Android应用底部导航栏（选项卡）实例

现在很多Android的应用都采用底部导航栏的功能，这样可以使得用户在使用过程中随意切换不同的页面，现在我采用TabHost组件来自定义一个底部的导航栏的功能。我们先看下该demo实例的框架图：其中各个类的作用以及资源文件就不详细解释了，还有资源图片（在该Demo中借用了其它应用程序的资源图片）也不提供了，大家可以自行更换自己需要的资源图片。直接上各个布局文件或各个类的代码：[1] res/layout目录下的 maintabs.xml 源码：[html]

<？xml version="1.0" encoding="UTF-8"？>
<TabHost android:id="@android:id/tabhost" android:layout_width="fill_parent" android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<LinearLayout android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">
<FrameLayout android:id="@android:id/tabcontent" android:layout_width="fill_parent" android:layout_height="0.0dip" android:layout_weight="1.0" />
<TabWidget android:id="@android:id/tabs" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_weight="0.0" />
<RadioGroup
android:gravity="center_vertical" android:layout_gravity="bottom" android:orientation="horizontal" android:id="@id/main_radio" android:background="@drawable/maintab_toolbar_bg"
android:layout_width="fill_parent" android:layout_height="wrap_content">
<RadioButton android:id="@id/radio_button0" android:layout_marginTop="2.0dip" android:text="@string/main_home" android:drawableTop="@drawable/icon_1_n" style="@style/main_tab_bottom" />
<RadioButton android:id="@id/radio_button1" android:layout_marginTop="2.0dip" android:text="@string/main_news" android:drawableTop="@drawable/icon_2_n" style="@style/main_tab_bottom" />
<RadioButton android:id="@id/radio_button2" android:layout_marginTop="2.0dip" android:text="@string/main_manage_date" android:drawableTop="@drawable/icon_3_n" style="@style/main_tab_bottom" />
<RadioButton android:id="@id/radio_button3" android:layout_marginTop="2.0dip" android:text="@string/main_friends" android:drawableTop="@drawable/icon_4_n" style="@style/main_tab_bottom" />
<RadioButton android:id="@id/radio_button4" android:layout_marginTop="2.0dip" android:text="@string/more" android:drawableTop="@drawable/icon_5_n" style="@style/main_tab_bottom" />
</RadioGroup>
</LinearLayout>
</TabHost>

[2] res/drawable 下的 home_btn_bg.xml 源码：[html]

<？xml version="1.0" encoding="UTF-8"？>
<selector
xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true" android:state_enabled="true" android:state_pressed="false" android:drawable="@drawable/home_btn_bg_s" />
<item android:state_enabled="true" android:state_pressed="true" android:drawable="@drawable/home_btn_bg_s" />
<item android:state_enabled="true" android:state_checked="true" android:drawable="@drawable/home_btn_bg_d" />
<item android:drawable="@drawable/transparent" />
</selector>

[3] res/values 下的源码：dimens.xml源码[html]

<？xml version="1.0" encoding="utf-8"？>
<resources>
<dimen name="bottom_tab_font_size">10.0sp</dimen>
<dimen name="bottom_tab_padding_up">5.0dip</dimen>
<dimen name="bottom_tab_padding_drawable">2.0dip</dimen>
<dimen name="switch_logo_bottom_padding">30.0sp</dimen>
<dimen name="widget_height">100.0dip</dimen>
<dimen name="sta_height">48.0dip</dimen>
<dimen name="large_padding_length">20.0dip</dimen>
<dimen name="widget_write_margin_top">19.0dip</dimen>
<dimen name="widget_write_margin_left">10.0dip</dimen>
<dimen name="widget_content_margin_top">20.0dip</dimen>
<dimen name="widget_content_margin_left">10.0dip</dimen>
<dimen name="widget_logo_size">35.0dip</dimen>
<dimen name="title_height">74.0dip</dimen>
<dimen name="new_blog_size">70.0dip</dimen>
<dimen name="emotion_item_view_height">13.299988dip</dimen>
<dimen name="splash_test_top_margin_top">20.0dip</dimen>
<dimen name="splash_test_center_margin_right">0.0dip</dimen>
<dimen name="title_text_size">20.0sp</dimen>
<dimen name="normal_padding_length">10.0dip</dimen>
<dimen name="no_result_padding_length">50.0dip</dimen>
</resources>