使用fragmentactivity而不是tabactivity的简单选项卡

Question

我试过了http://developer.android.com/guide/tutorials/views/hello-tabwidget.html但它使用了不推荐使用的tabactivity，eclipse建议我使用fragmentactivity，它给了我一个样本（在工具提示上），但我认为它给我的样本真的很大。。我只想要一个简单的标签，就像上面的网址游戏。。关于如何使用fragmentactivity来获得与url完全相同的选项卡（单击选项卡上的按钮不会更改活动；相反，它只会更改显示的内容），有什么示例吗？

仅供参考，以下是eclipse向我建议的示例（通过放大的工具提示）：巨大，不是吗？

@已弃用此类已弃用。新的应用程序应该使用Fragments而不是这个类；为了继续在较旧的设备上运行，您可以使用v4支持库，该库提供片段API，兼容到DONUT。

对于针对HONEYCOMB或更高版本开发的应用程序，选项卡通常使用新的ActionBar.newTab（）和相关API在UI中显示用于将选项卡放置在其操作栏区域内。

TabActivity的替换也可以通过使用TabHost。您需要定义一个正确使用带有TabWidget的TabHost以及显示您的选项卡内容。

一个典型的例子是：

<TabHost
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/tabhost"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <TabWidget
            android:id="@android:id/tabs"
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="0"/>
        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_weight="0"/>
        <FrameLayout
            android:id="@+android:id/realtabcontent"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"/>
    </LinearLayout>
</TabHost>

当用户在选项卡之间切换时，实现需要接管切换显示内容的责任。

import java.util.HashMap;
import com.example.android.supportv4.R;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.view.View;
import android.widget.TabHost;
/**
 * This demonstrates how you can implement switching between the tabs of a
 * TabHost through fragments.  It uses a trick (see the code below) to allow
 * the tabs to switch between fragments instead of simple views.
 */
public class FragmentTabs extends FragmentActivity {
    TabHost mTabHost;
    TabManager mTabManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.fragment_tabs);
        mTabHost = (TabHost)findViewById(android.R.id.tabhost);
        mTabHost.setup();
        mTabManager = new TabManager(this, mTabHost, R.id.realtabcontent);
        mTabManager.addTab(mTabHost.newTabSpec("simple").setIndicator("Simple"),
                FragmentStackSupport.CountingFragment.class, null);
        mTabManager.addTab(mTabHost.newTabSpec("contacts").setIndicator("Contacts"),
                LoaderCursorSupport.CursorLoaderListFragment.class, null);
        mTabManager.addTab(mTabHost.newTabSpec("custom").setIndicator("Custom"),
                LoaderCustomSupport.AppListFragment.class, null);
        mTabManager.addTab(mTabHost.newTabSpec("throttle").setIndicator("Throttle"),
                LoaderThrottleSupport.ThrottledLoaderListFragment.class, null);
        if (savedInstanceState != null) {
            mTabHost.setCurrentTabByTag(savedInstanceState.getString("tab"));
        }
    }
    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putString("tab", mTabHost.getCurrentTabTag());
    }
    /**
     * This is a helper class that implements a generic mechanism for
     * associating fragments with the tabs in a tab host.  It relies on a
     * trick.  Normally a tab host has a simple API for supplying a View or
     * Intent that each tab will show.  This is not sufficient for switching
     * between fragments.  So instead we make the content part of the tab host
     * 0dp high (it is not shown) and the TabManager supplies its own dummy
     * view to show as the tab content.  It listens to changes in tabs, and takes
     * care of switch to the correct fragment shown in a separate content area
     * whenever the selected tab changes.
     */
    public static class TabManager implements TabHost.OnTabChangeListener {
        private final FragmentActivity mActivity;
        private final TabHost mTabHost;
        private final int mContainerId;
        private final HashMap<String, TabInfo> mTabs = new HashMap<String, TabInfo>();
        TabInfo mLastTab;
        static final class TabInfo {
            private final String tag;
            private final Class<?> clss;
            private final Bundle args;
            private Fragment fragment;
            TabInfo(String _tag, Class<?> _class, Bundle _args) {
                tag = _tag;
                clss = _class;
                args = _args;
            }
        }
        static class DummyTabFactory implements TabHost.TabContentFactory {
            private final Context mContext;
            public DummyTabFactory(Context context) {
                mContext = context;
            }
            @Override
            public View createTabContent(String tag) {
                View v = new View(mContext);
                v.setMinimumWidth(0);
                v.setMinimumHeight(0);
                return v;
            }
        }
        public TabManager(FragmentActivity activity, TabHost tabHost, int containerId) {
            mActivity = activity;
            mTabHost = tabHost;
            mContainerId = containerId;
            mTabHost.setOnTabChangedListener(this);
        }
        public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) {
            tabSpec.setContent(new DummyTabFactory(mActivity));
            String tag = tabSpec.getTag();
            TabInfo info = new TabInfo(tag, clss, args);
            // Check to see if we already have a fragment for this tab, probably
            // from a previously saved state.  If so, deactivate it, because our
            // initial state is that a tab isn't shown.
            info.fragment = mActivity.getSupportFragmentManager().findFragmentByTag(tag);
            if (info.fragment != null && !info.fragment.isDetached()) {
                FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
                ft.detach(info.fragment);
                ft.commit();
            }
            mTabs.put(tag, info);
            mTabHost.addTab(tabSpec);
        }
        @Override
        public void onTabChanged(String tabId) {
            TabInfo newTab = mTabs.get(tabId);
            if (mLastTab != newTab) {
                FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
                if (mLastTab != null) {
                    if (mLastTab.fragment != null) {
                        ft.detach(mLastTab.fragment);
                    }
                }
                if (newTab != null) {
                    if (newTab.fragment == null) {
                        newTab.fragment = Fragment.instantiate(mActivity,
                                newTab.clss.getName(), newTab.args);
                        ft.add(mContainerId, newTab.fragment, newTab.tag);
                    } else {
                        ft.attach(newTab.fragment);
                    }
                }
                mLastTab = newTab;
                ft.commit();
                mActivity.getSupportFragmentManager().executePendingTransactions();
            }
        }
    }
}

Answer 1

我认为您需要的是：

http://developer.android.com/guide/topics/fundamentals/fragments.html

下面是一个选项卡式片段活动示例：

https://www.tutlane.com/tutorial/android/android-tabs-with-fragments-and-viewpager/

它涵盖了android的所有基本片段。祝你好运