android - 选项卡 fragment - 选项卡随 fragment 侧面的按钮操作而变化

Question

我正在使用 TabsPagerAdapter 开发 ViewPager，我已经成功创建了两个选项卡，例如 a 和 b。我的按钮被放置在选项卡中，如果我单击按钮，它必须放置在选项卡中。

主要 Activity 是 -

private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Top Rated", "Games" };

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

    // Initilization
    viewPager = (ViewPager) findViewById(R.id.pager);
    actionBar = getActionBar();
    mAdapter = new TabsPagerAdapter(getSupportFragmentManager());

    viewPager.setAdapter(mAdapter);
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);        

    // Adding Tabs
    for (String tab_name : tabs) {
        actionBar.addTab(actionBar.newTab().setText(tab_name)
                .setTabListener(this));
    }

    /**
     * on swiping the viewpager make respective tab selected
     * */
    viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {

        @Override
        public void onPageSelected(int position) {
            // on changing the page
            // make respected tab selected
            actionBar.setSelectedNavigationItem(position);
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {
        }

        @Override
        public void onPageScrollStateChanged(int arg0) {
        }
    });
}

@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}

@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
    // on tab selected
    // show respected fragment view
    viewPager.setCurrentItem(tab.getPosition());
}

@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}}

Tabpageadaper 是 -

public class TabsPagerAdapter extends FragmentPagerAdapter {

public TabsPagerAdapter(FragmentManager fm) {
    super(fm);
}

@Override
public Fragment getItem(int index) {

    switch (index) {
    case 0:
        // Top Rated fragment activity
        return new TopRatedFragment();
    case 1:
        // Games fragment activity
        return new GamesFragment();
    case 2:
        // Movies fragment activity
        return new MoviesFragment();
    }

    return null;
}

@Override
public int getCount() {
    // get item count - equal to number of tabs
    return 3;
}

}

我的按钮位于“最高评价”选项卡中，如下所示 -

public class TopRatedFragment extends Fragment {
private int currentPage;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_top_rated, container, false);
    Button b1=(Button)rootView.findViewById(R.id.button);
    b1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
        }
    });
    return rootView;
}

}

当我单击上面的按钮时，它必须打开游戏选项卡。提前致谢。

Answer 1

要更改Tab/Fragment，您可以使用viewPager.setCurrentItem()方法。

1. 在 MainActivity.java 中编写一个 public 方法，如下所示:

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
   
       ................
       ........................
   }
   
   public void selectTab(int position) {
       viewPager.setCurrentItem(position);
   }
   

2. 使用 TopRatedFragment.java 中的 selectTab() 方法选择 GamesFragment。

   @Override
   public View onCreateView(LayoutInflater inflater, ViewGroup container,
                        Bundle savedInstanceState) {
   
       View rootView = inflater.inflate(R.layout.fragment_top_rated, container, false);
       Button b1=(Button)rootView.findViewById(R.id.button);
       b1.setOnClickListener(new View.OnClickListener() {
           @Override
           public void onClick(View view) {
               ((MainActivity)getActivity()).selectTab(1); // 1 for GamesFragment
           }
       });
   
       return rootView;
   }