Fragment动态实现导航栏

首先建立四个fragment_tem分别继承fragment,如下：

public class HalfyearFragment extends Fragment {
    public Context mContext=getActivity();
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
       View myview =inflater.inflate(R.layout.examine_halfyearfragment,container,false);
       return myview;
    }
}

HalfyearFragment继承了Fragment，并且绑定了xml。

然后在MainActivity中使用，就可以实现了。

@BindView(R.id.month_examine)
Button monthExamine;
@BindView(R.id.quarter_examine)
Button quarterExamine;
@BindView(R.id.Halfyear_examine)
Button HalfyearExamine;
@BindView(R.id.Oneyear_examine)
Button OneyearExamine;


private ArrayList<Fragment> fragments = new ArrayList<>();
private int position;
private Fragment mContext;


@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.examine_main);
    ButterKnife.bind(this);
    initFragment();
    initListener();

}

private void initFragment() {
    fragments = new ArrayList<>();
    fragments.add(new MonthFragment());
    fragments.add(new QuaterFragment());
    fragments.add(new HalfyearFragment());
    fragments.add(new OneYearFragment());
}

private void initListener() {
    examineGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup group, int checkedId) {
            switch (checkedId) {
                case R.id.e_month:
                    position = 0;
                    break;
                case R.id.e_quarter:
                    position = 1;
                    break;
                case R.id.e_halfyear:
                    position = 2;
                    break;
                case R.id.e_year:
                    position = 3;
                    break;
            }
            Fragment baseFragment = getFragment(position);
            switchFragment(mContext, baseFragment);
        }
    });
    examineGroup.check(R.id.e_month);
}

private Fragment getFragment(int position) {
    if (fragments != null && fragments.size() > 0) {
        Fragment baseFragment = fragments.get(position);
        return baseFragment;
    }
    return null;
}

private void switchFragment(Fragment formFragment, Fragment nextFragment) {
    if (mContext != nextFragment) {
        mContext = nextFragment;
        if (nextFragment != null) {
            FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
            //判断nextFragment是否添加
            if (!nextFragment.isAdded()) { //隐藏当前Fragment
                if (formFragment != null) {
                    transaction.hide(formFragment);
                }

                transaction.add(R.id.content, nextFragment).commit();
            } else {
                //隐藏当前Fragment
                if (formFragment != null) {
                    transaction.hide(formFragment);
                }
                transaction.show(nextFragment).commit();
            }
        }
    }

学习过程中参考了两个网站：

https://www.jianshu.com/p/28ca4cbe190c

https://blog.csdn.net/qq_34861102/article/details/76737673