android - Responsive activity -

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i'm learning develop android application 2 months now. have lot of question according layouts on android.

i read this article , others on official documentation website (can't find link). understand in order screen size of elements matches resolution of phone, need use density-independent pixel (dp) element.

let's imagine order layout according documentation : 

res/layout/main_activity.xml           # handsets (smaller 600dp available width) res/layout-sw600dp/main_activity.xml   # 7” tablets (600dp wide , bigger) res/layout-sw720dp/main_activity.xml   # 10” tablets (720dp wide , bigger)

just talk handset configuration. read in documentation the density-independent pixel equivalent 1 physical pixel on 160 dpi screen, baseline density assumed system "medium" density screen. maximum height , width can use in res/layout/main_activity.xml in dp ? if have same layout 4, 5, 6" phones, how possible me set image @ 50% of screen length using dp example ?

i must forget me understand how works..

you can use percentrelativelayout percent support library, see example :

<android.support.percent.percentrelativelayout 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/top_left"     android:layout_width="0dp"     android:layout_height="0dp"     android:layout_alignparenttop="true"     android:background="#ff44aacc"     app:layout_heightpercent="20%"     app:layout_widthpercent="70%" />  <view     android:id="@+id/top_right"     android:layout_width="0dp"     android:layout_height="0dp"     android:layout_alignparenttop="true"     android:layout_torightof="@+id/top_left"     android:background="#ffe40000"     app:layout_heightpercent="20%"     app:layout_widthpercent="30%" />  <view     android:id="@+id/bottom"     android:layout_width="match_parent"     android:layout_height="0dp"     android:layout_below="@+id/top_left"     android:background="#ff00ff22"     app:layout_heightpercent="80%" /> </android.support.percent.percentrelativelayout>

the result :

enter image description here

don't froget add compile 'com.android.support:percent:23.3.0' in build.gradle

check tutorial more informations how constructing view layouts.


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