Android学习路线（九）为Action Bar添加Style

这里先贴出原文，下次再来翻译；:p

原文地址：http://developer.android.com/training/basics/actionbar/styling.html

The action bar provides your users a familiar and predictable way to perform actions and navigate your app, but that doesn‘t mean it needs to look exactly the same as it does in other apps. If you want to style the action bar to better fit your product brand,
you can easily do so using Android‘s style and theme resources.

Android includes a few built-in activity themes that include "dark" or "light" action bar styles. You can also extend these themes to further customize the look for your action bar.

Note: If you are using the Support Library APIs for the action bar, then you must use (or override) theTheme.AppCompat family
of styles (rather than the Theme.Holo family,
available in API level 11 and higher). In doing so, each style property that you declare must be declared twice: once using the platform‘s style properties (the android: properties)
and once using the style properties included in the Support Library (theappcompat.R.attr properties—the
context for these properties is actually your app). See the examples below for details.

Use an Android Theme

Android includes two baseline activity themes that dictate the color for the action bar:

• Theme.Holo for
  a "dark" theme.
• Theme.Holo.Light for
  a "light" theme.

You can apply these themes to your entire app or to individual activities by declaring them in your manifest file with the android:theme attribute for the<application> element
or individual <activity>elements.

For example:

<application android:theme="@android:style/Theme.Holo.Light" ... />

You can also use a dark action bar while the rest of the activity uses the light color scheme by declaring the Theme.Holo.Light.DarkActionBar theme.

When using the Support Library, you must instead use the Theme.AppCompat themes:

• Theme.AppCompat for
  the "dark" theme.
• Theme.AppCompat.Light for
  the "light" theme.
• Theme.AppCompat.Light.DarkActionBar for
  the light theme with a dark action bar.

Be sure that you use action bar icons that properly contrast with the color of your action bar. To help you, theAction
Bar Icon Pack includes standard action icons for use with both the Holo light and Holo dark action bar.

Customize the Background

To change the action bar background, create a custom theme for your activity that overrides theactionBarStyle property.
This property points to another style in which you can override the backgroundproperty
to specify a drawable resource for the action bar background.

If your app uses navigation tabs or the split
action bar, then you can also specify the background for these bars using the backgroundStacked and backgroundSplit properties,
respectively.

Caution: It‘s important that you declare an appropriate parent theme from which your custom theme and style inherit their styles. Without a parent style, your action bar will be without many style properties unless you explicitly declare them
yourself.

For Android 3.0 and higher only

When supporting Android 3.0 and higher only, you can define the action bar‘s background like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@android:style/Theme.Holo.Light.DarkActionBar">
        <item name="android:actionBarStyle">@style/MyActionBar</item>
    </style>

    <!-- ActionBar styles -->
    <style name="MyActionBar"
           parent="@android:style/Widget.Holo.Light.ActionBar.Solid.Inverse">
        <item name="android:background">@drawable/actionbar_background</item>
    </style>
</resources>

Then apply your theme to your entire app or individual activities:

<application android:theme="@style/CustomActionBarTheme" ... />

For Android 2.1 and higher

When using the Support Library, the same theme as above must instead look like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@style/Theme.AppCompat.Light.DarkActionBar">
        <item name="android:actionBarStyle">@style/MyActionBar</item>

        <!-- Support library compatibility -->
        <item name="actionBarStyle">@style/MyActionBar</item>
    </style>

    <!-- ActionBar styles -->
    <style name="MyActionBar"
           parent="@style/Widget.AppCompat.Light.ActionBar.Solid.Inverse">
        <item name="android:background">@drawable/actionbar_background</item>

        <!-- Support library compatibility -->
        <item name="background">@drawable/actionbar_background</item>
    </style>
</resources>

Then apply your theme to your entire app or individual activities:

<application android:theme="@style/CustomActionBarTheme" ... />

Customize the Text Color

• Action bar title: Create a custom style that specifies the textColor property and specify that style for thetitleTextStyle property
  in your custom actionBarStyle.

  Note: The custom style applied to titleTextStyle should
  useTextAppearance.Holo.Widget.ActionBar.Title as
  the parent style.

• Action bar tabs: Override actionBarTabTextStyle in
  your activity theme.
• Action buttons: Override actionMenuTextColor in
  your activity theme.

For Android 3.0 and higher only

When supporting Android 3.0 and higher only, your style XML file might look like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@style/Theme.Holo">
        <item name="android:actionBarStyle">@style/MyActionBar</item>
        <item name="android:actionBarTabTextStyle">@style/MyActionBarTabText</item>
        <item name="android:actionMenuTextColor">@color/actionbar_text</item>
    </style>

    <!-- ActionBar styles -->
    <style name="MyActionBar"
           parent="@style/Widget.Holo.ActionBar">
        <item name="android:titleTextStyle">@style/MyActionBarTitleText</item>
    </style>

    <!-- ActionBar title text -->
    <style name="MyActionBarTitleText"
           parent="@style/TextAppearance.Holo.Widget.ActionBar.Title">
        <item name="android:textColor">@color/actionbar_text</item>
    </style>

    <!-- ActionBar tabs text styles -->
    <style name="MyActionBarTabText"
           parent="@style/Widget.Holo.ActionBar.TabText">
        <item name="android:textColor">@color/actionbar_text</item>
    </style>
</resources>

For Android 2.1 and higher

When using the Support Library, your style XML file might look like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@style/Theme.AppCompat">
        <item name="android:actionBarStyle">@style/MyActionBar</item>
        <item name="android:actionBarTabTextStyle">@style/MyActionBarTabText</item>
        <item name="android:actionMenuTextColor">@color/actionbar_text</item>

        <!-- Support library compatibility -->
        <item name="actionBarStyle">@style/MyActionBar</item>
        <item name="actionBarTabTextStyle">@style/MyActionBarTabText</item>
        <item name="actionMenuTextColor">@color/actionbar_text</item>
    </style>

    <!-- ActionBar styles -->
    <style name="MyActionBar"
           parent="@style/Widget.AppCompat.ActionBar">
        <item name="android:titleTextStyle">@style/MyActionBarTitleText</item>

        <!-- Support library compatibility -->
        <item name="titleTextStyle">@style/MyActionBarTitleText</item>
    </style>

    <!-- ActionBar title text -->
    <style name="MyActionBarTitleText"
           parent="@style/TextAppearance.AppCompat.Widget.ActionBar.Title">
        <item name="android:textColor">@color/actionbar_text</item>
        <!-- The textColor property is backward compatible with the Support Library -->
    </style>

    <!-- ActionBar tabs text -->
    <style name="MyActionBarTabText"
           parent="@style/Widget.AppCompat.ActionBar.TabText">
        <item name="android:textColor">@color/actionbar_text</item>
        <!-- The textColor property is backward compatible with the Support Library -->
    </style>
</resources>

Customize the Tab Indicator

To change the indicator used for the navigation tabs, create an activity theme that overrides theactionBarTabStyle property.
This property points to another style resource in which you override thebackground property
that should specify a state-list drawable.

Note: A state-list drawable is important so that the tab currently selected indicates its state with a background different than the other tabs. For more information about how to create a drawable resource that handles multiple button states,
read the State List documentation.

For example, here‘s a state-list drawable that declares a specific background image for several different states of an action bar tab:

res/drawable/actionbar_tab_indicator.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

<!-- STATES WHEN BUTTON IS NOT PRESSED -->

    <!-- Non focused states -->
    <item android:state_focused="false" android:state_selected="false"
          android:state_pressed="false"
          android:drawable="@drawable/tab_unselected" />
    <item android:state_focused="false" android:state_selected="true"
          android:state_pressed="false"
          android:drawable="@drawable/tab_selected" />

    <!-- Focused states (such as when focused with a d-pad or mouse hover) -->
    <item android:state_focused="true" android:state_selected="false"
          android:state_pressed="false"
          android:drawable="@drawable/tab_unselected_focused" />
    <item android:state_focused="true" android:state_selected="true"
          android:state_pressed="false"
          android:drawable="@drawable/tab_selected_focused" />

<!-- STATES WHEN BUTTON IS PRESSED -->

    <!-- Non focused states -->
    <item android:state_focused="false" android:state_selected="false"
          android:state_pressed="true"
          android:drawable="@drawable/tab_unselected_pressed" />
    <item android:state_focused="false" android:state_selected="true"
        android:state_pressed="true"
        android:drawable="@drawable/tab_selected_pressed" />

    <!-- Focused states (such as when focused with a d-pad or mouse hover) -->
    <item android:state_focused="true" android:state_selected="false"
          android:state_pressed="true"
          android:drawable="@drawable/tab_unselected_pressed" />
    <item android:state_focused="true" android:state_selected="true"
          android:state_pressed="true"
          android:drawable="@drawable/tab_selected_pressed" />
</selector>

For Android 3.0 and higher only

When supporting Android 3.0 and higher only, your style XML file might look like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@style/Theme.Holo">
        <item name="android:actionBarTabStyle">@style/MyActionBarTabs</item>
    </style>

    <!-- ActionBar tabs styles -->
    <style name="MyActionBarTabs"
           parent="@style/Widget.Holo.ActionBar.TabView">
        <!-- tab indicator -->
        <item name="android:background">@drawable/actionbar_tab_indicator</item>
    </style>
</resources>

For Android 2.1 and higher

When using the Support Library, your style XML file might look like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme"
           parent="@style/Theme.AppCompat">
        <item name="android:actionBarTabStyle">@style/MyActionBarTabs</item>

        <!-- Support library compatibility -->
        <item name="actionBarTabStyle">@style/MyActionBarTabs</item>
    </style>

    <!-- ActionBar tabs styles -->
    <style name="MyActionBarTabs"
           parent="@style/Widget.AppCompat.ActionBar.TabView">
        <!-- tab indicator -->
        <item name="android:background">@drawable/actionbar_tab_indicator</item>

        <!-- Support library compatibility -->
        <item name="background">@drawable/actionbar_tab_indicator</item>
    </style>
</resources>

More resources

• See more style properties for the action bar are listed in the Action Bar guide.
• Learn more about how themes work in the Styles and Themes guide.
• For even more complete styling for the action bar, try the Android
  Action Bar Style Generator.

Android学习路线（九）为Action Bar添加Style