Android settings for the control shadow

Set up a shadow in Android is very simple, just two steps:

1. Eleavation set value (height)
2. Outline or add a background (i.e., the shape of the shadow)

Description:

View is through the size of the position x, y is determined, and now has the concept of the z-axis, and this zvalue is View的高度（elevation）, the 高度决定了阴影（shadow）的大小.

NOTE: z value of View consists of two parts, elevation and translationZ (Android properties which are newly introduced L).

• eleavation: Static member: Set the component "float" up height;
• translationZ: Is used for animation: the assembly is provided displaced in the Z direction (vertical screen direction).

Z（阴影大小） = elevation + translationZ

Use to define attributes in the layout:

android:elevation="10dp"
android:translationZ="10dp"

Using java code

View.setElevation(float); 
View.setTranslationZ(float);

for example:

TextView to set up android:backgroundand elevation(height determines the size of the shadow).

<TextView
    android:id="@+id/myview"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:layout_margin="20dp"
    android:elevation="10dp"
    android:translationZ="1dp"
    android:text="阴影效果"
    android:gravity="center"
    android:background="@drawable/myrect" />

Then define a xml (myrect.xml, the paper put rec / drawable directory) background outline profile (profile determines the default background shadow shape):

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
    <solid android:color="#ffffff" />
    <corners android:radius="7dp" />
</shape>

When a profile view of this background drawable, rounded shadows projected view. Providing a custom profile, you can override the default view of the shape of the shadow.

The effect is as follows: