FragmentTabUtils.java

package forezp.com.douyalibrary.utils;



import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.widget.RadioButton;
import android.widget.RadioGroup;

import java.util.List;


public class FragmentTabUtils implements RadioGroup.OnCheckedChangeListener {
    private List<Fragment> fragments;
    private RadioGroup rgs;
    private FragmentManager fragmentManager;
    private int fragmentContentId;
    private int currentTab;
    private OnRgsExtraCheckedChangedListener onRgsExtraCheckedChangedListener;

    public FragmentTabUtils(FragmentManager fragmentManager, List<Fragment> fragments, int fragmentContentId, RadioGroup rgs, OnRgsExtraCheckedChangedListener onRgsExtraCheckedChangedListener) {
        this.fragments = fragments;
        this.rgs = rgs;
        this.fragmentManager = fragmentManager;
        this.fragmentContentId = fragmentContentId;
        this.onRgsExtraCheckedChangedListener = onRgsExtraCheckedChangedListener;
        rgs.setOnCheckedChangeListener(this);
        ((RadioButton) rgs.getChildAt(0)).setChecked(true);

    }

    @Override
    public void onCheckedChanged(RadioGroup radioGroup, int checkedId) {
        for (int i = 0; i < rgs.getChildCount(); i++) {
            if (rgs.getChildAt(i).getId() == checkedId) {
                Fragment fragment = fragments.get(i);
                FragmentTransaction ft = obtainFragmentTransaction(i);
                getCurrentFragment().onStop();
                if (fragment.isAdded()) {
                    fragment.onStart();
                } else {
                    ft.add(fragmentContentId, fragment, String.valueOf(i));
                    ft.commit();
                }
                showTab(i);
                if (null != onRgsExtraCheckedChangedListener) {
                    onRgsExtraCheckedChangedListener.OnRgsExtraCheckedChanged(radioGroup, checkedId, i);
                }
            }
        }

    }

    private void showTab(int idx) {
        for (int i = 0; i < fragments.size(); i++) {
            Fragment fragment = fragments.get(i);
            FragmentTransaction ft = obtainFragmentTransaction(idx);
            if (idx == i) {
                ft.show(fragment);
            } else {
                ft.hide(fragment);
            }
            ft.commit();
        }
        currentTab = idx;
    }


    private FragmentTransaction obtainFragmentTransaction(int index) {
        FragmentTransaction ft = fragmentManager.beginTransaction();

        return ft;
    }


    public int getCurrentTab() {
        return currentTab;
    }

    public Fragment getCurrentFragment() {
        return fragments.get(currentTab);
    }

    public OnRgsExtraCheckedChangedListener getOnRgsExtraCheckedChangedListener() {
        return onRgsExtraCheckedChangedListener;
    }

    public void setOnRgsExtraCheckedChangedListener(OnRgsExtraCheckedChangedListener onRgsExtraCheckedChangedListener) {
        this.onRgsExtraCheckedChangedListener = onRgsExtraCheckedChangedListener;
    }


    public static interface OnRgsExtraCheckedChangedListener {
        public void OnRgsExtraCheckedChanged(RadioGroup radioGroup, int checkedId, int index);
    }
}