工具类——Fragment+radiortoup切换

/** * 主界面 底部切换tab工具类 */public class FragmentTabUtils implements RadioGroup.OnCheckedChangeListener {    private List<Fragment> fragments; // 一个tab页面对应一个Fragment    private RadioGroup rgs; // 用于切换tab    private FragmentManager fragmentManager; // Fragment所属的Activity    private int fragmentContentId; // Activity中所要被替换的区域的id    private int currentTab; // 当前Tab页面索引    private Context context;    private OnRgsExtraCheckedChangedListener onRgsExtraCheckedChangedListener; // 用于让调用者在切换tab时候增加新的功能    private ImageView imgLeft;    private ImageView imgRight;    private TextView tvTitle;    private RadioGroup rgMain;    private View view;    /**     * @param fragmentManager     * @param fragments     * @param fragmentContentId     * @param rgs     * @param 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);        showFragment(0);    }    public FragmentTabUtils(FragmentManager fragmentManager, List<Fragment> fragments, int fragmentContentId, RadioGroup rgs) {        this(fragmentManager, fragments, fragmentContentId, rgs, null);    }    @Override    public void onCheckedChanged(RadioGroup radioGroup, int checkedId) {        for (int i = 0; i < rgs.getChildCount(); i++) {            if (rgs.getChildAt(i).getId() == checkedId) {                showFragment(i);                // 如果设置了切换tab额外功能功能接口                if (null != onRgsExtraCheckedChangedListener) {                    onRgsExtraCheckedChangedListener.OnRgsExtraCheckedChanged(radioGroup, checkedId, i);                }            }        }    }    private void showFragment(int i) {        Fragment fragment = fragments.get(i);        FragmentTransaction ft = obtainFragmentTransaction(i);        getCurrentFragment().onStop(); // 暂停当前tab        if (fragment.isAdded()) {            fragment.onStart(); // 启动目标tab的fragment onStart()        } else {            ft.add(fragmentContentId, fragment);            ft.commit();        }        showTab(i); // 显示目标tab    }    /**     * 切换tab     *     * @param idx     */    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; // 更新目标tab为当前tab    }    /**     * 获取一个带动画的FragmentTransaction     *     * @param index     * @return     */    private FragmentTransaction obtainFragmentTransaction(int index) {        FragmentTransaction ft = fragmentManager.beginTransaction();        // 设置切换动画        //********************        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;    }    /**     * 切换tab额外功能功能接口     */    public static interface OnRgsExtraCheckedChangedListener {        public void OnRgsExtraCheckedChanged(RadioGroup radioGroup, int checkedId, int index);    }}