whose height is set to WRAP_CONTENT and a
child set to ALIGN_PARENT_BOTTOM."
RelativeLayout
To solve your problem you could maybe try to use a linear layout, set to wrap_content and set max height via code to screen height.
You can get the screen height as described here : get screen height

I just change my RelativeLayout in FrameLayout and all starts to work

How to wrap content views rather than background drawable?

How can I get a LinearLayout (or any other ViewGroup) to assume the size of it's child views rather than assuming the size of the background image?
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/large_image300x300pix">
<TextView android:id="#+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello world!"/>
</LinearLayout>
The linear layout becomes the same size as the background image.
How can I get my linear layout to assume the same size as the textview?

OK, so this thread is a little old, but I have a solution that someone might someday find useful. I think Android has problems scaling large images down, so the LinearLayout size ends up getting bumped by the background drawable bitmap, and the ImageView ends up forcing up the size of the parent container.
Unless you use a relative layout. You can make the ImageView relative to the position of the LinearLayout, even when the ImageView is behind the layout in the parent. My solution looks something like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:src="#drawable/activation_popup"
android:scaleType="fitXY"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_alignTop="#+id/activation_layout"
android:layout_alignBottom="#id/activation_layout"
android:layout_alignLeft="#id/activation_layout"
android:layout_alignRight="#id/activation_layout"
android:contentDescription="#string/act_code_label" />
<LinearLayout
android:id="#id/activation_layout"
android:clipToPadding="true"
android:padding="25dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<!-- LinearLayout wraps a bunch of smallish views here -->
</LinearLayout>
</RelativeLayout>
I tried this on a top of display sizes and OS versions, seems to work great. Note that the padding in the LinearLayout is a trick to make space for a shadow border in the background image graphic. The LinearLayout doesn't need any relative positioning because top left is assumed.

You can create a FrameLayout and put an ImageView and your LinearLayout there. So you'll be able to configure the layout of your background image.

This happens because the Android view calculates its minimum size based on its background drawable size.
Check my answer here in this another post which covers the same problem which will help you to achieve your layout configuration.

If your image lends itself to being converted to a scalable 9-patch image, then doing that would cause the background to scale around the TextView.

I believe the best solution here is to set android:clipToPadding="true". What this does is excludes the padding for the main layout and wraps your layout to its children.