Android自定义属性，format详解
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：
<ImageView android:layout_width = "42dip" android:layout_height = "42dip" android:background = "@drawable/图片ID" />
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：
<TextView android:layout_width = "42dip" android:layout_height = "42dip" android:textColor = "#00FF00" />
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：
<Button android:layout_width = "42dip" android:layout_height = "42dip" android:focusable = "true" />
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：
<Button android:layout_width = "42dip" android:layout_height = "42dip" />
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：
<alpha android:fromAlpha = "1.0" android:toAlpha = "0.7" />
6. integer：整型值。
（1）属性定义：
<declare-styleable name = "AnimatedRotateDrawable"> <attr name = "visible" /> <attr name = "frameDuration" format="integer" /> <attr name = "framesCount" 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/android" 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：
<declare-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" /> </declare-styleable>
（2）属性使用：
<rotate xmlns:android = "http://schemas.android.com/apk/res/android" android:interpolator = "@anim/动画ID" android:fromDegrees = "0" android:toDegrees = "360" android:pivotX = "200%" android:pivotY = "300%" android:duration = "5000" android:repeatMode = "restart" android:repeatCount = "infinite" />
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：
<LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:orientation = "vertical" android:layout_width = "fill_parent" android:layout_height = "fill_parent" > </LinearLayout>
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：
<activity android:name = ".StyleAndThemeActivity" android:label = "@string/app_name" android:windowSoftInputMode = "stateUnspecified | stateUnchanged | stateHidden"> <intent-filter> <action android:name = "android.intent.action.MAIN" /> <category android:name = "android.intent.category.LAUNCHER" /> </intent-filter> </activity>
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：
<ImageView android:layout_width = "42dip" android:layout_height = "42dip" android:background = "@drawable/图片ID|#00FF00" />
