方法一：UILoader

• UILoader.java

package cool.hyz.xujiayi.views;

import android.annotation.SuppressLint;
import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

import cool.hyz.xujiayi.R;
import cool.hyz.xujiayi.base.BaseApplication;
import cool.hyz.xujiayi.components.LoopTextView;

/**
 * @author xujiayi
 * @date 2023/11/5
 * 我只是个自由的主！
 */
public abstract class UILoader extends FrameLayout {

    private static final String TAG = "UILoader";

    private View mLoadingView;
    private View mSuccessView;
    private View mNetworkErrorView;
    private View mEmptyView;

    public void setShow(boolean show) {
        isShow = show;
        updateLoadingLoopTextState();
    }

    private OnRetryClickListener mOnRetryClickListener = null;

    public enum UIStatus {
        LOADING, SUCCESS, NETWORK_ERROR, EMPTY, NONE
    }

    public UIStatus mCurrentUIStatus = UIStatus.NONE;

    public UILoader(@NonNull Context context) {
        super(context);
    }

    public UILoader(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public UILoader(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        //初始化View
        initView();
    }

    /**
     * 更新状态
     *
     * @param status UIStatus
     */
    public void updateUIStatus(UIStatus status) {
        mCurrentUIStatus = status;
        BaseApplication.getHandler().post(this::switchUIByCurrentStatus);
    }

    /**
     * 初始化
     */
    private void initView() {
        switchUIByCurrentStatus();
    }

    /**
     * 根据当前状态切换UI
     */
    private void switchUIByCurrentStatus() {

        //加载中
        if (mLoadingView == null) {
            mLoadingView = getLoadingView();
            addView(mLoadingView);
        }
        //根据状态设置是否可见
        mLoadingView.setVisibility(mCurrentUIStatus == UIStatus.LOADING ? VISIBLE : GONE);

        //成功
        if (mSuccessView == null) {
            mSuccessView = getSuccessView(this);

            if (mSuccessView.getParent() instanceof ViewGroup) {
                ((ViewGroup) mSuccessView.getParent()).removeView(mSuccessView);
            }
            addView(mSuccessView);
        }
        //根据状态设置是否可见
        mSuccessView.setVisibility(mCurrentUIStatus == UIStatus.SUCCESS ? VISIBLE : GONE);


        //网络不佳
        if (mNetworkErrorView == null) {
            mNetworkErrorView = getNetworkErrorView();

            addView(mNetworkErrorView);
        }
        //根据状态设置是否可见
        mNetworkErrorView.setVisibility(mCurrentUIStatus == UIStatus.NETWORK_ERROR ? VISIBLE : GONE);

        //数据为空
        if (mEmptyView == null) {
            mEmptyView = getEmptyView();

            addView(mEmptyView);
        }
        //根据状态设置是否可见
        mEmptyView.setVisibility(mCurrentUIStatus == UIStatus.EMPTY ? VISIBLE : GONE);
    }


    /**
     * 创建LoadingView
     *
     * @return View
     */
    private View getLoadingView() {
        View loading = LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_loading, 
        return loading;
    }

    /**
     * SuccessView
     *
     * @return View
     */
    public abstract View getSuccessView(ViewGroup container);

    /**
     * NetworkErrorView
     *
     * @return View
     */
    private View getNetworkErrorView() {
        View networkErrorView = LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_network_error, this, false);
        networkErrorView.setOnClickListener((view) -> {
            if (mOnRetryClickListener != null) {
                mOnRetryClickListener.onClickToRetry();
            }
        });
        return networkErrorView;
    }

    /**
     * EmptyView
     *
     * @return View
     */
    private View getEmptyView() {
        return LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_empty, this, false);
    }


    public void setOnRetryClickListener(OnRetryClickListener listener) {
        mOnRetryClickListener = listener;
    }

    /**
     * 点击重试接口
     */
    public interface OnRetryClickListener {
        void onClickToRetry();
    }
}

java

• ui_loader_loading.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/page_background"
    android:gravity="center"
    android:orientation="vertical">

    <ImageView
        android:src="@drawable/ic_loading"
        android:layout_width="50dp"
        android:layout_height="50dp" />

    <TextView
        android:id="@+id/loading_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:text="正在拼命加载中..." />


</LinearLayout>
xml

• ui_loader_network_error.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/page_background"
    android:gravity="center"
    android:orientation="vertical">

    <ImageView
        android:src="@drawable/ic_network_error"
        android:layout_width="50dp"
        android:layout_height="50dp" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:text="网络不佳...点击重试" />


</LinearLayout>
xml

• ui_loader_empty.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/page_background"
    android:gravity="center"
    android:orientation="vertical">

    <ImageView
        android:src="@drawable/ic_empty"
        android:layout_width="50dp"
        android:layout_height="50dp" />


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:text="数据不翼而飞..." />


</LinearLayout>
xml

• 使用

package cool.hyz.xujiayi.views.home;

import android.content.Intent;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.lifecycle.ViewModelProvider;

import java.util.List;

import cool.hyz.xujiayi.R;
import cool.hyz.xujiayi.base.BaseFragment;
import cool.hyz.xujiayi.views.UILoader;

/**
 * @author xujiayi
 * @date 2023/11/5
 * 我只是个自由的主！
 */
public class HomeFragment extends Fragment {

    public static final String TAG = "HomeFragment";

    private View mRoot;
    private HomeViewModel mHomeViewModel;
    private static UILoader sUILoader;

    public HomeFragment() {

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

        if (sUILoader != null) {
            return sUILoader;
        }

        sUILoader = new UILoader(requireContext()) {
            @Override
            public View getSuccessView(ViewGroup container) {
                return createSuccess(inflater, container);
            }
        };

        sUILoader.setOnRetryClickListener(() -> {
            //TODO:retry
        });

        return sUILoader;
    }

    /**
     * @param inflater  inflater
     * @param container container
     * @return View
     */
    @Override
    public View createSuccess(LayoutInflater inflater, ViewGroup container) {
        Log.d(TAG, "createSuccess: ...");
        mHomeViewModel = new ViewModelProvider(this).get(HomeViewModel.class);
        mRoot = inflater.inflate(R.layout.fragment_home, container, false);
        sUILoader.updateUIStatus(UILoader.UIStatus.SUCCESS);
        return mRoot;
    }

    @Override
    public void onResume() {
        super.onResume();
        sUILoader.updateUIStatus(UILoader.UIStatus.LOADING);
    }
}
java

方法二：BaseFragment

• BaseFragment.java

package cool.hyz.xujiayi.base;

import static android.view.View.GONE;
import static android.view.View.VISIBLE;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;

import cool.hyz.xujiayi.R;
import cool.hyz.xujiayi.components.LoopTextView;

public abstract class BaseFragment extends Fragment {

    public static final String TAG = "BaseFragment";

    private View mRoot;

    private FrameLayout mBaseContainer;

    private View mLoadingView;

    private View mSuccessView;

    private View mNetworkErrorView;

    private View mEmptyView;

    protected boolean isLoaded = false;

    private OnRetryClickListener mOnRetryClickListener = null;


    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        mRoot = inflater.inflate(R.layout.base_fragment_layout, container, false);
        mBaseContainer = mRoot.findViewById(R.id.base_container);
        loadStateView(inflater, container);
        return mRoot;
    }

    public enum UIStatus {
        LOADING, SUCCESS, NETWORK_ERROR, EMPTY, NONE
    }

    public UIStatus mCurrentUIStatus = UIStatus.NONE;

    /**
     * 加载View
     *
     * @param inflater  LayoutInflater
     * @param container ViewGroup
     */
    private void loadStateView(LayoutInflater inflater, ViewGroup container) {

        //1.加载中
        mLoadingView = createLoadingView(container);
        mBaseContainer.addView(mLoadingView);
        //根据状态设置是否可见
        mLoadingView.setVisibility(mCurrentUIStatus == UIStatus.LOADING ? VISIBLE : GONE);
        updateLoadingLoopTextState();

        //2.成功
        mSuccessView = createSuccessView(inflater, container);
        if (mSuccessView.getParent() instanceof ViewGroup) {
            ((ViewGroup) mSuccessView.getParent()).removeView(mSuccessView);
        }
        mBaseContainer.addView(mSuccessView);
        //根据状态设置是否可见
        mSuccessView.setVisibility(mCurrentUIStatus == UIStatus.SUCCESS ? VISIBLE : GONE);

        //3.网络不佳
        mNetworkErrorView = createNetworkErrorView(container);
        mBaseContainer.addView(mNetworkErrorView);
        //根据状态设置是否可见
        mNetworkErrorView.setVisibility(mCurrentUIStatus == UIStatus.NETWORK_ERROR ? VISIBLE : GONE);

        //4.数据为空
        mEmptyView = createEmptyView(container);
        mBaseContainer.addView(mEmptyView);
        //根据状态设置是否可见
        mEmptyView.setVisibility(mCurrentUIStatus == UIStatus.EMPTY ? VISIBLE : GONE);
    }

    /**
     * 更新状态
     *
     * @param status UIStatus
     */
    public void updateUIStatus(UIStatus status) {
        mCurrentUIStatus = status;

        //1.加载中，根据状态设置是否可见
        mLoadingView.setVisibility(mCurrentUIStatus == UIStatus.LOADING ? VISIBLE : GONE);
        updateLoadingLoopTextState();

        //2.成功，根据状态设置是否可见
        mSuccessView.setVisibility(mCurrentUIStatus == UIStatus.SUCCESS ? VISIBLE : GONE);

        //3.网络不佳，根据状态设置是否可见
        mNetworkErrorView.setVisibility(mCurrentUIStatus == UIStatus.NETWORK_ERROR ? VISIBLE : GONE);

        //4.数据为空，根据状态设置是否可见
        mEmptyView.setVisibility(mCurrentUIStatus == UIStatus.EMPTY ? VISIBLE : GONE);
    }

    private void updateLoadingLoopTextState() {
        if (mLoadingView != null) {
            LoopTextView loopTextView = mLoadingView.findViewById(R.id.loading_title);
            if (mCurrentUIStatus == UIStatus.LOADING && isShow) loopTextView.startLoop();
            else loopTextView.stopLoop();
        }
    }

    /**
     * 创建LoadingView
     *
     * @return View
     */
    private View createLoadingView(ViewGroup container) {
        View loading = LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_loading, container, false);
        return loading;
    }

    /**
     * SuccessView
     *
     * @return View
     */
    public abstract View createSuccessView(LayoutInflater inflater, ViewGroup container);

    /**
     * NetworkErrorView
     *
     * @return View
     */
    private View createNetworkErrorView(ViewGroup container) {
        View networkErrorView = LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_network_error, container, false);
        networkErrorView.setOnClickListener((view) -> {
            if (mOnRetryClickListener != null) {
                mOnRetryClickListener.onClickToRetry();
            }
        });
        return networkErrorView;
    }

    /**
     * EmptyView
     *
     * @return View
     */
    private View createEmptyView(ViewGroup container) {
        return LayoutInflater.from(getContext()).inflate(R.layout.ui_loader_empty, container, false);
    }


    /**
     * 设置listener
     *
     * @param listener OnRetryClickListener
     */
    public void setOnRetryClickListener(OnRetryClickListener listener) {
        mOnRetryClickListener = listener;
    }

    /**
     * 点击重试接口
     */
    public interface OnRetryClickListener {
        void onClickToRetry();
    }
}
java

• HomeFragment.java

package cool.hyz.xujiayi.views.home;

import android.content.Intent;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.lifecycle.ViewModelProvider;


import java.util.List;

import cool.hyz.xujiayi.R;
import cool.hyz.xujiayi.base.BaseFragment;

/**
 * @author xujiayi
 * @date 2023/11/5
 * 我只是个自由的主！
 */
public class HomeFragment extends BaseFragment{

    public static final String TAG = "HomeFragment";

    private View mRoot;
    private HomeViewModel mHomeViewModel;

    public HomeFragment() {

    }


    /**
     * 创建成功View
     * @param inflater LayoutInflater
     * @param container ViewGroup
     * @return View
     */
    @Override
    public View createSuccessView(LayoutInflater inflater, ViewGroup container) {
        Log.d(TAG, "createSuccessView: ...");
        mHomeViewModel = new ViewModelProvider(this).get(HomeViewModel.class);
        mRoot = inflater.inflate(R.layout.fragment_home, container, false);

        mHomeViewModel.loadData().observe(getViewLifecycleOwner(), this::setData);
        return mRoot;
    }

    private void setData(String data){
        Log.d(TAG, "setData: "+data);
        updateUIStatus(UIStatus.SUCCESS);
    }

}
java

• d

package cool.hyz.xujiayi.views.home;

import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.ViewModel;

import java.util.List;

public class HomeViewModel extends ViewModel {

    public HomeViewModel() {
    }


    /**
     * 加载成功
     */
    public LiveData<String> loadData(){
        MutableLiveData<String> data = new MutableLiveData<>();
        data.setValue("加载成功...");
        return data;
    }
}
java