Java Android可滚动标签+；刷卡时的刷卡状态

我正在尝试创建一个包含多个选项卡的应用程序。对于每个选项卡，我使用不同的片段。当我浏览选项卡时，其中的信息正在发生变化

刷卡时如何保存每个选项卡的状态

代码，例如：

MainActivity.java：

package com.tabs.example;

import java.util.Locale;

import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerTabStrip;
import android.support.v4.view.ViewPager;

public class MainActivity extends FragmentActivity {

    SectionsPagerAdapter mSectionsPagerAdapter;
    ViewPager            mViewPager;

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

        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        PagerTabStrip pagerTabStrip = (PagerTabStrip) findViewById(R.id.pager_tab_strip);
        pagerTabStrip.setBackgroundColor(Color.BLACK);
        pagerTabStrip.setTabIndicatorColor(Color.CYAN);
        pagerTabStrip.setTextColor(Color.WHITE);
    }

    public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {

            Fragment fragment;
            switch (position) {
                case 0:
                    fragment = new Fragment1();
                    break;
                case 1:
                    fragment = new Fragment2();
                    break;
                case 2:
                    fragment = new Fragment3();
                    break;
                default:
                    fragment  = null;
                    break;
            }
            return fragment;

        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment1, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv1 = (TextView) root.findViewById(R.id.tv1);
        tv1.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment2 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment2, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv2 = (TextView) root.findViewById(R.id.tv2);
        tv2.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment3 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment3, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv3 = (TextView) root.findViewById(R.id.tv3);
        tv1.setText(time);

        return root;

    }
}

片段1.java：

package com.tabs.example;

import java.util.Locale;

import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerTabStrip;
import android.support.v4.view.ViewPager;

public class MainActivity extends FragmentActivity {

    SectionsPagerAdapter mSectionsPagerAdapter;
    ViewPager            mViewPager;

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

        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        PagerTabStrip pagerTabStrip = (PagerTabStrip) findViewById(R.id.pager_tab_strip);
        pagerTabStrip.setBackgroundColor(Color.BLACK);
        pagerTabStrip.setTabIndicatorColor(Color.CYAN);
        pagerTabStrip.setTextColor(Color.WHITE);
    }

    public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {

            Fragment fragment;
            switch (position) {
                case 0:
                    fragment = new Fragment1();
                    break;
                case 1:
                    fragment = new Fragment2();
                    break;
                case 2:
                    fragment = new Fragment3();
                    break;
                default:
                    fragment  = null;
                    break;
            }
            return fragment;

        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment1, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv1 = (TextView) root.findViewById(R.id.tv1);
        tv1.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment2 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment2, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv2 = (TextView) root.findViewById(R.id.tv2);
        tv2.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment3 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment3, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv3 = (TextView) root.findViewById(R.id.tv3);
        tv1.setText(time);

        return root;

    }
}

片段2.java：

package com.tabs.example;

import java.util.Locale;

import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerTabStrip;
import android.support.v4.view.ViewPager;

public class MainActivity extends FragmentActivity {

    SectionsPagerAdapter mSectionsPagerAdapter;
    ViewPager            mViewPager;

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

        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        PagerTabStrip pagerTabStrip = (PagerTabStrip) findViewById(R.id.pager_tab_strip);
        pagerTabStrip.setBackgroundColor(Color.BLACK);
        pagerTabStrip.setTabIndicatorColor(Color.CYAN);
        pagerTabStrip.setTextColor(Color.WHITE);
    }

    public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {

            Fragment fragment;
            switch (position) {
                case 0:
                    fragment = new Fragment1();
                    break;
                case 1:
                    fragment = new Fragment2();
                    break;
                case 2:
                    fragment = new Fragment3();
                    break;
                default:
                    fragment  = null;
                    break;
            }
            return fragment;

        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment1, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv1 = (TextView) root.findViewById(R.id.tv1);
        tv1.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment2 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment2, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv2 = (TextView) root.findViewById(R.id.tv2);
        tv2.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment3 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment3, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv3 = (TextView) root.findViewById(R.id.tv3);
        tv1.setText(time);

        return root;

    }
}

片段3.java：

package com.tabs.example;

import java.util.Locale;

import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerTabStrip;
import android.support.v4.view.ViewPager;

public class MainActivity extends FragmentActivity {

    SectionsPagerAdapter mSectionsPagerAdapter;
    ViewPager            mViewPager;

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

        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        PagerTabStrip pagerTabStrip = (PagerTabStrip) findViewById(R.id.pager_tab_strip);
        pagerTabStrip.setBackgroundColor(Color.BLACK);
        pagerTabStrip.setTabIndicatorColor(Color.CYAN);
        pagerTabStrip.setTextColor(Color.WHITE);
    }

    public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {

            Fragment fragment;
            switch (position) {
                case 0:
                    fragment = new Fragment1();
                    break;
                case 1:
                    fragment = new Fragment2();
                    break;
                case 2:
                    fragment = new Fragment3();
                    break;
                default:
                    fragment  = null;
                    break;
            }
            return fragment;

        }

        @Override
        public int getCount() {
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment1, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv1 = (TextView) root.findViewById(R.id.tv1);
        tv1.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment2 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment2, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv2 = (TextView) root.findViewById(R.id.tv2);
        tv2.setText(time);

        return root;

    }
}

package com.tabs.example;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Fragment3 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment3, container, false);

        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
        Date date = new Date();
        String time = dateFormat.format(date);

        TextView tv3 = (TextView) root.findViewById(R.id.tv3);
        tv1.setText(time);

        return root;

    }
}

---

您可以通过如下设置ViewPagerAdapter来缓存它们：

mViewPager.setOffscreenPageLimit(3);

---

你说的拯救国家是什么意思？您可以通过如下设置ViewPagerAdapter来缓存它们：mViewPager.setOffscreenPageLimit（3）；我想在滑动到第三个标签并返回到第一个被按住的时间时，在那里，在那里。当你改变屏幕方向时，一切都保持了改变前的状态。可能是我非常想？）mviewpage.setOffscreenPageLimit（3）；我会稍后再试，谢谢你是的，如果你设置了页面限制来包括你所有的标签页，假设它们是一个列表，然后你向下滑动列表，然后你回到它，位置仍然会保持在wangyif2，谢谢你！这是工作。我怎么能对你说“谢谢”？添加回复，我接受了他的回复并提供帮助我想在选项卡上方添加标题部分，我该怎么做？