拖放操作栏选项卡（Android 4.0 ICS）？

Question

有没有办法允许用户拖放ActionBar中的导航选项卡以在Android 4.0 ICS上对其进行重新排序？我并不是指在已弃用的TabHost中选项卡，而是指添加到在Honeycomb中使用的ActionBar的选项卡。

谢谢！

Answer 1

至于使用ActionBar.Tabs去，他们根本没有功能来实现这一点。另一方面，创建模拟Tabs的自定义类很容易，那么您只需创建并添加OnDragListener和OnTouchListener即可用于填充选项卡栏的View。

例如，这是我在其中一个模拟ActionBar.Tabs的应用程序中使用的类。

ScrollableTabView

public class ScrollableTabView extends HorizontalScrollView implements OnPageChangeListener { 

    private final Context mContext; 

    private final LinearLayout mContainer; 

    private final ArrayList<View> mTabs = new ArrayList<View>(); 

    private final int mDividerColor = 0xFF636363; 

    private int mDividerMarginTop = 12; 

    private int mDividerMarginBottom = 12; 

    private int mDividerWidth = 1; 

    private ViewPager mPager; 

    private TabAdapter mAdapter; 

    private Drawable mDividerDrawable; 

    public ScrollableTabView(Context context) { 
     this(context, null); 
    } 

    public ScrollableTabView(Context context, AttributeSet attrs) { 
     this(context, attrs, 0); 
    } 

    public ScrollableTabView(Context context, AttributeSet attrs, int defStyle) { 
     super(context, attrs); 

     mContext = context; 

     final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
       android.view.ViewGroup.LayoutParams.MATCH_PARENT, 
       android.view.ViewGroup.LayoutParams.MATCH_PARENT); 

     mDividerMarginTop = (int)(getResources().getDisplayMetrics().density * mDividerMarginTop); 
     mDividerMarginBottom = (int)(getResources().getDisplayMetrics().density * mDividerMarginBottom); 
     mDividerWidth = (int)(getResources().getDisplayMetrics().density * mDividerWidth); 

     setHorizontalScrollBarEnabled(false); 
     setHorizontalFadingEdgeEnabled(false); 

     mContainer = new LinearLayout(context); 
     mContainer.setOrientation(LinearLayout.HORIZONTAL); 
     mContainer.setLayoutParams(params); 

     addView(mContainer); 
    } 

    /** 
    * Set the tabs Adapter 
    * 
    * @param adapter 
    */ 
    public void setAdapter(TabAdapter adapter) { 
     mAdapter = adapter; 

     if (mPager != null && mAdapter != null) { 
      initTabs(); 
     } 
    } 

    /** 
    * Attach ViewPager 
    * 
    * @param pager 
    */ 
    public void setViewPager(ViewPager pager) { 
     mPager = pager; 
     mPager.setOnPageChangeListener(this); 

     if (mPager != null && mAdapter != null) { 
      initTabs(); 
     } 
    } 

    /** 
    * Initiate the tabs 
    */ 
    private void initTabs() { 

     mContainer.removeAllViews(); 
     mTabs.clear(); 

     if (mAdapter == null) { 
      return; 
     } 

     for (int i = 0; i < mPager.getAdapter().getCount(); i++) { 

      final int index = i; 

      final View tab = mAdapter.getView(i); 
      mContainer.addView(tab); 

      tab.setFocusable(true); 

      mTabs.add(tab); 

      if (i != mPager.getAdapter().getCount() - 1) { 
       mContainer.addView(getSeparator()); 
      } 

      tab.setOnClickListener(new OnClickListener() { 
       @Override 
       public void onClick(View v) { 
        if (mPager.getCurrentItem() == index) { 
         selectTab(index); 
        } else { 
         mPager.setCurrentItem(index, true); 
        } 
       } 
      }); 

     } 

     selectTab(mPager.getCurrentItem()); 
    } 

    @Override 
    public void onPageScrollStateChanged(int state) { 
     // Nothing to do 
    } 

    @Override 
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { 
     // Nothing to do 
    } 

    @Override 
    public void onPageSelected(int position) { 
     selectTab(position); 
    } 

    @Override 
    protected void onLayout(boolean changed, int l, int t, int r, int b) { 
     super.onLayout(changed, l, t, r, b); 

     if (changed) { 
      selectTab(mPager.getCurrentItem()); 
     } 
    } 

    /** 
    * @return Separates the tabs 
    */ 
    private View getSeparator() { 
     final View v = new View(mContext); 

     final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(mDividerWidth, 
       android.view.ViewGroup.LayoutParams.MATCH_PARENT); 
     params.setMargins(0, mDividerMarginTop, 0, mDividerMarginBottom); 
     v.setLayoutParams(params); 

     if (mDividerDrawable != null) { 
      v.setBackground(mDividerDrawable); 
     } else { 
      v.setBackgroundColor(mDividerColor); 
     } 

     return v; 
    } 

    /** 
    * @param position 
    */ 
    private void selectTab(int position) { 

     for (int i = 0, pos = 0; i < mContainer.getChildCount(); i += 2, pos++) { 
      final View tab = mContainer.getChildAt(i); 
      tab.setSelected(pos == position); 
     } 

     final View selectedTab = mContainer.getChildAt(position * 2); 

     final int w = selectedTab.getMeasuredWidth(); 
     final int l = selectedTab.getLeft(); 

     final int x = l - this.getWidth()/2 + w/2; 

     smoothScrollTo(x, this.getScrollY()); 
    } 
} 

TabAdapter

public interface TabAdapter { 
    public View getView(int position); 
} 

附上您的TabAdapter

public class ScrollingTabsAdapter implements TabAdapter { 

    private final FragmentActivity activity; 

    private final LayoutInflater inflater; 

    private Button mTabs; 

    // Tab titles 
    private static final String[] mTitles = { 
      "RECENT", "ARTISTS", "ALBUMS", "SONGS", "PLAYLISTS", "GENRES" 
    }; 

    /** 
    * @param act 
    */ 
    public ScrollingTabsAdapter(FragmentActivity act) { 
     activity = act; 
     inflater = activity.getLayoutInflater(); 
    } 

    @Override 
    public View getView(int position) { 
     mTabs = (Button)inflater.inflate(R.layout.tabs, null); 
     if (position < mTitles.length) { 
      mTabs.setText(mTitles[position]); 
     } 
     return mTabs; 
    } 
} 

你可以使用默认的可绘制的和真实的ActionBar.Tabs的属性来设计你膨胀的Button。你可以从SDK中抓取它们，或者在网络上的某个地方抓取它们。要使用它，请将ViewPager对象附加到ScrollableTabView，并在FragmentPagerAdapter中添加您的每个Fragments。 This is what they look like, if you're curious about the style after adding the default drawables and attributes

就拖放而言，Android在其网站上有一些不错的文档。 Drag and Drop

在网络上也有一些易于使用的教​​程。 Android Drag and Drop Tutorial, via Lars Vogel

Or you can always simply use Google to find more