Android 通过findViewById方式创建TabHost

使用TabHost可以通过继承TabHost的方式，也可以通过继承ActivityGroup的方式。

通过extends TabHost比较简单，这里就不介绍了，以下是介绍通过extends ActivityGroup的方式使用TabHost，也就是通过findViewById方式创建TabHost对象的方式，这种方式大家可能会遇到以下错误提示：

1、java.lang.IllegalStateException: Did you forget to call 'public void setup，原因是未使用setup()

2、Android Exception: Did you forget to call 'public void setup (LocalActivityManager activityGroup)，原因是也是未正确使用setup()

3、java.lang.IllegalStateException: Activities can't be added until the containing group has been created.，原因是未继承ActivityGroup，如果只是extends Activity是不行的，必须extends ActivityGroup

4、其它错误......

原因都是因为没有按正确的方法调用TabHost，附上代码：

1、AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="org.shuxiang.tabhostsample"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="7"
        android:targetSdkVersion="15" />

    <application android:label="@string/app_name">
        <activity
            android:name=".MainActivity"
            android:label="@string/title_activity_main" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <activity android:name="Tab1" android:launchMode="singleInstance" android:screenOrientation="user" android:configChanges="orientation|keyboardHidden">
            <intent-filter>
                <action android:name="org.shuxiang.tabhostsample.Tab1" />
            </intent-filter>
    	</activity>

    	<activity android:name="Tab2" android:launchMode="singleInstance" android:screenOrientation="user" android:configChanges="orientation|keyboardHidden">
            <intent-filter>
                <action android:name="org.shuxiang.tabhostsample.Tab2" />
            </intent-filter>
    	</activity>
    
    	<activity android:name="Tab3" android:launchMode="singleInstance" android:screenOrientation="user" android:configChanges="orientation|keyboardHidden">
            <intent-filter>
                <action android:name="org.shuxiang.tabhostsample.Tab3" />
            </intent-filter>
    	</activity>   
    </application>

</manifest>

layout下的布局文件：

2、tabhost.xml

<?xml version="1.0" encoding="utf-8"?>
<TabHost android:id="@android:id/tabhost" xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" android:layout_height="fill_parent">    
    <LinearLayout android:id="@+id/LinearLayout01" android:layout_height="fill_parent" android:layout_width="fill_parent" android:orientation="vertical">
    	<TabWidget android:id="@android:id/tabs" android:layout_height="wrap_content" android:layout_width="fill_parent" />
    	<FrameLayout android:id="@android:id/tabcontent" android:layout_width="fill_parent" android:layout_height="fill_parent" />
	</LinearLayout>
</TabHost>

3、tabhost1.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="horizontal">
   
    <TextView android:id="@+id/TextView01"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="第一个"
        android:padding="10px"/>
   
</LinearLayout>

4、tabhost2.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="horizontal">
   
    <TextView android:id="@+id/TextView02"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="第二个"
        android:padding="10px"/>
   
</LinearLayout>

5、tabhost3.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="horizontal">
   
    <TextView android:id="@+id/TextView02"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="第三个"
        android:padding="10px"/>
   
</LinearLayout>

value下的文件：

6、strings.xml

<resources>
    <string name="app_name">TabHostSample</string>
    <string name="hello_world">Hello world!</string>
    <string name="menu_settings">Settings</string>
    <string name="title_activity_main">MainActivity</string>
</resources>

类文件：

7、MainActivity.java

package org.shuxiang.tabhostsample;

import android.os.Bundle;
import android.app.ActivityGroup;
import android.content.Intent;
import android.widget.TabHost;

public class MainActivity extends ActivityGroup
{
	private String tabHost1 = "A";
	private String tabHost2 = "B";
	private String tabHost3 = "C";
	private TabHost tabHost;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tabhost);
        
        tabHost = (TabHost) findViewById(android.R.id.tabhost);

     	tabHost.setup(getLocalActivityManager());
        
        tabHost.setCurrentTab(0);
        tabHost.addTab(tabHost.newTabSpec(tabHost1)
        .setIndicator(tabHost1).
        setContent(new Intent(MainActivity.this, Tab1.class)));
        tabHost.addTab(tabHost.newTabSpec(tabHost2)
        .setIndicator(tabHost2)
        .setContent(new Intent(MainActivity.this, Tab2.class)));
        tabHost.addTab(tabHost.newTabSpec(tabHost3)
        .setIndicator(tabHost3)
        .setContent(new Intent(MainActivity.this, Tab3.class)));

    }


}

8、Tab1.java

package org.shuxiang.tabhostsample;

import android.app.Activity;
import android.os.Bundle;

public class Tab1 extends Activity
{
	@Override
    public void onCreate(Bundle savedInstanceState)
	{
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tabhost1);
	}
}

9、Tab2.java

package org.shuxiang.tabhostsample;

import android.app.Activity;
import android.os.Bundle;

public class Tab2 extends Activity
{
	@Override
    public void onCreate(Bundle savedInstanceState)
	{
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tabhost2);
	}
}

10、Tab3.java

package org.shuxiang.tabhostsample;

import android.app.Activity;
import android.os.Bundle;

public class Tab3 extends Activity
{
	@Override
    public void onCreate(Bundle savedInstanceState)
	{
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tabhost3);
	}
}

附上效果图：