android SlidingTab 开始活动？答案

【问题标题】：android SlidingTab start activity?android SlidingTab 开始活动？
【发布时间】：2016-07-13 03:01:32
【问题描述】：

我有 3 个标签（Slidingtablayout）。左侧选项卡有一个片段，右侧选项卡有一个片段。

但是中间的标签应该开始一个新的活动并且没有片段。这可能吗？我该怎么做？

MainActivity

public class MainActivity extends ActionBarActivity {

MyPageAdapter pagerAdapter;
List<Fragment> fragments;
ViewPager viewPager;
SlidingTabLayout tabLayout;

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

    // initializing SlidiTabLayout
    tabLayout = (SlidingTabLayout) findViewById(R.id.tabLayout);

    // Customizing SlidingTabLayout
    tabLayout.setCustomTabView(R.layout.custom_tab, 0);
    tabLayout.setDistributeEvenly(true);

    // initializing PagerAdapter
    fragments = getFragments();
    pagerAdapter = new MyPageAdapter(getSupportFragmentManager(), fragments, this);

    // initializing ViewPager
    viewPager = (ViewPager) findViewById(R.id.pager);
    viewPager.setAdapter(pageAdapter);


    tabLayout.setViewPager(viewPager);

}
    // adding fagments 
    public List<Fragment> getFragments() {
    List<Fragment> addFragment = new ArrayList<Fragment>();

    addFragment.add(ExampleFragment.newInstance());
    // Activity instead of fragment 
    addFragment.add(Change this .newInstance());
    addFragment.add(ExampleFragment.newInstance());

    return addFragment;
}

MyPagerAdapter

public class MyPageAdapter extends FragmentStatePagerAdapter {

private final List<Fragment> fragments;
private CharSequence Titles[];
private Context context;

int icons [] = {R.drawable.lefticon, R.drawable.middleicon, R.drawable.righticon};
Drawable drawable;

public MyPageAdapter(FragmentManager fm, List<Fragment> fragments, Context context) {
    super(fm);
    this.fragments = fragments;
    this.context = context;
}

@Override
public CharSequence getPageTitle(int position) {
    drawable = context.getResources().getDrawable(icons[position]);
    drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
    SpannableString sb = new SpannableString(" ");
    ImageSpan imageSpan = new ImageSpan(drawable, ImageSpan.ALIGN_BOTTOM);
    sb.setSpan(imageSpan, 0, 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
    return sb;
}
// this.fragments.get(position)
@Override
public Fragment getItem(int position) {
    return this.fragments.get(position);
}

@Override
public int getCount() {
    return this.fragments.size();
}


}

片段的样子：

public class PlayFragment extends Fragment {

public static final String EXTRA_MESSAGE = "EXTRA_MESSAGE";

public static final ExampleFragment newInstance()
{
    PlayFragment mf = new PlayFragment();
    Bundle bd = new Bundle(1);
    mf.setArguments(bd);
    return mf;
}

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState )
{
    View v = inflater.inflate(R.layout.example_fragment, container, false);
    return v;
}
}

SlidingTabLayout

public class SlidingTabLayout extends HorizontalScrollView {
/**
 * Allows complete control over the colors drawn in the tab layout. Set with
 * {@link #setCustomTabColorizer(TabColorizer)}.
 */
public interface TabColorizer {

    /**
     * @return return the color of the indicator used when {@code position} is selected.
     */
    int getIndicatorColor(int position);

}

private static final int TITLE_OFFSET_DIPS = 24;
private static final int TAB_VIEW_PADDING_DIPS = 16;
private static final int TAB_VIEW_TEXT_SIZE_SP = 12;

private int mTitleOffset;

private int mTabViewLayoutId;
private int mTabViewTextViewId;
private boolean mDistributeEvenly;

private ViewPager mViewPager;
private SparseArray<String> mContentDescriptions = new SparseArray<String>();
private ViewPager.OnPageChangeListener mViewPagerPageChangeListener;

private final SlidingTabStrip mTabStrip;

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

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

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

    // Disable the Scroll Bar
    setHorizontalScrollBarEnabled(false);
    // Make sure that the Tab Strips fills this View
    setFillViewport(true);

    mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);

    mTabStrip = new SlidingTabStrip(context);
    addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
}

/**
 * Set the custom {@link TabColorizer} to be used.
 *
 * If you only require simple custmisation then you can use
 * {@link #setSelectedIndicatorColors(int...)} to achieve
 * similar effects.
 */
public void setCustomTabColorizer(TabColorizer tabColorizer) {
    mTabStrip.setCustomTabColorizer(tabColorizer);
}

public void setDistributeEvenly(boolean distributeEvenly) {
    mDistributeEvenly = distributeEvenly;
}

/**
 * Sets the colors to be used for indicating the selected tab. These colors are treated as a
 * circular array. Providing one color will mean that all tabs are indicated with the same color.
 */
public void setSelectedIndicatorColors(int... colors) {
    mTabStrip.setSelectedIndicatorColors(colors);
}

/**
 * Set the {@link ViewPager.OnPageChangeListener}. When using {@link SlidingTabLayout} you are
 * required to set any {@link ViewPager.OnPageChangeListener} through this method. This is so
 * that the layout can update it's scroll position correctly.
 *
 * @see ViewPager#setOnPageChangeListener(ViewPager.OnPageChangeListener)
 */
public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
    mViewPagerPageChangeListener = listener;
}

/**
 * Set the custom layout to be inflated for the tab views.
 *
 * @param layoutResId Layout id to be inflated
 * @param textViewId id of the {@link TextView} in the inflated view
 */
public void setCustomTabView(int layoutResId, int textViewId) {
    mTabViewLayoutId = layoutResId;
    mTabViewTextViewId = textViewId;
}

/**
 * Sets the associated view pager. Note that the assumption here is that the pager content
 * (number of tabs and tab titles) does not change after this call has been made.
 */
public void setViewPager(ViewPager viewPager) {
    mTabStrip.removeAllViews();

    mViewPager = viewPager;
    if (viewPager != null) {
        viewPager.setOnPageChangeListener(new InternalViewPagerListener());
        populateTabStrip();
    }
}

/**
 * Create a default view to be used for tabs. This is called if a custom tab view is not set via
 * {@link #setCustomTabView(int, int)}.
 */
protected TextView createDefaultTabView(Context context) {
    TextView textView = new TextView(context);
    textView.setGravity(Gravity.CENTER);
    textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
    textView.setTypeface(Typeface.DEFAULT_BOLD);
    textView.setLayoutParams(new LinearLayout.LayoutParams(
            ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));

    TypedValue outValue = new TypedValue();
    getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
            outValue, true);
    textView.setBackgroundResource(outValue.resourceId);
    textView.setAllCaps(true);

    int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
    textView.setPadding(padding, padding, padding, padding);

    return textView;
}

private void populateTabStrip() {
    final PagerAdapter adapter = mViewPager.getAdapter();
    final View.OnClickListener tabClickListener = new TabClickListener();
        // adapter.getCount();
    for (int i = 0; i < adapter.getCount(); i++) {
        View tabView = null;
        TextView tabTitleView = null;

        if (mTabViewLayoutId != 0) {
            // If there is a custom tab view layout id set, try and inflate it
            tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip,
                    false);
            tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
        }

        if (tabView == null) {
            tabView = createDefaultTabView(getContext());
        }

        if (tabTitleView == null && TextView.class.isInstance(tabView)) {
            tabTitleView = (TextView) tabView;
        }

        if (mDistributeEvenly) {
            LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams();
            lp.width = 0;
            lp.weight = 1;
        }

        tabTitleView.setText(adapter.getPageTitle(i));
        tabView.setOnClickListener(tabClickListener);
        String desc = mContentDescriptions.get(i, null);
        if (desc != null) {
            tabView.setContentDescription(desc);
        }

        mTabStrip.addView(tabView);
        if (i == mViewPager.getCurrentItem()) {
            tabView.setSelected(true);
        }
    }
}

public void setContentDescription(int i, String desc) {
    mContentDescriptions.put(i, desc);
}

@Override
protected void onAttachedToWindow() {
    super.onAttachedToWindow();

    if (mViewPager != null) {
        scrollToTab(mViewPager.getCurrentItem(), 0);
    }
}

private void scrollToTab(int tabIndex, int positionOffset) {
    final int tabStripChildCount = mTabStrip.getChildCount();
    if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) {
        return;
    }

    View selectedChild = mTabStrip.getChildAt(tabIndex);
    if (selectedChild != null) {
        int targetScrollX = selectedChild.getLeft() + positionOffset;

        if (tabIndex > 0 || positionOffset > 0) {
            // If we're not at the first child and are mid-scroll, make sure we obey the offset
            targetScrollX -= mTitleOffset;
        }

        scrollTo(targetScrollX, 0);
    }
}

private class InternalViewPagerListener implements ViewPager.OnPageChangeListener {
    private int mScrollState;

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        int tabStripChildCount = mTabStrip.getChildCount();
        if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
            return;
        }

        mTabStrip.onViewPagerPageChanged(position, positionOffset);

        View selectedTitle = mTabStrip.getChildAt(position);
        int extraOffset = (selectedTitle != null)
                ? (int) (positionOffset * selectedTitle.getWidth())
                : 0;
        scrollToTab(position, extraOffset);

        if (mViewPagerPageChangeListener != null) {
            mViewPagerPageChangeListener.onPageScrolled(position, positionOffset,
                    positionOffsetPixels);
        }
    }

    @Override
    public void onPageScrollStateChanged(int state) {
        mScrollState = state;

        if (mViewPagerPageChangeListener != null) {
            mViewPagerPageChangeListener.onPageScrollStateChanged(state);
        }
    }

    @Override
    public void onPageSelected(int position) {
        if (mScrollState == ViewPager.SCROLL_STATE_IDLE) {
            mTabStrip.onViewPagerPageChanged(position, 0f);
            scrollToTab(position, 0);
        }
        for (int i = 0; i < mTabStrip.getChildCount(); i++) {
            mTabStrip.getChildAt(i).setSelected(position == i);
        }
        if (mViewPagerPageChangeListener != null) {
            mViewPagerPageChangeListener.onPageSelected(position);
        }
    }

}

private class TabClickListener implements View.OnClickListener {
    @Override
    public void onClick(View v) {
        for (int i = 0; i < mTabStrip.getChildCount(); i++) {
            if (v == mTabStrip.getChildAt(i)) {
                mViewPager.setCurrentItem(i);
                return;
            }
        }
    }
}

}

我也尝试了一些东西。因为我想拥有：

3 个标签
2 个片段
中间的Tab应该没有片段

我在这里编辑了这个方法（MainActivity）：

    // adding fragments 
    public List<Fragment> getFragments() {
    List<Fragment> addFragment = new ArrayList<Fragment>();

    addFragment.add(ExampleFragment.newInstance());
    delete middle fragment
    //addFragment.add(ExampleFragment.newInstance());

    addFragment.add(ExampleFragment.newInstance());

    return addFragment;
}

我删除了一个片段。

这意味着我完成了拥有 2 个片段的目标。

2 个片段检查

因为我只有与片段一样多的标签，这意味着我也只有 2 个标签。

所以我去了 SlidingTabLayout 并改变了这个方法：

我将 for 循环更改为 |i

    private void populateTabStrip() {
    final PagerAdapter adapter = mViewPager.getAdapter();
    final View.OnClickListener tabClickListener = new TabClickListener();
        // 3 instead of adapter.getCount(); | For 3 tabs
    for (int i = 0; i < 3; i++) {
        View tabView = null;
        TextView tabTitleView = null;

        if (mTabViewLayoutId != 0) {
            // If there is a custom tab view layout id set, try and inflate it
            tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip,
                    false);
            tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
        }

        if (tabView == null) {
            tabView = createDefaultTabView(getContext());
        }

        if (tabTitleView == null && TextView.class.isInstance(tabView)) {
            tabTitleView = (TextView) tabView;
        }

        if (mDistributeEvenly) {
            LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams();
            lp.width = 0;
            lp.weight = 1;
        }

        tabTitleView.setText(adapter.getPageTitle(i));
        tabView.setOnClickListener(tabClickListener);
        String desc = mContentDescriptions.get(i, null);
        if (desc != null) {
            tabView.setContentDescription(desc);
        }

        mTabStrip.addView(tabView);
        if (i == mViewPager.getCurrentItem()) {
            tabView.setSelected(true);
        }
    }
}

现在：

3 个标签检查

和

2 SlidingTablayout 检查

但不是

中间的Tab应该没有片段

我有 3 个片段和 3 个选项卡，我删除了一个片段，这导致最后一个片段向上移动了一个位置。现在右片段位于中间片段的位置。现在，当我单击中间选项卡时，我得到了右侧选项卡上的片段。

在这种情况下，我的问题是如何将现在移动到中间选项卡位置的片段返回到右侧选项卡。

希望你明白我想要什么。对不起我的英语不好:)。

【问题讨论】：

标签： android android-fragments tabs

【解决方案1】：

首先，您需要这些片段在 3 个选项卡之间导航。所以我的解决方案是，因为您需要从第二个选项卡启动一个活动，所以使用 3 个片段。是3个片段，所以在中间片段的onResume()方法中使用这段代码：

Intent intent = new Intent(getActivity(), YOUR_ACTIVITY_NAME.class);
startActivity(intent);

这应该带你去一个新的活动。

其次，为第二个选项卡启动 Activity 是您的应用程序的一个非常糟糕的设计。如果您打算在 Play 商店中发布此应用程序，我建议您不要遵循此设计。请改用Navigation Drawer。

【讨论】：

@xDerAhmed 如果对您有帮助，您可以接受答案:)

【解决方案2】：

创建两个片段和一个活动

将活动添加到选项卡，如下所示

TabHost tabHost = getTabHost();
    TabHost.TabSpec spec;
    Intent intent;



    intent = new Intent().setClass(this, SecondActivity.class);
    spec = tabHost.newTabSpec("Second").setIndicator("Second")
                  .setContent(intent);
    tabHost.addTab(spec);

点击下面的链接将活动添加到选项卡。 http://www.technotalkative.com/android-tab-bar-example-1/

【讨论】：