###Introduction Kite is an Simple Android View Layout Extension Framework. Give you powerful view layouting via json parameter; which makes layouting view simple and easily. all you need is two step

1, add json parameters with math expression to android:contentDescription or android:tag attribute.

<View
    android:id="@+id/view"  
    ...
    android:contentDescription="{'height':'screen_height*3', 'width':'screen_width - 20dp'}"/>

or

<View
    android:id="@+id/view"   
    ...
    android:tag="{'height':'screen_height*3', 'width':'screen_width - 20dp'}"/>

2, call Kite.layout(View v) method, layout parameters will take effect.

 Kite.layout(findViewById(R.id.view));

Kite Layout Process

###Quick Start

####1, make view's width = height*0.5

add android:contentDescription='{"width":"height*0.5"}' to your TextView

 <TextView
    android:id="@+id/textview"  
    ...
    android:contentDescription='{"width":"height*0.5"}'/>

add Kite.layout(View v) in your code to make the layout parameters take effect

Kite.layout(findViewById(R.id.textview)); 

####2, make view's height = 0.5*width + screen_height/3.0

add android:contentDescription='{"height":"0.5*width + screen_height/3.0"}' to your ViewPager

 <ViewPager
    android:id="@+id/viewpager"  
    ...
    android:tag='{"height":"0.5*width  + screen_height/3.0"}'/>

add Kite.layout(View v) in your code to make the layout parameters take effect

Kite.layout(findViewById(R.id.viewpager));  

####3, layout view and it's subviews via Kite

with Kite, you can make radio image and square image easily.

<LinearLayout 
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
     android:id="@+id/image_container" 
     >
    <!-- radio image, height = width*0.5 -->
    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="#000fff" 
        android:contentDescription="{'height':'width*0.5'}"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
       <!-- square image, height = width -->
       <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:background="#888000" 
        android:contentDescription="{'height':'width'}"/> 
        <!-- square image, height = width -->
       <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:background="#888fff" 
        android:contentDescription="{'height':'width'}"/> 
    </LinearLayout>
</LinearLayout>    

Kite will transverse v, and layout all its subviews, all you need is one line code:

Kite.layout(findViewById(R.id.image_container));

####4, variable you can use in math expression

height ----> view's height in pixel
width  ----> view's width in pixel
parent_height ---> view's parent height in pixel
parent_width  ---> view's parent width in pixel
screen_height ---> device screen height in pixel
screen_width  ---> device screen width in pixel
density       ---> pixel per one dp
dp            ---> dp

tips: unit of math expression value is in pixel

you can write any valid math expression you like; fox example:

android:contentDescription="{'height':'screen_height*0.8', 'width':'screen_width*0.4 + 10dp'}"        
android:tag="{'height':'height*0.3', 'width':'screen_width/2.0 - 40dp'}"       
android:tag="{'height':'height*0.4 + width/2.0', 'width':'parent_height/3.0  + screen_height/2.0'}"  

####5, download Kite

Kite use Exp4j as default math expression evaluator. When you use Kite, you need download Exp4j.

Kite-1.0.0.jar

Exp4j-0.3.9.jar

Maven

<dependency>
   <groupId>com.efurture.kite</groupId>
   <artifactId>kite</artifactId>
   <version>1.0.0</version>
</dependency>
<dependency>
		<groupId>de.congrace</groupId>
		<artifactId>exp4j</artifactId>
		<version>0.3.9</version>
</dependency>

Kite also support mvel2 as math expression evaluator. just call

Kite.setDefaultEvaluator(new MVEL2Evaluator());

if this cann't satisfy you, you can write your own math expression evaluator.

1, create subclass of Evaluator

public class CustomEvaluator extends Evaluator {
	
	@Override
	protected int evalute(String expression, Map<String, Object> paramsMap) {
	    //do some to get expression value
		return value;
	}
	
}

2, register your CustomEvaluator to Kite as default evaluator.

 Kite.setDefaultEvaluator(new CustomEvaluator());

Kite Api: http://gubaojian.github.io/Kite/apidocs/

Exp4j http://www.objecthunter.net/exp4j/

MVEL2 http://mvel.codehaus.org/

###Bug Reports

you can give suggestions and bug reports via github or email to me.

Email: gubaojian@163.com

###License

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.