Develop Reference

Android Grey Out LinearLayout

I have a linear layout which contains a set of child views (mixture of text, images and other layouts).
I want to grey out the linear layout and all the child views so they look disabled (similar to how a button works).
Is this possible to achieve? I know i can set a colour filter when painting on the canvas, is there something similar for layouts?

Another way is to call setEnabled() on each child (for example if you want to do some extra check on child before disabling), check out this answer:
https://stackoverflow.com/a/7069377/4840812

You can use Frame-layout
Using TEST ONE you can achieve above text view like disabled. You can set root layout clickable false for actually disable views inside layout.
TEST TWO is for understanding purpose. Like you need to manage order of view to show effect.
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!--THIS IS TEST ONE-->
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_marginTop="150dp"
android:background="#000000"
android:gravity="center"
android:text="TEST DATA"
android:textColor="#android:color/white"
android:textSize="30sp" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="200dp"
android:background="#DAD6D6D6"
android:gravity="center"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Data"
android:textColor="#color/colorAccent"
android:textSize="30sp" />
</LinearLayout>
<!--THIS IS TEST TWO-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="200dp"
android:layout_marginTop="300dp"
android:background="#DAD6D6D6"
android:gravity="center"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Data"
android:textColor="#color/colorAccent"
android:textSize="30sp" />
</LinearLayout>
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_marginTop="400dp"
android:background="#000000"
android:gravity="center"
android:text="TEST DATA"
android:textColor="#android:color/white"
android:textSize="30dp" />
</FrameLayout>

To achieve your layout you can use the RelativeLayout. In RelativeLayout you can use the 2 different views or LinearLayout. In first layout you can add views according to your need, and In second layout you can set the alpha colorcode for disable the layout.
Please try below code:
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerInParent="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/demo_img_1" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/demo_img_1"
android:layout_marginLeft="20dp"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/trans"/>
</RelativeLayout>
Here is output for code:

Android layout anomaly - actual layout not complying with Android Studio appearance.

I am trying to write an application with two separate views of graphical data - one as an X-Y graph. and the other an X vs T graph. I want the two to be arranged vertically, with the X-Y graph on top. I have written an extension to the View class which manages the plotting, and that is not the problem.
I initially used a RelativeLayout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:custom="http://schemas.android.com/apk/res-auto"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/content_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#CCCCFF"
android:orientation="vertical"
android:gravity="center_horizontal">
<RelativeLayout
android:id="#+id/button_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="clearCanvas"
android:text="#string/btn1Text"
style="#android:style/Widget.Button" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="startPlot"
android:text="#string/btn2Text"
android:layout_toRightOf="#id/button1"
style="#android:style/Widget.Button" />
</RelativeLayout>
<co.android.bmd.chaoswithtime.CanvasView
android:id="#+id/plot_canvas"
android:layout_width="1000px"
android:layout_height="1000px"
android:textColor="#FFFFFF" />
<co.android.bmd.chaoswithtime.CanvasView
android:id="#+id/trend_canvas"
android:textColor="#FFFFFF"
tools:layout_below="#id/plot_canvas"
android:layout_height="500px"
android:layout_width="1000px" />
</RelativeLayout
According to the layout shown in Android Studio, this should give the required result:
X-T view overlaying the XY view:
I've tried a number of variants to get the alignment sorted out, but the only way to do it was to add a hefty top margin to the X-T view - not very satisfactory.
I can get what I want using a LinearLayout, but cannot figure out why the Relativelayout does not work (and why there is a difference between the preview in Android Studio and the emulated result from the same package. (The emulated result actually comes up on the real device as well.)
Can anyone come up with an explanation?

You have passed width and height in pixels, that means it's content and when you run your code it takes only 1000 pixels in screen.
Better is that you should use LinearLayout as parent of your custom view and use weight and weightSum. And pass match_parent width and height to LinearLayout.
you can try with below xml. this could help you.
<?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:custom="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/content_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#CCCCFF"
android:gravity="center_horizontal"
android:orientation="vertical">
<RelativeLayout
android:id="#+id/button_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
<Button
android:id="#+id/button1"
style="#android:style/Widget.Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="clearCanvas"
android:text="#string/btn1Text" />
<Button
android:id="#+id/button2"
style="#android:style/Widget.Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/button1"
android:onClick="startPlot"
android:text="#string/btn2Text" />
</RelativeLayout>
<LinearLayout
android:layout_below="#+id/button_bar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="3">
<co.android.bmd.chaoswithtime.CanvasView
android:id="#+id/plot_canvas"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:textColor="#FFFFFF" />
<co.android.bmd.chaoswithtime.CanvasView
android:id="#+id/trend_canvas"
android:layout_height="0dp"
android:layout_weight="2"
android:textColor="#FFFFFF"
tools:layout_below="#id/plot_canvas"1
android:layout_width="match_parent" />
</LinearLayout>
</RelativeLayout

One of two Android ListView filling too much space

I would like to obtain this layout for an Android app for mobile phones:
Icon - Object1
List with entries related to Object1
Icon - Object2
List with entries related to Object2
So far I have used the following layout tree (edited graphically with the editor in Android Studio):
Root-LinearLayout
Vertical LinearLayout
Horizontal LinearLayout with icon and text
ListView
Vertical LinearLayout
Horizontal LinearLayout with icon and text
ListView
May be this is not the best way to organize such layout (may be I should use lists with header, but suggestions very welcome), however it can be a good case for understanding deeper how ListView works.
This is the graphical layout generated:
the blue row corresponds to the first LinearLayout. As you can see from the second screenshot that follows, the second list goes all the way down to Hell, bringing me with her. Is there any way to make the lists respect the wrap_content+ weight behaviour?
The XML code follows. I have tried several combos (both reasonable and unreasonable) of layout:weights but none works. I also tried to set the min-width of the first LinearLayout (the hidden one), but nothing changes.
Could you please help me?
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="2">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1">
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:minHeight="50dp">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageView15"
android:src="#drawable/abc_ic_menu_share_mtrl_alpha" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Object1"
android:id="#+id/textView24"
android:textSize="26dp"
android:paddingLeft="10dp" />
</LinearLayout>
</LinearLayout>
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/listView2"
android:layout_weight="1" />
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1">
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageView16"
android:src="#drawable/abc_ic_commit_search_api_mtrl_alpha" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Object2"
android:id="#+id/textView25"
android:textSize="26dp"
android:paddingLeft="10dp" />
</LinearLayout>
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/listView"
android:layout_weight="1" />
</LinearLayout>

It should work if you put your ListViews inside of the child LinearLayouts which hold the LinearLayout that has the TextView and ImageView. You also should be using "0dp" for the height when using weight with a vertical layout.
Something like this, I believe, should work
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="2">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1">
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:gravity="center_vertical"
android:minHeight="50dp"
android:layout_weight=".2">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageView15"
android:src="#drawable/abc_ic_menu_share_mtrl_alpha" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Object1"
android:id="#+id/textView24"
android:textSize="26dp"
android:paddingLeft="10dp" />
</LinearLayout>
<ListView
android:layout_width="wrap_content"
android:layout_height="0dp"
android:id="#+id/listView2"
android:layout_weight=".8" />
</LinearLayout>
Note the other changes: I gave the inner-LinearLayout an arbitrary weight of ".2" then the ListView a weight of ".8". And, of course, set the height to "0dp". You may need to play with those weights a bit but I think doing something like that for both first child LinearLayouts should get you close.
That may get your current layout to work but using headers and/or an ExpandableListView may be a better option.

Android ScrollView and buttons at bottom of the screen

I want to implement this: A ScrollView that contains many elements (ImageViews, TextViews, EditTexts etc) and then after the ScrollView some buttons (which are custom ImageViews) that appear always exactly at the bottom of the screen.
If I use the android:fillViewport="true" attribute, then if the elements of the ScrollView are too big to fit in the screen size the buttons get invisible . If I use the android:Weight=1 attribute then the ScrollView gets only 50% of the Screen when the screen is big and it can fit (I want the buttons to take a small percentage, about 10%). If I set the android:Weight to bigger values then the buttons appear very small.
Please help! Maybe it is something simple that I overlooked but I’ve been banging my head for hours!

Just created and tested it. Looks like you want.
<?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="match_parent">
<LinearLayout
android:id="#+id/buttons"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center"
android:layout_alignParentBottom="true">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Custom Button1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Custom Button2"/>
</LinearLayout>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#id/buttons">
<!--Scrollable content here-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="test text"
android:textSize="40dp"/>
</LinearLayout>
</ScrollView>
</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hallo Welt"
/>
</LinearLayout>
</ScrollView>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Go next page"
android:layout_alignParentRight="true" />
</RelativeLayout>
</LinearLayout>

This worked for me. Give the scroll view a weight of 1. Put all the other widgets following the scroll view in a layout. The scroll view will grow enough to not block the rest.
Widgets in scroll view and rest at bottom

scrollview cannot fit the screen because you put it on a linear layout, so linear layout fit in the screen,
just try to make scrollview as root elemen on xml layout
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<!-- Here you can put some XML stuff and BOOM! your screen fit to scrollview -->
</LinearLayout>
</ScrollView>

If you do not want to use RelativeLayout, it is better to use LinearLayout. This method is better in my opinion.
Just set the layout_weight to one

Android: How can you align a button at the bottom and listview above?

I want to have a button at the bottom of the listview.
If I use relativeLayout/FrameLayout, it aligns but listView goes down to very botton.
(Behind the button at the bottom)
FrameLayout:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
<FrameLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/btnButton"
android:text="Hello"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</FrameLayout>
</FrameLayout>
RelativeLayout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/btnButton"
android:text="Hello"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</RelativeLayout>
</RelativeLayout>
Above two codes only work like the first image. What I want is second image.
Can anybody help?
Thank you.

A FrameLayouts purpose is to overlay things on top of each other. This is not what you want.
In your RelativeLayout example you set the ListViews height and width to MATCH_PARENT this is going to make it take up the same amount of space as its parent, and thus take up all of the space on the page (and covers the button).
Try something like:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ListView
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0"/>
</LinearLayout>
The layout_weight dictates how the extra space is to be used. The Button does not want to stretch beyond the space it requires, so it has a weight of 0. The ListView wants to take up all of the extra space, so it has a weight of 1.
You could accomplish something similar using a RelativeLayout, but if it is just these two items then I think a LinearLayout is simpler.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff"
>
<ListView android:id="#+id/ListView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1">
</ListView>
<FrameLayout android:id="#+id/FrameLayout01"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<Button android:id="#+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
android:layout_gravity="center_horizontal">
</Button>
</FrameLayout>
</LinearLayout>
Here is the design you are looking for.
Try it.

I needed two buttons side-by-side at the bottom. I used a horizontal linear layout, but assigning android:layout_height="0dp" and android:layout_weight="0" for the buttons' linear layout didn't work. Assigning android:layout_height="wrap_content" for just the buttons' linear layout did. Here's my working layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/new_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="New" />
<Button
android:id="#+id/suggest_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Suggest" />
</LinearLayout>
</LinearLayout>

RelativeLayout will ignore its children android:layout_width or android:layout_height attributes, if the children have attributes that properly define their left and right or top and bottom values, respectively.
To achieve the result on the right image, showing the list above the button, your layout should look like this:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#android:id/button1"
android:layout_alignParentTop="true"/>
<Button
android:id="#android:id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="#android:string/ok"/>
</RelativeLayout>
The key is to define android:layout_alignParentTop (defines top value) and android:layout_above (defines bottom value) in your RecyclerView. This way, RelativeLayout will ignore android:layout_height="match_parent", and the RecyclerView will be placed above the Button.
Also, make sure you look into android:layout_alignWithParentIfMissing, if you have a more complex layout and you still need to define these values.

I am using Xamarin Android, and my requirement is exactly the same as William T. Mallard, above, i.e. a ListView with 2 side-by-side buttons under it.
The solution is this answer didn't work in Xamarin Studio however - when I set the height of the ListView to "0dp", the ListView simply disappeared.
My working Xamarin Android code is as follows:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/ListView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_above="#+id/ButtonsLinearLayout" />
<LinearLayout
android:id="#id/ButtonsLinearLayout"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:orientation="horizontal"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/Button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
<Button
android:id="#+id/Button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
</LinearLayout>
</RelativeLayout>
I aligned ButtonsLinearLayout to the bottom of the screen, and set the ListView to be above ButtonsLinearLayout.

#jclova one more thing you can do is use layout-below=#+id/listviewid in relative layout

In your relative layout height of listview is match_parent which is fill_parent(for 2.1 and older) so best solution is if you want to use relative layout then first Declare your button then your list view, make list view position as above your button id, If you want button always at bottom then make it alignParentBottom..
Snippet is
<RelativeLayout
android:layout_width="fill_parent" android:layout_height="fill_parent"
android:id="#+id/rl1"><Button
android:layout_width="MATCH_PARENT"
android:layout_height="WRAP_CONTENT"
/><ListView
android:layout_width="MATCH_PARENT"
android:layout_height="0"
android:layout_above="#id/listview"/></RelativeLayout>
This prevents your list view taking whole place and make your button appear..

This will be the best and the most simple solution to the problem. Just add android:layout_above="#id/nameOfId" in the layout that you want to move above with respect to that layout.
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.sumeru.commons.activity.CommonDocumentUploadActivity">
<ListView
android:id="#+id/documentList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="#id/verifyOtp" />
<com.sumeru.commons.helper.CustomButton
android:id="#+id/verifyOtp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="#string/otp_verification" />
</RelativeLayout>