一个TabHost对象包含两个子元素对象:
一个对象是tab标签集合(TabWidget),用户点击它们来选择一个特定的标签;
另一个是FrameLayout对象,展示当前页的内容
子元素通常是通过容器对象来控制,而不是直接设置子元素的值。
下面结合ApiDemos中的例子来说明TabHost的用法。
1、使用的TabActivity
package com.meng.hellotab; import android.os.Bundle; import android.view.LayoutInflater; import android.widget.TabHost; import android.app.TabActivity; @SuppressWarnings("deprecation") public class HelloTabActivity extends TabActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // 得到TabActivity中的TabHost对象 TabHost tabHost = getTabHost(); // 内容:采用布局文件中的布局 LayoutInflater.from(this).inflate(R.layout.activity_hello_tab, tabHost.getTabContentView(), true); // 加上标签 // 参数设置:新增的TabSpec的标签,标签中显示的字样 // setContent设置内容对应的View资源标号 tabHost.addTab(tabHost.newTabSpec("tab1") .setIndicator("tab1 indicator").setContent(R.id.view1)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab2") .setContent(R.id.view2)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab3") .setContent(R.id.view3)); } }
布局文件1 <?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" > <TextView android:id="@+id/view1" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/blue" android:text="@string/tab1" /> <TextView android:id="@+id/view2" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/red" android:text="@string/tab2" /> <TextView android:id="@+id/view3" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/green" android:text="@string/tab3" /> </FrameLayout>
colors.xml 颜色文件: <?xml version="1.0" encoding="utf-8"?> <resources> <drawable name="red">#7f00</drawable> <drawable name="blue">#770000ff</drawable> <drawable name="green">#7700ff00</drawable> <drawable name="yellow">#77ffff00</drawable> <drawable name="screen_background_black">#ff000000</drawable> <drawable name="translucent_background">#e0000000</drawable> <drawable name="transparent_background">#00000000</drawable> <color name="solid_red">#f00</color> <color name="solid_blue">#0000ff</color> <color name="solid_green">#f0f0</color> <color name="solid_yellow">#ffffff00</color> </resources>
package com.meng.hellotab; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.widget.TabHost; import android.widget.TextView; import android.app.TabActivity; @SuppressWarnings("deprecation") public class HelloTabActivity extends TabActivity implements TabHost.TabContentFactory { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); TabHost tabHost = getTabHost(); // 不再需要载入布局文件,如果此句不注释掉会导致content的重叠 // LayoutInflater.from(this).inflate(R.layout.activity_hello_tab, // tabHost.getTabContentView(), true); // setContent中传递this tabHost.addTab(tabHost.newTabSpec("tab1") .setIndicator("tab1 indicator").setContent(this)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab2") .setContent(this)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab3") .setContent(this)); } // setContent的参数设为this时,从这个方法得到每一个Tab的内容(此次不用布局文件,用的话会重叠) @Override public View createTabContent(String tag) { // 参数: 这个方法会接受到被选择的tag的标签 final TextView tv = new TextView(this); tv.setText("Content for tab with tag " + tag); return tv; } }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/hello_world" /> <!-- TabHost必须包含一个 TabWidget和一个FrameLayout --> <TabHost android:id="@+id/myTabHost" android:layout_width="match_parent" android:layout_height="match_parent" > <LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <!-- TabWidget的id属性必须为 @android:id/tabs --> <TabWidget android:id="@android:id/tabs" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_weight="0" android:orientation="horizontal" /> <!-- FrameLayout的id属性必须为 @android:id/tabcontent --> <FrameLayout android:id="@android:id/tabcontent" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="0" > <TextView android:id="@+id/view1" android:layout_width="match_parent" android:layout_height="match_parent" android:text="Tab1 Content" /> <TextView android:id="@+id/view2" android:layout_width="match_parent" android:layout_height="match_parent" android:text="Tab2 Content" /> <TextView android:id="@+id/view3" android:layout_width="match_parent" android:layout_height="match_parent" android:text="Tab3 Content" /> </FrameLayout> </LinearLayout> </TabHost> </LinearLayout>
package com.meng.hellotabhost; import android.os.Bundle; import android.app.Activity; import android.view.Menu; import android.widget.TabHost; public class HelloTabHostActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_hello_tab_host); TabHost tabHost = (TabHost) findViewById(R.id.myTabHost); // 如果不是继承TabActivity,则必须在得到tabHost之后,添加标签之前调用tabHost.setup() tabHost.setup(); // 这里content的设置采用了布局文件中的view tabHost.addTab(tabHost.newTabSpec("tab1") .setIndicator("tab1 indicator").setContent(R.id.view1)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab2") .setContent(R.id.view2)); tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab3") .setContent(R.id.view3)); } }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TabHost android:id="@+id/myTabHost" android:layout_width="match_parent" android:layout_height="match_parent" > <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:padding="5dp" > <HorizontalScrollView android:layout_width="match_parent" android:layout_height="wrap_content" android:scrollbars="none" > <TabWidget android:id="@android:id/tabs" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </HorizontalScrollView> <FrameLayout android:id="@android:id/tabcontent" android:layout_width="match_parent" android:layout_height="match_parent" android:padding="5dp" /> </LinearLayout> </TabHost> </LinearLayout>
package com.meng.hellotabscroll; import android.os.Bundle; import android.app.Activity; import android.view.View; import android.widget.TabHost; import android.widget.TextView; public class HelloTabScrollActivity extends Activity implements TabHost.TabContentFactory { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_hello_tab_scroll); // 从布局中获取TabHost并建立 TabHost tabHost = (TabHost) findViewById(R.id.myTabHost); tabHost.setup(); // 加上30个标签 for (int i = 1; i <= 30; i++) { String name = "Tab " + i; tabHost.addTab(tabHost.newTabSpec(name).setIndicator(name) .setContent(this)); } } @Override public View createTabContent(String tag) { final TextView tv = new TextView(this); tv.setText("Content for tab with tag " + tag); return tv; } }