Develop Reference

when i'm creating a button it become different size in different mobiles why...?

i'm new to the android when i'm creating the button it's become variation in different mobiles please help me.
<LinearLayout android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_gravity="center_horizontal">
<Button
android:layout_width="wrap_content"
android:gravity="center"
android:width="300sp"
android:layout_height="wrap_content"
android:text="chennai to coimbatore"/>
</RelativeLayout>
</LinearLayout>

construct your button like below. Remove android:width="300sp", It is not needed:
<LinearLayout android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_gravity="center_horizontal">
<Button
android:layout_width="300dp"
android:gravity="center"
android:layout_height="wrap_content"
android:text="chennai to coimbatore"/>
</RelativeLayout>
</LinearLayout>

You are using the sp unit which is device independent BUT is scaled with the user's font size preference
Just use dp instead

different mobile have a different density so that you button like small medium as per density

Use dp instead of sp.
As per documentation
(https://developer.android.com/guide/practices/screens_support.html)
"you should prefer the sp (scale-independent pixel) to define text sizes. The sp scale factor depends on a user setting and the system scales "

How to calculate image size for different devices dpi

I have a listview layout with images
It looks like this
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:layout_width="match_parent"
android:layout_height="240dp"
android:adjustViewBounds="true"
android:id="#+id/listview_item_imageView"
android:layout_gravity="center_horizontal|top" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#FAC308"
android:id="#+id/listview_item_title"
android:text="TITLE"
android:textSize="20sp"
android:paddingBottom="40dp"
android:layout_centerInParent="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#ffffff"
android:id="#+id/listview_item_subtitle"
android:paddingTop="40dp"
android:text="SUBTITLE"
android:textSize="20sp"
android:layout_centerInParent="true" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/orangeSeparator"
android:src="#drawable/orangeseparator"
android:layout_centerInParent="true" />
If I run it on device with 720x1280 240dpi it looks like this
If I run it on device with 720x1280 320dpi it looks like this
I get images from the internet, so I cant prepare different versions.
How to make it look similar across all the devices ?

You can use fitXY Android Developer,
android:scaleType="fitXY"
or you can also create different drawable resources from the original one, with Photoshop or any similar program

in your container you have
android:layout_height="match_parent"
and in the image:
android:layout_height="240dp"
you have to have the same height or 'wrap_content' for your container not to have those gaps.
you can also add to the imageview:
android:scaleType="centerCrop"
another thing is that you can use specific library to handle loading of network images.

You can look this article . Make your app supporting different dpi variations and different screen types: Supporting Different Screens

why the design of user interface change in different emulator in android studio?

I'm begin to learning android programming and I did not know much about this language
I write a program. I do not know why when I see my user interface it is good but when I run it with different emulators , each emulator show it in different way
enter code here : <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:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context="com.example.faezeh.homework2.MainActivity"
android:orientation="vertical"
>
<TextView android:text="تمرین دوم"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textSize="50sp"
android:textColor="#ff4400"
android:paddingTop="30dp"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="مدیریت یادداشت"
android:layout_gravity="center_horizontal"
android:textSize="40sp"
android:textColor="#000000"
android:paddingTop="30dp"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="تاریخ : 1393/12/26"
android:layout_gravity="center_horizontal"
android:textSize="40sp"
android:textColor="#000000"
android:paddingTop="30dp"
/>
<Button
android:id="#+id/theList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="فهرست یادداشت ها"
android:textSize="30sp"
android:textColor="#000000"
android:background="#00ffff"
android:layout_gravity="center_horizontal"
android:layout_marginTop="30dp"
/>
<Button
android:id="#+id/search"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="جستجوی یادداشت "
android:textSize="30sp"
android:textColor="#000000"
android:background="#00ffff"
android:layout_marginTop="10dp"
android:layout_gravity="center_horizontal"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:gravity="bottom"
>
<Button
android:id="#+id/aboutUs"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="درباره ما"
android:textSize="35sp"
android:textColor="#000000"
android:background="#00ffff"
android:layout_gravity="left|bottom"
/>
<Button
android:id="#+id/setting"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="تنظیمات"
android:textSize="35sp"
android:textColor="#000000"
android:background="#00ffff"
android:layout_gravity="right|bottom"
/>
</LinearLayout>

try to see this thing in your eclipse then your user interface will never change.
you can convert Activity check at here is schreen size 15 schreen sizes are given here to check all android device follow these size once

Since android is available for various types of devices, here I am saying the screen size of the device. So every device comes under certain category with their corresponding screen size, these category are probably LDPI, MDPI, HDPI, XHDPI and XXHDPI. So the design we do usually varies among different screen size.
For detail information regarding the multiple screen size in android and how to handle it, do visit:
http://developer.android.com/guide/practices/screens_support.html
what i have to do to fix this? for example nexus one and nexus 5 show
my program in different way . what i have to do to both of them show
it in right way? – faezeh 1 hour ago
Well for this case you have to particularly design your screens in such a way that it optimize all the screen size. For this here are some key design parameters you should look on:
use textAppearnce instead of textSize property like :
android:textAppearance="?android:attr/textAppearanceLarge"
Try to hard code your controls specially buttons, as dp automatically resize according to the screen size of device.
Try to use layout_weight property in your design.
If you follow this basic guideline, then there will be no problem.
Cheers

How to make layouts grow and shrink?

I'm playing around with making a random recipe collection app.
Now I came across a problem: at the moment I have designed it with my mobile's resolution in mind. But what if the app is used on a device with larger resolution eg. a tablet.
What I want to achieve is that I want the buttons to grow shrink depending on the resolution. For example: when holding my phone vertically, there are 2 columns of buttons. When holding it horizontally, there still are 2 columns, but the view gets wider. Then there should be 4 columns to fill as much of the white space as possible.
Two pictures to illustrate my thoughts:
vertical
horizontal with 2 more columns
My code:
<?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:background="#ffcc33"
android:orientation="vertical"
android:paddingTop="10dp"
android:paddingLeft="10dp"
android:paddingRight="10dp" >
<LinearLayout android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:weightSum="1000" >
<EditText
android:id="#+id/search_box"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:layout_weight="1000"
android:ems="5"
android:hint="#string/search_hint" />
<Button
android:id="#+id/search_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="#string/search_button" />
</LinearLayout>
<ScrollView android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center" >
<RelativeLayout
android:layout_width="225dp"
android:layout_height="wrap_content"
android:layout_below="#+id/search_box"
android:layout_gravity="center"
android:layout_marginTop="15dp" >
<Button
android:id="#+id/btn_lihatoidud"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#android:color/transparent"
android:drawableTop="#drawable/lihatoidud"
android:layout_alignParentTop="true"
android:text="Lihatoidud"
android:textSize="18sp" />
<Button
android:id="#+id/btn_kypsetised"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btn_lihatoidud"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/kypsetised"
android:text="Küpsetised"
android:textSize="18sp" />
<Button
android:id="#+id/btn_seenetoidud"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btn_kypsetised"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/seenetoidud"
android:text="Seenetoidud"
android:textSize="18sp" />
<Button
android:id="#+id/btn_juustutoidud"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btn_seenetoidud"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/juustutoidud"
android:text="Juustutoidud"
android:textSize="18sp" />
<Button
android:id="#+id/btn_lisandid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btn_juustutoidud"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/lisandid"
android:text="Lisandid"
android:textSize="18sp" />
<Button
android:id="#+id/btn_supid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:background="#android:color/transparent"
android:drawableTop="#drawable/supid"
android:text="Supid"
android:textSize="18sp" />
<Button
android:id="#+id/btn_voileivad"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="#+id/btn_supid"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/voileivad"
android:text="Võileivad"
android:textSize="18sp" />
<Button
android:id="#+id/btn_pudrud"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="#+id/btn_voileivad"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/pudrud"
android:text="Pudrud"
android:textSize="18sp" />
<Button
android:id="#+id/btn_joogid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="#+id/btn_pudrud"
android:layout_marginTop="15dp"
android:background="#android:color/transparent"
android:drawableTop="#drawable/joogid"
android:text="Joogid"
android:textSize="18sp" />
</RelativeLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>

Android has a few mechanisms for dealing with this kind of thing. For most people simply having a different layout for different classes of device will be sufficient. i.e:
res/
layout/
my_layout.xml
layout-land/ # landscape
my_layout.xml
layout-sw600dp # bigger devices
my_layout.xml
layout-sw600dp-land # Big and landscape
Android will automatically pick the right layout on the device your app gets loaded on. See the Developer Guide for details there. Alternatively, you might need to define your own custom view that resizes your grid based on the available size. An example of this is a CellLayout, a class written for the grid of apps in Launcher

I would actually reccomend you use the GridView pattern.
https://developer.android.com/guide/topics/ui/layout/gridview.html
Benfits include
Easily customize able if you need multiple rows/columns
Faster performance because you re-use a lot the same views. Scales much better than scrollview approach
Here example with two column for Phones
Here example with four column for tablets
All changing only the number of columns the grid should show. The best way to do this by what "JRaymond" recommended, by having multiple values resposnes depending on if its a tablet/phone. Example
->values ->attrs_arin_view.xml
->values-land->attrs_arin_view.xml
->values-sw600dp -> attrs_arin_view.xml
inside values ->attrs_arin_view.xml
<resources>
<integer name="number_of_column">2</integer>
</resources>
and then change in the values-land to have number_of_column to 4.
Then in your in your xml you mention the integer once
<?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"
>
<GridView
android:id="#+id/gridView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:horizontalSpacing="8dp"
android:numColumns="#integer/number_of_column"
android:padding="8dp"
tools:listitem="#layout/grid_cell_note"
>
</GridView>
</LinearLayout>

You need to create xml files for different screen sizes
http://developer.android.com/guide/practices/screens_support.html
design your XML files to use references instead of hardcoded strings. You can then assign a reference to layouts, buttons and so on which has a different value depending on screen sizes.
(use android:padding="#dimen/pagepadding" instead of android:padding="16dp" and define the dp in values/dimens.xml like this: <dimen name="pagepadding">16dp</dimen>)
To do that you have to create new folders in your Project like values-sw600dp for devices with 600dp smallest width (like Nexus 7 I believe) or values-sw720dp-land for devices with the smallest width of 720dp (10 inch tablets I believe) in landscape.
Do some reading on the developer page and on the internet for that. It's not too difficult

Same layout looks different on a Samsung Galaxy Tab

I'm developing an Android 2.2.2 application which will support multiple screens sizes and all screens will be portrait. I won't support landscape.
I have test the following layout on an HTC Desire and on a Samsung Galaxy Tab 7.7.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/mainLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#drawable/no_conectado"
android:orientation="vertical" >
<TextView
android:id="#+id/labelSelGateName"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:layout_marginTop="80dp" />
<TextView
android:id="#+id/labelSelOpened"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<ProgressBar
android:id="#+id/indicatorActivityView"
android:layout_width="20dp"
android:layout_height="20dp"
android:layout_marginTop="22dp"
android:layout_gravity="center_horizontal" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="110dp"
android:layout_marginTop="60dp"
android:orientation="horizontal" >
<ImageButton
android:id="#+id/btnMyGates"
android:layout_width="50dp"
android:layout_height="110dp"
android:layout_marginLeft="20dp"
android:layout_weight=".33"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onGateClick" />
<LinearLayout
android:layout_width="90dp"
android:layout_height="110dp"
android:layout_weight=".33"
android:orientation="vertical" >
<ImageButton
android:id="#+id/btnOpen"
android:layout_width="90dp"
android:layout_height="55dp"
android:layout_gravity="center_horizontal"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onOpenDoorClick" />
<ImageButton
android:id="#+id/btnClose"
android:layout_width="90dp"
android:layout_height="50dp"
android:layout_gravity="center_horizontal"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onCloseDoorClick" />
</LinearLayout>
<ImageButton
android:id="#+id/btnOptions"
android:layout_width="50dp"
android:layout_height="110dp"
android:layout_marginRight="20dp"
android:layout_weight=".33"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onOptionClick" />
</LinearLayout>
<ImageButton
android:id="#+id/btnFaqs"
android:layout_width="110dp"
android:layout_height="60dp"
android:layout_gravity="center_horizontal"
android:layout_marginTop="10dp"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onFAQClick" />
<ImageButton
android:id="#+id/btnInfo"
android:layout_width="110dp"
android:layout_height="60dp"
android:layout_gravity="right"
android:layout_marginTop="20dp"
android:background="#null"
android:contentDescription="#string/layout_empty"
android:onClick="onInfoClick" />
</LinearLayout>
I have images for ldpi, mdpi, hdpi and x-hdpi.
Background image looks great, but all widgets (TextView, ProgressBar, ImageButton, etc) aren't in the right position when I test it on Samsung Galaxy Tab.
I have designed this layout on Eclipse using 'Nexus One` as a model.
Here people are recommend me that use only one layout for every screen size and densitiy, but it doesn't work. I'm using dp units and fill_parent, etc. but it is different on Galaxy Tab.
Do I need a layout for x-large screen sizes?

Indeed, the advice you received was good: it's possible to have only one layout file, but as it was already suggested in comments, it's not good to hardcode dimensions, even if you use dp or dip, specially when you are targeting all the screen sizes and densities available.
Instead, you should replace those values with links to dimensions values.
For example, instead of android:layout_marginLeft="10dp", you'll have something like
android:layout_marginLeft="#dimen/textview_margin_left"
where textview_margin_left is defined in the dimens.xml, having different values in different folders;
probably in folder values: <dimen name="textview_margin_left">10dp</dimen>,
in folder values-large: <dimen name="textview_margin_left">20dp</dimen>,
while in values-xlarge: <dimen name="textview_margin_left">30dp</dimen>
But this is just an example, you have to test on all dimensions and resolutions and find the best values for your layout. In Eclipse, in Graphical Layout mode, you can easily get an idea about how your layout looks on various devices, just by clicking on Nexus One, and choosing another model from the list, and the layout will automatically update.
Also, you can move in dimens.xml all the text sizes, and that will be very useful for x-large devices.
Using only one RelativeLayout instead many imbricated LinearLayouts might also be a good idea, and using relative positioning for your objects, instead some of the hardcoded values.

The Problem is following you use in your layout, static values (100dp, 60dp). Now the problem is on a higher resolution this dp isn't the same.
That means you should create a layout for x-large screens. Also I wouldn't use those static values. Than your application will behave good on many diffrent screensizes!
Have a great Day
safari