Android activity+tabLayout+viewPager+fragment完美的解决传值问题
Android tabLayout+viewPager+fragment处理懒加载
Android 关于动态设置tab显示和隐藏问题

在项目实战中，大家或许都遇到过，在fragment中写数据接口。每次点击切换对应的fragment加载数据都有问题。

在TabLayout上点击不相邻两个Fragment时候,加载数据加载两次, 而且加载按钮会一直加载.
场景:
Adapter : FramgmentPagerAdapter
点击不相邻的Fragment时候, 数据重复加载.

解决办法：

Android tabLayout+viewPager+fragment处理懒加载

这里总结一篇另外一种方式：

从图2中不难看出，主要处理是在TabAcitvity和TabFragment中做的处理，下面把代码粘贴出来

TabActivity.class

/**
 * @author 拉莫帅
 * @date 2022/4/2
 * @address
 * @Desc 选项卡
 */
public class TabActivity extends BaseActivity {

    private View view;
    private TabFragment tabFragment;
    private RelativeLayout baseTitle;

    @Override
    protected BasePresenter createPresenter() {
        return null;
    }

    //初始化布局
    @Override
    protected View addContentLayout() {
        view = getLayoutInflater().inflate(R.layout.activity_tab, baseLayout, false);
        return view;
    }

    //初始化控件
    @Override
    protected void initView() {
        baseTitle = findViewById(R.id.baseTitle);
    }

    @Override
    protected void initListener() {

    }

    //初始化数据
    @Override
    protected void initDatas() {
        baseTitle.setVisibility(View.GONE);
        tabFragment = new TabFragment();
        FragmentManager fragmentManager = getSupportFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.add(R.id.ll_ment_top, tabFragment);
        fragmentTransaction.commit();
    }
}

activity_tab.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/tab_view" />

    <LinearLayout
        android:id="@+id/ll_ment_top"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:orientation="horizontal">

    </LinearLayout>

    <LinearLayout
        android:id="@+id/ll_ment_bottom"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="12"
        android:orientation="vertical">

    </LinearLayout>
</LinearLayout>

资源文件：

<color name="tab_view">#EEEEEE </color>
<color name="main_color">#02C5AF</color>
<color name="home_default_text">#999999</color>

tab_button.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
    <corners
        android:topLeftRadius="25dp"
        android:topRightRadius="25dp"
        android:bottomLeftRadius="25dp"
        android:bottomRightRadius="25dp"/>
    <solid android:color="@color/main_color"/><!-- 填充颜色 -->

    <stroke android:width="0.1mm" android:color="@color/main_color" /><!-- 描边，边框宽度、颜色 -->
</shape>

TabFragment.class

/**
 * @author Martin-harry 
 * @date 2022/4/2
 * @address
 * @Desc TabFragment
 */
public class TabFragment extends Fragment implements View.OnClickListener {

    private View view;
    private Context mContext;
    private FirstFragment firstFragment;
    private SecondFragment secondFragment;
    private ThirdFragment thirdFragment;
    private RelativeLayout rl_first, rl_second, rl_third;
    private TextView tv_first, tv_second, tv_third;
    private View view_one, view_two, view_three;
    private FragmentManager fragmentManager;
    private FragmentTransaction transaction;

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.mContext = context;
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        view = inflater.inflate(R.layout.fragment_tab, container, false);
        initViews();
        return view;
    }

    private void hideFragment(FragmentTransaction transaction) {
        if (firstFragment != null) {
            transaction.hide(firstFragment);
        }
        if (secondFragment != null) {
            transaction.hide(secondFragment);
        }
        if (thirdFragment != null) {
            transaction.hide(thirdFragment);
        }
    }

    private void initViews() {

        rl_first = view.findViewById(R.id.rl_first);
        rl_second = view.findViewById(R.id.rl_second);
        rl_third = view.findViewById(R.id.rl_third);
        rl_first.setOnClickListener(this);
        rl_second.setOnClickListener(this);
        rl_third.setOnClickListener(this);

        tv_first = view.findViewById(R.id.tv_first);
        tv_second = view.findViewById(R.id.tv_second);
        tv_third = view.findViewById(R.id.tv_third);
        view_one = view.findViewById(R.id.view_one);
        view_two = view.findViewById(R.id.view_two);
        view_three = view.findViewById(R.id.view_three);

        view_one.setVisibility(View.VISIBLE);
        view_two.setVisibility(View.GONE);
        view_three.setVisibility(View.GONE);
        tv_first.setTextColor(this.getResources().getColor(R.color.main_color));
        tv_second.setTextColor(this.getResources().getColor(R.color.home_default_text));
        tv_third.setTextColor(this.getResources().getColor(R.color.home_default_text));

        fragmentManager = getFragmentManager();
        transaction = fragmentManager.beginTransaction();
        firstFragment = new FirstFragment();
        transaction.add(R.id.ll_ment_bottom, firstFragment);
        transaction.commit();
        rl_first.setEnabled(false);
        rl_second.setEnabled(true);
        rl_third.setEnabled(true);
    }

    @Override
    public void onClick(View v) {
        transaction = fragmentManager.beginTransaction();
        hideFragment(transaction);
        switch (v.getId()) {
            case R.id.rl_first:
                view_one.setVisibility(View.VISIBLE);
                view_two.setVisibility(View.GONE);
                view_three.setVisibility(View.GONE);
                tv_first.setTextColor(this.getResources().getColor(R.color.main_color));
                tv_second.setTextColor(this.getResources().getColor(R.color.home_default_text));
                tv_third.setTextColor(this.getResources().getColor(R.color.home_default_text));
                if (firstFragment == null) {
                    firstFragment = new FirstFragment();
                    transaction.add(R.id.ll_ment_bottom, firstFragment);
                } else {
                    transaction.show(firstFragment);
                }
                rl_first.setEnabled(false);
                rl_second.setEnabled(true);
                rl_third.setEnabled(true);
                break;
            case R.id.rl_second:
                view_one.setVisibility(View.GONE);
                view_two.setVisibility(View.VISIBLE);
                view_three.setVisibility(View.GONE);
                tv_first.setTextColor(this.getResources().getColor(R.color.home_default_text));
                tv_second.setTextColor(this.getResources().getColor(R.color.main_color));
                tv_third.setTextColor(this.getResources().getColor(R.color.home_default_text));
                if (secondFragment == null) {
                    secondFragment = new SecondFragment();
                    transaction.add(R.id.ll_ment_bottom, secondFragment);
                } else {
                    transaction.show(secondFragment);
                }
                rl_first.setEnabled(true);
                rl_second.setEnabled(false);
                rl_third.setEnabled(true);
                break;
            case R.id.rl_third:
                view_one.setVisibility(View.GONE);
                view_two.setVisibility(View.GONE);
                view_three.setVisibility(View.VISIBLE);
                tv_first.setTextColor(this.getResources().getColor(R.color.home_default_text));
                tv_second.setTextColor(this.getResources().getColor(R.color.home_default_text));
                tv_third.setTextColor(this.getResources().getColor(R.color.main_color));
                if (thirdFragment == null) {
                    thirdFragment = new ThirdFragment();
                    transaction.add(R.id.ll_ment_bottom, thirdFragment);
                } else {
                    transaction.show(thirdFragment);
                }
                rl_first.setEnabled(true);
                rl_second.setEnabled(true);
                rl_third.setEnabled(false);
                break;
        }
        transaction.commit();
    }
}

fragment_tab.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:orientation="horizontal">

    <RelativeLayout
        android:id="@+id/rl_first"
        android:layout_width="0dp"
        android:layout_height="50dp"
        android:layout_weight="1">

        <TextView
            android:id="@+id/tv_first"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="First"
            android:textColor="@color/main_color" />

        <View
            android:id="@+id/view_one"
            android:layout_width="15dp"
            android:layout_height="3dp"
            android:layout_below="@+id/tv_first"
            android:layout_centerInParent="true"
            android:layout_marginTop="10dp"
            android:background="@drawable/tab_button" />
    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/rl_second"
        android:layout_width="0dp"
        android:layout_height="50dp"
        android:layout_weight="1">

        <TextView
            android:id="@+id/tv_second"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="Second"
            android:textColor="@color/home_default_text" />

        <View
            android:id="@+id/view_two"
            android:layout_width="15dp"
            android:layout_height="3dp"
            android:layout_below="@+id/tv_second"
            android:layout_centerInParent="true"
            android:layout_marginTop="10dp"
            android:background="@drawable/tab_button"
            android:visibility="gone" />
    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/rl_third"
        android:layout_width="0dp"
        android:layout_height="50dp"
        android:layout_weight="1">

        <TextView
            android:id="@+id/tv_third"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="Third"
            android:textColor="@color/home_default_text" />

        <View
            android:id="@+id/view_three"
            android:layout_width="15dp"
            android:layout_height="3dp"
            android:layout_below="@+id/tv_third"
            android:layout_centerInParent="true"
            android:layout_marginTop="10dp"
            android:background="@drawable/tab_button"
            android:visibility="gone" />
    </RelativeLayout>
</LinearLayout>

总结

最后在自己相对应的fragment中调用接口就可以了