Android自定义属性：format解析

冷不防 2022-06-05 02:52 660阅读 0赞

在values文件下有一个文件就是attrs.xml,这是R.attr和R.styleable类的定义文件。attrs.xml中定义了每个view的可用的属性，例如使用android:textAppearance就是在attrs.xml中定义了<attr name=”textAppearance” format=”reference” />，那麽这里点format=”reference”使什么意思呢。  
**1、reference :参考某一资源ID**  
(1)属性定义：

<declare-styleable name="名称">
      <attr name = "background" format="reference" />
    </declare-styleable>

(2)属性使用：

**2、color：颜色值**  
(1)属性定义：

<declare-styleable name="名称">
      <attr name = "textColor" format="color" />
    </declare-styleable>

(2)属性使用：

**3、boolean：布尔值**  
(1)属性定义：

<declare-styleable name="名称">
      <attr name = "focusable" format="boolean" />
    </declare-styleable>

(2)属性使用：

**4、dimension：尺寸值**  
(1)属性定义：

<declare-styleable name="名称">
      <attr name = "layout_width" format="dimension" />
    </declare-styleable>

(2)属性使用：

**5、float：浮点值**  
(1)属性定义：

<declare-styleable name="AlphaAnimation">
      <attr name = "fromAlpha" format="float" />
      <attr name = "toAlpha" format="float"/>
    </declare-styleable>

(2)属性使用：

**6、integer：整形值**  
(1)属性定义：

<declare-styleable name="AnimatedRotateDrawable">
      <attr name = "visible"/>
      <attr name = "fromDuration  " format="integer"/>
      <attr name = "fromsCount  " format="integer"/>
      <attr name = "pivotX"/>
      <attr name = "pivotY"/>
      <attr name = "drawable"/>
    </declare-styleable>

(2)属性使用：

<animated-rotate
          xmlns:android = "http://schemas.android.com/apk/res/anddroid"
          android:drawable= "@drawable/图片ID"
          android:pivotX = "50%"
          android:pivotY = "50%"
          android:framesCount = "12"
          android:frameDuration= "100" />

**7、string：字符串**  
(1)属性定义：

<declare-styleable name = "MapView">
        <attr name = "apiKey" format = "string" />
    </declare-styleable>

(2)属性使用：

<com.google.android.maps.MapView
       android:layout_width = "fill_parent"
       android:layout_height = "fill_parent"
       android:apiKey = "0jOkQ80oD1JL9C6HAja99uGXCRiS2CGjKO_bc_g" />

**8、fraction：百分数**  
(1)属性定义：

<decare-styleable name="RotateDrawable">
    <attr name = "visible" />
    <attr name = "fromDegrees" format = "float" />
    <attr name = "toDegrees" format = "float" />
    <attr name = "pivotX" format = "fraction" />
    <attr name = "pivotY" format = "fraction" />
    <attr name = "drawable" />
    </decare-styleable>

(2)属性使用：

**9、enum：枚举值**  
(1)属性定义：

<declare-styleable name="名称">
        <attr name="orientation">
             <enum name="horizontal" value="0" />
             <enum name="vertical" value="1" />
        </attr>            
    </declare-styleable>

(2)属性使用：

**10、flag：位或运算**  
(1)属性定义：

<declare-styleable name="名称">
        <attr name="windowSoftInputMode">
             <flag name = "stateUnspecified" value = "0" />
             <flag name = "stateUnchanged" value = "1" />
             <flag name = "stateHidden" value = "2" />
             <flag name = "stateAlwaysHidden" value = "3" />
             <flag name = "stateVisible" value = "4" />
             <flag name = "stateAlwaysVisible" value = "5" />
             <flag name = "adjustUnspecified" value = "0x00" />
             <flag name = "adjustResize" value = "0x10" />
             <flag name = "adjustPan" value = "0x20" />
             <flag name = "adjustNothing" value = "0x30" />
        </attr>         
    </declare-styleable>

(2)属性使用：

## 注意： ##

属性定义时可以指定多种类型值。

(1)属性定义：

<declare-styleable name = "名称">
      <attr name = "background" format = "reference|color" />
    </declare-styleable>

(2)属性使用：