为 ImageButton 的 drawable 添加阴影

Question

I have a image button which is designed like this

 <ImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/plusOneButton"
            android:layout_marginBottom="5dp"
            android:src="@drawable/thinking"
            android:layout_marginLeft="8dp"
            android:layout_marginRight="8dp"
            android:background="@drawable/button_border"
            />

The button_border xml looks like this.

  <?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    >
    <stroke
        android:width="30dp"
        android:color="#ff000000" />
    <padding
        android:left="1dp"
        android:top="1dp"
        android:right="1dp"
        android:bottom="1dp" />

</shape>

There fore the image is enclosed by a box, It doesn't look like a pressable button. How do i add shadows to it to make it look like a button? Kindly help, I am new to android. I don't want to add ripple as the minimum api level in my app is 14.

Answer 1

You can use the Layer-List which give you the ability to add two or more shapes in order to achieve the shadow then you need to create a selector drawable to set what are the drawable to use in each state like focus , pressed ... etc these links will help you check them :

layer-list

http://nick.perfectedz.com/android-layerlist-tip/

Selector

http://www.compiletimeerror.com/2014/03/android-button-selector-tutorial-with.html

i hope this will help you :)