如何在swipe上更新viewpager的视图 - android

Question

我正在使用view-pager.In我有三个标签:1.历史,2.主要,3.地图.

我有秒表到主activity.When我按下启动,然后在秒表的那段时间值停止后加入到sqlite的DB.在历史活动中,我从数据库获取秒表的值并存储到列表视图中.它的工作完美.

但是,当我从Main> History中滑动时,我想要更新History活动,所以在按下停止按钮后,我将最后一个值输入到历史活动的listview中.

我的问题是 how can I update the view on swipe the viewpager?

public class SwipeyTabsSampleActivity extends FragmentActivity {

private static final String [] TITLES = {
    "HISTORY", 
    "MAIN",
    "MAP"  

};

private SwipeyTabs mTabs;
private ViewPager mViewPager;
//Handler handler=new Handler();

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_swipeytab);

    mViewPager = (ViewPager) findViewById(R.id.viewpager);
    mTabs = (SwipeyTabs) findViewById(R.id.swipeytabs);

    SwipeyTabsPagerAdapter adapter = new SwipeyTabsPagerAdapter(this,
            getSupportFragmentManager());
    mViewPager.setAdapter(adapter);
    mTabs.setAdapter(adapter);
    mViewPager.setOnPageChangeListener(mTabs);
    mViewPager.setCurrentItem(1); 
    mViewPager.setOffscreenPageLimit(3);


}

 private class SwipeyTabsPagerAdapter extends FragmentPagerAdapter implements
        SwipeyTabsAdapter, ViewPager.OnPageChangeListener {

    private final Context mContext;
    ViewPager viewpager;



    public SwipeyTabsPagerAdapter(Context context, FragmentManager fm, ViewPager mViewPager) {
        super(fm);

        this.mContext = context;
        viewpager = mViewPager;

        //viewpager.setAdapter(this);
        viewpager.setOnPageChangeListener(this);

    }

    @Override
    public Fragment getItem(int position) {

         Fragment f = new Fragment();

        switch (position) {
        case 0:
            f = History.newInstance(position);

            break;
        case 1:
            f = Main.newInstance(position);
            break;
        case 2:
            f = Map.newInstance(position);

            break;

        }
        return f;

    }

    @Override
    public int getCount() {
        return TITLES.length;
    }


     @Override
        public void destroyItem(ViewGroup container, int position, Object object) {

            ViewPager pager = (ViewPager) container;
            View view = (View) object;

            pager.removeView(view);
        }



    public TextView getTab(final int position, SwipeyTabs root) {
        TextView view = (TextView) LayoutInflater.from(mContext).inflate(
                R.layout.swipey_tab_indicator, root, false);
        view.setText(TITLES[position]);
        view.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                mViewPager.setCurrentItem(position);

            }
        });

        return view;
    }

    @Override
    public void onPageScrollStateChanged(int state) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onPageSelected(int positiion) {
        // TODO Auto-generated method stub

    }

}

}

Answer 1

添加ViewPager OnPageChangeListener:

mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(int position) {
            // your code here
        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    });

Answer 2

取一根字符串并将 Getter 和 Setter 添加到您的FragmentActivity类中。

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String HistoryFragment;

public String getHistoryFragment() {
    return HistoryFragment;
}


public void setHistoryFragment(String historyFragment) {
    HistoryFragment = historyFragment;
}

然后我们可以通过调用从当前片段访问另一个片段findFragmentByTag(<tag of target fragment>)。

有关更多信息，请检查链接ViewPager 中片段之间的通信。