【Android】TabHost与RadioGroup结合完成的菜单

效果图: 
 

首先看布局文件： 

 "1.0" encoding="UTF-8"?>
 "@android:id/tabhost" android:layout_width="fill_parent" android:layout_height="fill_parent"
   xmlns:android="http://schemas.android.com/apk/res/android">

         android:orientation="vertical"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent">

             android:id="@android:id/tabcontent"
             android:layout_width="fill_parent"
             android:layout_height="0.0dip"
             android:layout_weight="1.0" />

             android:id="@android:id/tabs"
             android:visibility="gone"
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:layout_weight="0.0" />

             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">

                 android:id="@+id/radio_button0"
                 android:tag="radio_button0"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/alarm"
                 android:drawableTop="@drawable/icon_1"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button1"
                 android:tag="radio_button1"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/message"
                 android:drawableTop="@drawable/icon_2"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button2"
                 android:tag="radio_button2"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/photo"
                 android:drawableTop="@drawable/icon_3"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button3"
                 android:tag="radio_button3"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/music"
                 android:drawableTop="@drawable/icon_4"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button4"
                 android:tag="radio_button4"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/setting"
                 android:drawableTop="@drawable/icon_5"
                 style="@style/main_tab_bottom" />

 "1.0" encoding="UTF-8"?>
 "@android:id/tabhost" android:layout_width="fill_parent" android:layout_height="fill_parent"
   xmlns:android="http://schemas.android.com/apk/res/android">

         android:orientation="vertical"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent">

             android:id="@android:id/tabcontent"
             android:layout_width="fill_parent"
             android:layout_height="0.0dip"
             android:layout_weight="1.0" />

             android:id="@android:id/tabs"
             android:visibility="gone"
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:layout_weight="0.0" />

             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">

                 android:id="@+id/radio_button0"
                 android:tag="radio_button0"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/alarm"
                 android:drawableTop="@drawable/icon_1"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button1"
                 android:tag="radio_button1"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/message"
                 android:drawableTop="@drawable/icon_2"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button2"
                 android:tag="radio_button2"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/photo"
                 android:drawableTop="@drawable/icon_3"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button3"
                 android:tag="radio_button3"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/music"
                 android:drawableTop="@drawable/icon_4"
                 style="@style/main_tab_bottom" />

                 android:id="@+id/radio_button4"
                 android:tag="radio_button4"
                 android:layout_marginTop="2.0dip"
                 android:text="@string/setting"
                 android:drawableTop="@drawable/icon_5"
                 style="@style/main_tab_bottom" />

需要注意的是，如果用TabHost这个控件，其中有几个ID是必须这么写的，android:id="@android:id/tabhost   ；android:id="@android:id/tabcontent" ；android:id="@android:id/tabs" ；之所以要这么写是因为在TabHost这个类中。需要实例化上述这个ID的控件。看源码： 

在TabActivity中有么个方法： 

 @Override
 public void onContentChanged() {
     super.onContentChanged();
     mTabHost = (TabHost) findViewById(com.android.internal.R.id.tabhost);

     if (mTabHost == null) {
         throw new RuntimeException(
                 "Your content must have a TabHost whose id attribute is " +
                 "'android.R.id.tabhost'");
     }
     mTabHost.setup(getLocalActivityManager());
 }

 private void ensureTabHost() {
     if (mTabHost == null) {
         this.setContentView(com.android.internal.R.layout.tab_content);
     }
 }

 @Override
 public void onContentChanged() {
     super.onContentChanged();
     mTabHost = (TabHost) findViewById(com.android.internal.R.id.tabhost);

     if (mTabHost == null) {
         throw new RuntimeException(
                 "Your content must have a TabHost whose id attribute is " +
                 "'android.R.id.tabhost'");
     }
     mTabHost.setup(getLocalActivityManager());
 }

 private void ensureTabHost() {
     if (mTabHost == null) {
         this.setContentView(com.android.internal.R.layout.tab_content);
     }
 }

当内容发生改变时它会调用这个方法，来更新列表或者其他视图，而这个方法中需要实例化TabHost，所以必须通过ID为tabhost实例化。 

再看看TabHost这个类中， 

 public void setup() {
     mTabWidget = (TabWidget) findViewById(com.android.internal.R.id.tabs);
     if (mTabWidget == null) {
         throw new RuntimeException(
                 "Your TabHost must have a TabWidget whose id attribute is 'android.R.id.tabs'");
     }

     // KeyListener to attach to all tabs. Detects non-navigation keys
     // and relays them to the tab content.
     mTabKeyListener = new OnKeyListener() {
         public boolean onKey(View v, int keyCode, KeyEvent event) {
             switch (keyCode) {
                 case KeyEvent.KEYCODE_DPAD_CENTER:
                 case KeyEvent.KEYCODE_DPAD_LEFT:
                 case KeyEvent.KEYCODE_DPAD_RIGHT:
                 case KeyEvent.KEYCODE_DPAD_UP:
                 case KeyEvent.KEYCODE_DPAD_DOWN:
                 case KeyEvent.KEYCODE_ENTER:
                     return false;

             }
             mTabContent.requestFocus(View.FOCUS_FORWARD);
             return mTabContent.dispatchKeyEvent(event);
         }

     };

     mTabWidget.setTabSelectionListener(new TabWidget.OnTabSelectionChanged() {
         public void onTabSelectionChanged(int tabIndex, boolean clicked) {
             setCurrentTab(tabIndex);
             if (clicked) {
                 mTabContent.requestFocus(View.FOCUS_FORWARD);
             }
         }
     });

     mTabContent = (FrameLayout) findViewById(com.android.internal.R.id.tabcontent);
     if (mTabContent == null) {
         throw new RuntimeException(
                 "Your TabHost must have a FrameLayout whose id attribute is "
                         + "'android.R.id.tabcontent'");
     }
 }

 public void setup() {
     mTabWidget = (TabWidget) findViewById(com.android.internal.R.id.tabs);
     if (mTabWidget == null) {
         throw new RuntimeException(
                 "Your TabHost must have a TabWidget whose id attribute is 'android.R.id.tabs'");
     }

     // KeyListener to attach to all tabs. Detects non-navigation keys
     // and relays them to the tab content.
     mTabKeyListener = new OnKeyListener() {
         public boolean onKey(View v, int keyCode, KeyEvent event) {
             switch (keyCode) {
                 case KeyEvent.KEYCODE_DPAD_CENTER:
                 case KeyEvent.KEYCODE_DPAD_LEFT:
                 case KeyEvent.KEYCODE_DPAD_RIGHT:
                 case KeyEvent.KEYCODE_DPAD_UP:
                 case KeyEvent.KEYCODE_DPAD_DOWN:
                 case KeyEvent.KEYCODE_ENTER:
                     return false;

             }
             mTabContent.requestFocus(View.FOCUS_FORWARD);
             return mTabContent.dispatchKeyEvent(event);
         }

     };

     mTabWidget.setTabSelectionListener(new TabWidget.OnTabSelectionChanged() {
         public void onTabSelectionChanged(int tabIndex, boolean clicked) {
             setCurrentTab(tabIndex);
             if (clicked) {
                 mTabContent.requestFocus(View.FOCUS_FORWARD);
             }
         }
     });

     mTabContent = (FrameLayout) findViewById(com.android.internal.R.id.tabcontent);
     if (mTabContent == null) {
         throw new RuntimeException(
                 "Your TabHost must have a FrameLayout whose id attribute is "
                         + "'android.R.id.tabcontent'");
     }
 }

这个方法，是在增加选项卡之前由系统调用。在这个方法中需要通过tabs 这个ID实例化一个TabWidget，通过tabcontent这个ID实例化一个FrameLayout，用来放置选项卡内容。所以这两个ID也是固定的。 

在上述布局文件中隐藏了系统默认的Widget，取而代之的是带有图片的Button。 

看一下主要代码： 

 package com.iteye.androidtoast;

 import android.app.TabActivity;
 import android.content.Intent;
 import android.os.Bundle;
 import android.widget.RadioGroup;
 import android.widget.RadioGroup.OnCheckedChangeListener;
 import android.widget.TabHost;

 public class MainActivity extends TabActivity implements OnCheckedChangeListener{
     /** Called when the activity is first created. */
     private TabHost mHost;
     private RadioGroup radioderGroup;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.maintabs);
         //实例化TabHost
         mHost=this.getTabHost();

         //添加选项卡
         mHost.addTab(mHost.newTabSpec("ONE").setIndicator("ONE")
                     .setContent(new Intent(this,OneActivity.class)));
         mHost.addTab(mHost.newTabSpec("TWO").setIndicator("TWO")
                 .setContent(new Intent(this,TwoActivity.class)));
         mHost.addTab(mHost.newTabSpec("THREE").setIndicator("THREE")
                 .setContent(new Intent(this,ThreeActivity.class)));
         mHost.addTab(mHost.newTabSpec("FOUR").setIndicator("FOUR")
                 .setContent(new Intent(this,FourActivity.class)));
         mHost.addTab(mHost.newTabSpec("FIVE").setIndicator("FIVE")
                 .setContent(new Intent(this,FiveActivity.class)));

         radioderGroup = (RadioGroup) findViewById(R.id.main_radio);
         radioderGroup.setOnCheckedChangeListener(this);
     }
     @Override
     public void onCheckedChanged(RadioGroup group, int checkedId) {
         switch(checkedId){
         case R.id.radio_button0:
             mHost.setCurrentTabByTag("ONE");
             break;
         case R.id.radio_button1:
             mHost.setCurrentTabByTag("TWO");
             break;
         case R.id.radio_button2:
             mHost.setCurrentTabByTag("THREE");
             break;
         case R.id.radio_button3:
             mHost.setCurrentTabByTag("FOUR");
             break;
         case R.id.radio_button4:
             mHost.setCurrentTabByTag("FIVE");
             break;
         }
     }
 }

 package com.iteye.androidtoast;

 import android.app.TabActivity;
 import android.content.Intent;
 import android.os.Bundle;
 import android.widget.RadioGroup;
 import android.widget.RadioGroup.OnCheckedChangeListener;
 import android.widget.TabHost;

 public class MainActivity extends TabActivity implements OnCheckedChangeListener{
     /** Called when the activity is first created. */
     private TabHost mHost;
     private RadioGroup radioderGroup;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.maintabs);
         //实例化TabHost
         mHost=this.getTabHost();

         //添加选项卡
         mHost.addTab(mHost.newTabSpec("ONE").setIndicator("ONE")
                     .setContent(new Intent(this,OneActivity.class)));
         mHost.addTab(mHost.newTabSpec("TWO").setIndicator("TWO")
                 .setContent(new Intent(this,TwoActivity.class)));
         mHost.addTab(mHost.newTabSpec("THREE").setIndicator("THREE")
                 .setContent(new Intent(this,ThreeActivity.class)));
         mHost.addTab(mHost.newTabSpec("FOUR").setIndicator("FOUR")
                 .setContent(new Intent(this,FourActivity.class)));
         mHost.addTab(mHost.newTabSpec("FIVE").setIndicator("FIVE")
                 .setContent(new Intent(this,FiveActivity.class)));

         radioderGroup = (RadioGroup) findViewById(R.id.main_radio);
         radioderGroup.setOnCheckedChangeListener(this);
     }
     @Override
     public void onCheckedChanged(RadioGroup group, int checkedId) {
         switch(checkedId){
         case R.id.radio_button0:
             mHost.setCurrentTabByTag("ONE");
             break;
         case R.id.radio_button1:
             mHost.setCurrentTabByTag("TWO");
             break;
         case R.id.radio_button2:
             mHost.setCurrentTabByTag("THREE");
             break;
         case R.id.radio_button3:
             mHost.setCurrentTabByTag("FOUR");
             break;
         case R.id.radio_button4:
             mHost.setCurrentTabByTag("FIVE");
             break;
         }
     }
 }

转载自：http://www.iteye.com/topic/1116261