自定义控件的自定义的属性attrs.xml下的declare-styleable中format详解

最近在摸索自定义控件,查找到一些自定义属性的一些资料,解决转载记载下来:看了此详解才方便理解!

我们在做项目的时候,由于android自带的属性不能满足需求,android提供了自定义属性的方法,其中的format是做什么用的?以及如何使用它?下面列出一些常用的。

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"

/>

配合示意图方便理解:(图片看不全请将图片下载保存本地查看)

  自定义控件的自定义的属性attrs.xml下的declare-styleable中format详解

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>

特别要注意:

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"

/>

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