Develop Reference

Align multipile images evenly horizontaly

I have 2 image views in a linear layout like so:
<LinearLayout
style="#style/home_icon_row"
android:orientation="horizontal">
<ImageView
android:id="#+id/ibtn_home_bus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_bus_selector" />
<ImageView
android:id="#+id/ibtn_home_butoday"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_butoday_selector" />
</LinearLayout>
How can i align the two images so that they are evenly placed within the linear layout. Something similar to "justified text" so that it has equal spacing on the left and right of the image from each other and the border of the screen.

it's not the best solution, but it should work:
<LinearLayout
style="#style/home_icon_row"
android:orientation="horizontal">
<View
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="0dp"
android:enable="false"
android:focussable="false"
android:clickable="false"
/>
<ImageView
android:id="#+id/ibtn_home_bus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_bus_selector" />
<View
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="0dp"
android:enable="false"
android:focussable="false"
android:clickable="false" />
<ImageView
android:id="#+id/ibtn_home_butoday"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_butoday_selector" />
<View
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="0dp"
android:enable="false"
android:focussable="false"
android:clickable="false" />
</LinearLayout>
if this is for some kind of landing it's ok but if it's a hard used layout think about implementing it dinamically via javacode to make it faster.
EDIT: i added 3 attributes ( enable, focussable, clickable ) to disable the placehodler view so that they'll be considered only at measures/layout time, but not during events handling.

// try this way here is alternative to use two sub linear layout rather three View.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="#style/home_icon_row"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center">
<ImageView
android:id="#+id/ibtn_home_bus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_bus_selector" />
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center">
<ImageView
android:id="#+id/ibtn_home_butoday"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_butoday_selector" />
</LinearLayout>
</LinearLayout>

You should be able to get similar effect by using layout_width="0dp", layout_weight="1" and scaleType="centerInside" for both ImageViews.
The only difference is that space between the images can be bigger.

<LinearLayout
style="#style/home_icon_row"
android:orientation="horizontal"
android:padding="#dimen/padding">
<ImageView
android:id="#+id/ibtn_home_bus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_bus_selector"
android:layout_marginRight="#dimen/padding"/>
<ImageView
android:id="#+id/ibtn_home_butoday"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ico_butoday_selector" />
</LinearLayout>

Custom dialog height to match content

This is my custom dialog, there are some textboxs and two buttons.
I'm using a RelativeLayout on it.
I'd like the dialog size to match the content, not all that blank space under there.
I don't want to use explicit pixel heights (it's not good practice).
Another thing, there's a way to have some space between every view?
This is my XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:id="#+id/txt_desc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="8pt"
android:textStyle="italic" />
<TextView
android:id="#+id/txt_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_below="#+id/txt_desc"
android:textSize="8pt" />
<TextView
android:id="#+id/txt_place"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_below="#+id/txt_date"
android:textSize="8pt" />
<Button
android:id="#+id/btn_close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="#+id/txt_place"
android:layout_toRightOf="#+id/view"
android:text="#string/btn_close" />
<View
android:id="#+id/view"
android:layout_width="0dp"
android:layout_height="1dp"
android:layout_centerHorizontal="true" />
<Button
android:id="#+id/btn_edit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/txt_place"
android:layout_toLeftOf="#+id/view"
android:drawableLeft="#android:drawable/ic_menu_edit"
android:text="#string/btn_edit" />
</RelativeLayout>

First question
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
Second question
Plus use android:marginTop="5dp" if you want to separate a View from Top for 5 dp.
marginLeft|Right|Bottom are also available.
<TextView
android:id="#+id/txt_place"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginTop="5dp" <-----------------
android:layout_below="#+id/txt_date"
android:textSize="8pt" />
By the way, if I were you, I'd nest some layouts to make order. You can have a general Relative Layout, then 2 linear layouts: one horizontal for TextViews and one vertical for Buttons. You can definely play with your editor and try to make the best appearance for your dialog.
EDIT
Try this one:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#0000"
android:orientation="vertical"
android:paddingBottom="50dp" >
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/txt_desc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="prova"
android:textSize="8pt"
android:textStyle="italic" />
<TextView
android:id="#+id/txt_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:text="prova"
android:textSize="8pt" />
<TextView
android:id="#+id/txt_place"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:text="prova"
android:textSize="8pt" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<Button
android:id="#+id/btn_edit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableLeft="#android:drawable/ic_menu_edit"
android:text="btn_edit" />
<Button
android:id="#+id/btn_close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="btn_close" />
<View
android:id="#+id/view"
android:layout_width="0dp"
android:layout_height="1dp" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
I've hard-coded the texts. The main idea is to use a big container layout in background, which is trasparent (background=#0000) and in top of that a layout in wrap_content containing your Views.
If this solution doesn't resolve your problem, I think you could edit height directly in your code. Try to relate to this question

Set your relative layout's height to wrap_content.
For example:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!-- More XML -->
</RelativeLayout>
Also be aware that fill_parent is deprecated for widths and heights.
You can add either margin (extra space outside a view) or padding (extra space inside a view) with android:layout_margin or android:padding respectively. There are also variants such as layout_marginTop that only apply to a specific side of the view.

Android Arrange widgets in LinearLayout in perfect ratio using layout_weight

In my application I have to arrange my widgets in proper ratio (width). I have 6 widgets and I want to align in the ratio of 2:2:4:4:1:1 considering width only. I tried this one but i am not get the right solution.
<LinearLayout
android:id="#+id/register_header12"
android:layout_width="fill_parent"
android:layout_height="55dp"
android:layout_alignParentBottom="true"
android:layout_marginTop="5dp"
android:weightSum="14"
android:orientation="horizontal" >
<ImageView
android:id="#+id/register_title_image"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="2"
android:contentDescription="#string/app_icon_desc"
android:src="#drawable/logo_blue" />
<TextView
android:id="#+id/register_title_name"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="2"
android:text="Name"
android:textStyle="bold" />
<Button
android:id="#+id/bbb"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#drawable/bar_button"
android:text="BBB"
android:textStyle="bold" />
<Button
android:id="#+id/aaa"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#drawable/bar_button"
android:text="AAA"
android:textStyle="bold" />
<ImageView
android:id="#+id/setting"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="4"
android:src="#drawable/ic_menu_manage"
android:onClick="showSettings"
/>
<ImageView
android:id="#+id/signout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="4"
android:src="#drawable/ic_menu_blocked_user"
android:onClick="doSignOut"
/>
</LinearLayout>
Please provide me the best way..

Change all of your android:layout_widths to 0. That will allow the weight property to determine the width and should solve your problem.

first of all put weightSum=(sum of all layout weight in your case is 14) in your Linear layout,
then make child view width wrap_content and weight attribute as per your ratio.
hope this will work.

layout_weight doesn't decide widget size. In layout, each widget measure its size and require space from parent layout. Then parent assign rest of space to all children according to ratio of layout_weight. So, in your case, you may specify layout_width=0. This way, widgets doesn't require any space, then parent layout could assign space according to layout_weight.

Ralgha's answer is correct one. and for code you can refer below code.
Please check code:
<LinearLayout
android:id="#+id/register_header12"
android:layout_width="fill_parent"
android:layout_height="55dp"
android:layout_alignParentBottom="true"
android:layout_marginTop="5dp"
android:weightSum="14"
android:orientation="horizontal" >
<ImageView
android:id="#+id/register_title_image"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="2"
android:contentDescription="#string/app_icon_desc"
android:src="#drawable/logo_blue" />
<TextView
android:id="#+id/register_title_name"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="2"
android:text="Name"
android:textStyle="bold" />
<Button
android:id="#+id/bbb"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#drawable/bar_button"
android:text="BBB"
android:textStyle="bold" />
<Button
android:id="#+id/aaa"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#drawable/bar_button"
android:text="AAA"
android:textStyle="bold" />
<ImageView
android:id="#+id/setting"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="4"
android:src="#drawable/ic_menu_manage"
android:onClick="showSettings"
/>
<ImageView
android:id="#+id/signout"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="4"
android:src="#drawable/ic_menu_blocked_user"
android:onClick="doSignOut"
/>
</LinearLayout>
Hope this will help you.

Is there a way to offset a view from center?

I'm trying to possition my button not exactly in center, but let's say in the 2/5s of the screen height, I was looking for attribute unsuccessfully, so I tried this approach
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/background"
android:padding="20dp" >
<ImageButton
android:id="#+id/flashlight_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_above="#+id/fakeView"
android:background="#null"
android:contentDescription="#string/flashlight_button_description"
android:src="#drawable/freeml_bright" />
<View
android:id="#+id/fakeView"
android:layout_width="10dp"
android:layout_height="10dp"
android:layout_centerInParent="true"
android:background="#FFAABB" />
</RelativeLayout>
However it does not work, even if I set margin on the fake view.
Padding attribute works, however as it is a big image and if I want it to start at 2/5ths of screen height, it covers the center point of screen, so if I use padding attribute it works but it pushes it away from center and does not allow it to cover it.
Alhough, I made it work using LinearLayout, which I wanted to avoid because there are more Views on top and bottom next to each other so it would lead to nested views using linear layout. Unfortunately I think its the only option.
It basically it uses another linear layout that fills the remaining space left unused by top and bottom views with height=0dp and weight=1 and sets its gravity to center.
<?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"
android:padding="20dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="#string/application_logo_description"
android:src="#drawable/mylight" />
<ImageButton
android:id="#+id/settings_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:background="#null"
android:contentDescription="#string/settings_button_description"
android:src="#drawable/settings_button" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:gravity="center"
android:orientation="vertical" >
<ImageButton
android:id="#+id/flashlight_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#null"
android:contentDescription="#string/flashlight_button_description"
android:src="#drawable/flashlight_button_selector" />
<View
android:id="#+id/fakeView"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginTop="60dp"
android:background="#FFAABB" />
</LinearLayout>
<ImageView
android:id="#+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center_horizontal"
android:contentDescription="#string/powered_by_description"
android:src="#drawable/powered_by" />
<ImageButton
android:id="#+id/ad_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center_horizontal"
android:background="#null"
android:contentDescription="#string/ad_button_description"
android:src="#drawable/freeml" />
</LinearLayout>

Depending on the screen size of the target device, padding by X dp might move it more than just a fifth of the height.
You might have to code this movement yourself. However, nothing prevents you from doing:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/background"
android:padding="20dp" >
<View
android:id="#+id/fakeView"
android:layout_width="10dp"
android:layout_height="10dp"
android:layout_centerInParent="true"
android:background="#FFAABB" />
<ImageButton
android:id="#+id/flashlight_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_above="#+id/fakeView"
android:marginBottom="50dp"
android:background="#null"
android:contentDescription="#string/flashlight_button_description"
android:src="#drawable/freeml_bright" />
</RelativeLayout>

Don't use margin, use padding (top), like so:
<View
android:id="#+id/fakeView"
android:layout_width="10dp"
android:layout_height="10dp"
android:layout_centerInParent="true"
android:paddingTop="80dp"
android:background="#FFAABB" />
That should work, though I've not tested it!

try using attribute android:layout_toLeftOf="#+id/fakeView"

Why is Android lint showing "nested weights are bad for performance" when none are nested?

The layout_weight attribute in the last TextView in this layout is being highlighted by lint as causing bad performance. I suspect the name of the lint warning is erroneous as there are no nested weights. There are several stretching views, and I suspect what it means is dependent weighted views.
What's the solution, to build this layout, and avoid this lint warning, and improve performance?
<?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:gravity="center_horizontal"
android:background="#drawable/background_gradient"
>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/image4"
android:layout_margin="6dp"
android:contentDescription="#string/PLACEHOLDER_TEXT"
/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal"
>
<Button
style="#style/dashboard_button"
android:id="#+id/home_management"
android:text="#string/ICON_MANAGEMENT"
/>
<Button
style="#style/dashboard_button"
android:id="#+id/home_calculators"
android:text="#string/ICON_CALCULATORS"
/>
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal"
>
<Button
style="#style/dashboard_button"
android:id="#+id/home_guidelines"
android:text="#string/ICON_GUIDELINES"
/>
<Button
style="#style/dashboard_button"
android:id="#+id/home_faq"
android:text="#string/ICON_FAQ"
/>
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal"
>
<Button
style="#style/dashboard_button"
android:id="#+id/home_refs"
android:text="#string/ICON_REFERENCES"
/>
<Button
style="#style/dashboard_button"
android:text=""
android:visibility="invisible"
/>
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center_vertical"
android:layout_margin="6dp"
>
<TextView
android:text="#string/HOMEPAGE_CONTENT"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:textStyle="bold"
android:textColor="#FFFFFF"
/>
<View
android:layout_width="8dp"
android:layout_height="1dp"
/>
<ImageView
android:id="#+id/home_logo"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="#drawable/image7"
android:contentDescription="#string/PLACEHOLDER_TEXT"
/>
</LinearLayout>
<Button
android:id="#+id/home_web_site"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/HOMEPAGE_FOOTER"
android:paddingLeft="4dp"
android:paddingRight="4dp"
android:paddingTop="8dp"
android:paddingBottom="8dp"
android:textSize="12sp"
android:background="#drawable/button_red"
android:layout_margin="6dp"
android:textColor="#FFFFFF"
/>
</LinearLayout>

You don't need to worry about this, however, especially if you really need the weights, and if that's the only way to declare your layout properly.

The TextView and ImageView in your #string/HOMEPAGE_CONTENT area are nested in their parent LinearLayout and have weights assigned. I suspect those are your problem, especially since the parent is wrap_content, so theoretically there shouldn't be any space for the child elements to stretch into.

Concerning this part of code.
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="horizontal"
<Button
style="#style/dashboard_button"
android:id="#+id/home_management"
android:text="#string/ICON_MANAGEMENT"
/>
<Button
style="#style/dashboard_button"
android:id="#+id/home_calculators"
android:text="#string/ICON_CALCULATORS"
/>
Your LinearLayout contains "layout_weight" attribute, and if the style "dashboard_button" contains the attribute "layout_weight" too, then you got couple of nested views with the "layout_weight" attribute, though the lint doesn't warn me now concerning "layout_weight" inside the styles.
My solution is to substitue one(or both) of the LinearLayouts with RelativLayout and adjust the sizes and places programmatically.