TabHost中的Horizo​​ntalScrollView在末尾添加额外的空间

Question

为了在片段之间轻松切换，我将Horizo​​ntalScrollView嵌入到我的Tab布局中，如下所示：

<?xml version="1.0" encoding="utf-8"?>
<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">

        <HorizontalScrollView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:fillViewport="true"
            android:scrollbars="none" >

            <TabWidget android:id="@android:id/tabs" 
                android:layout_height="wrap_content" 
                android:layout_width="wrap_content">
            </TabWidget>
        </HorizontalScrollView>
        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </LinearLayout>
</TabHost>

但是在我的代码中添加了Fragments（如下所示）之后，在Horizo​​ntalScrollView的末尾突然出现了一些额外的空格：

滚动前

滚动后

代码非常复杂，但我会尝试展示重要的部分。

{
    mTabHost = (TabHost) childLayout.findViewById(android.R.id.tabhost);
    mTabHost.setup();
    FrameLayout tabsFL = (FrameLayout) childLayout.findViewById(android.R.id.tabcontent);
    tabsFL.setId(TABS_FRAME_ID);

    for (int i = 0; i < list.size(); i++) {
        mTabHost.addTab(newTab(String.valueOf(i), list.get(i).getTitle(), tabsFL.getId()));
    }

    mTabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
        @Override
        public void onTabChanged(String tabId) {
        updateTab(tabId, Integer.parseInt(tabId), list);
        }
    });

    //manually load first fragment
    mTabHost.setCurrentTab(mCurrentTab);
    updateTab(String.valueOf(mCurrentTab), mCurrentTab, list);
}


private TabSpec newTab(String tag, String tabLabel, int tabContentId) {
    int count = Integer.parseInt(tag);
    count +=1;

    View indicator = inflater.inflate(R.layout.details_tab,
        (ViewGroup) childLayout.findViewById(android.R.id.tabs), false);
    ((TextView) indicator.findViewById(R.id.text)).setText(count + ". " + tabLabel);

    TabSpec tabSpec = mTabHost.newTabSpec(tag);
    tabSpec.setIndicator(indicator);
    tabSpec.setContent(tabContentId);
    return tabSpec;
}

private void updateTab(String tabId, int id, ArrayList<CustomObject> frags) {
    mCurrentTab = id;

    FragmentManager fm = activity.getSupportFragmentManager();
    fm.beginTransaction()
        .replace(TABS_FRAME_ID, DetailsFragment.newInstance(frags.get(id)), tabId)
        .commitAllowingStateLoss();
}

也是无关的，但我也有一个问题，第一个标签没有手动加载（点击标签完美加载片段，只是因为某种原因第一个没有加载）。

Answer 1

TabWidget默认将measureWithLargestChild设置为true，这意味着它使用最宽的选项卡来计算TabWidget在测量自身时使用的内部LinearLayout的总宽度。如果您的标签长度​​不同，这将导致内部LinearLayout在较短标签与最宽标签之间的差异末端有一些额外空间。如果您将android:measureWithLargestChild="false"添加到TabWidget布局，它应该可以解决您的问题。

tl; dr 将您的布局TabWidget更改为：

<TabWidget android:id="@android:id/tabs" 
    android:layout_height="wrap_content" 
    android:layout_width="wrap_content"
    android:measureWithLargestChild="false">
</TabWidget>

Answer 2

我认为你手动添加tabhost就像..

@SuppressLint("ResourceAsColor")
public class MainActivity extends FragmentActivity implements
    OnTabChangeListener, OnPageChangeListener {

MyPageAdapter pageAdapter;
private ViewPager mViewPager;
private TabHost mTabHost;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mViewPager = (ViewPager) findViewById(R.id.viewpager);

    // Tab Initialization
    initialiseTabHost();

    // Fragments and ViewPager Initialization
    List<Fragment> fragments = getFragments();
    pageAdapter = new MyPageAdapter(getSupportFragmentManager(), fragments);
    mViewPager.setAdapter(pageAdapter);
    mViewPager.setOnPageChangeListener(MainActivity.this);
}

// Method to add a TabHost
private static void AddTab(MainActivity activity, TabHost tabHost,
        TabHost.TabSpec tabSpec) {
    tabSpec.setContent(new MyTabFactory(activity));
    tabHost.addTab(tabSpec);
}

// Manages the Tab changes, synchronizing it with Pages
public void onTabChanged(String tag) {
    int pos = this.mTabHost.getCurrentTab();
    this.mViewPager.setCurrentItem(pos);
    // mTabHost.getTabWidget().setDividerDrawable(null);
    setSelectedTabColor();
}

@Override
public void onPageScrollStateChanged(int arg0) {
}

// Manages the Page changes, synchronizing it with Tabs
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
    int pos = this.mViewPager.getCurrentItem();
    this.mTabHost.setCurrentTab(pos);
    // mTabHost.getTabWidget().setDividerDrawable(null);
}

@Override
public void onPageSelected(int arg0) {
}

@SuppressLint("ResourceAsColor")
private void setSelectedTabColor() {
    for (int i = 0; i < mTabHost.getTabWidget().getChildCount(); i++) {
        mTabHost.getTabWidget().setDividerDrawable(
                android.R.color.transparent);
        TextView tv = (TextView) mTabHost.getTabWidget().getChildAt(i)
                .findViewById(android.R.id.title);
        tv.setTextColor(getResources().getColor(R.color.white));
        mTabHost.getTabWidget()
                .setShowDividers(TabWidget.SHOW_DIVIDER_NONE);
        mTabHost.getTabWidget().getChildAt(i)
                .setBackgroundColor(R.drawable.bottom_home_back);
        // mTabHost.getTabWidget().getChildAt(0).getLayoutParams().width =
        // 50;
    }
    mTabHost.getTabWidget().getChildAt(mTabHost.getCurrentTab())
            .setBackgroundResource(R.drawable.btn_selected);
    // mTabHost.getTabWidget().getChildAt(0).getLayoutParams().width = 50;
}

private List<Fragment> getFragments() {
    List<Fragment> fList = new ArrayList<Fragment>();

    // TODO Put here your Fragments
    // DealTab f1 = DealTab.newInstance();
    DealTab_New f1 = DealTab_New.newInstance();
    EventTab f2 = EventTab.newInstance();

    MyAccountFragment f3 = MyAccountFragment.newInstance();
    MessageFragment f4 = MessageFragment.newInstance();
    MoreFragment f5 = MoreFragment.newInstance();
    QrCodeFragment f6 = QrCodeFragment.newInstance();

    // fList.add(f1);
    fList.add(f1);
    fList.add(f2);
    fList.add(f3);
    fList.add(f4);
    fList.add(f5);
    fList.add(f6);

    return fList;
}

// Tabs Creation
@SuppressLint("ResourceAsColor")
private void initialiseTabHost() {
    mTabHost = (TabHost) findViewById(android.R.id.tabhost);
    mTabHost.setup();

    // TODO Put here your Tabs
    MainActivity.AddTab(
            this,
            this.mTabHost,
            this.mTabHost.newTabSpec("Tab1").setIndicator(
                    "",
                    getApplicationContext().getResources().getDrawable(
                            R.drawable.btn_deals)));


    MainActivity.AddTab(
            this,
            this.mTabHost,
            this.mTabHost.newTabSpec("Tab2").setIndicator(
                    "",
                    getApplicationContext().getResources().getDrawable(
                            R.drawable.btn_event)));
    MainActivity.AddTab(
            this,
            this.mTabHost,
            this.mTabHost.newTabSpec("Tab3").setIndicator(
                    "",
                    getApplicationContext().getResources().getDrawable(
                            R.drawable.btn_my_account)));
    MainActivity.AddTab(
            this,
            this.mTabHost,
            this.mTabHost.newTabSpec("Tab4").setIndicator(
                    "",
                    getApplicationContext().getResources().getDrawable(
                            R.drawable.btn_message)));
    MainActivity.AddTab(
            this,
            this.mTabHost,
            this.mTabHost.newTabSpec("Tab5").setIndicator(
                    "",
                    getApplicationContext().getResources().getDrawable(
                            R.drawable.btn_more)));

    mTabHost.setOnTabChangedListener(this);

    setSelectedTabColor();
}
}

在这段代码中，我手动添加了tab键，并在片段上加载了它。