package com
.liruijie
.dufucaotang;
import android
.os
.Bundle;
import android
.util
.Log;
import android
.view
.View;
import android
.widget
.ProgressBar;
import android
.widget
.Toast;
import androidx
.appcompat
.app
.AppCompatActivity;
import androidx
.recyclerview
.widget
.LinearLayoutManager;
import androidx
.recyclerview
.widget
.RecyclerView;
import com
.liruijie
.dufucaotang
.adapter
.NewsAdapter;
import com
.liruijie
.dufucaotang
.model
.News;
import com
.liruijie
.dufucaotang
.utils
.NewsApiUtils;
import java
.util
.List;
public class OverviewLatestNewsActivity extends AppCompatActivity {
private RecyclerView newsRecyclerView;
private NewsAdapter newsAdapter;
private ProgressBar progressBar;
private static final String TAG = "LatestNewsActivity";
@Override
protected void onCreate
(Bundle savedInstanceState
) {
super
.onCreate
(savedInstanceState
);
setContentView
(R
.layout
.activity_overview_latest_news
);
// 设置标题
if
(getSupportActionBar
() != null
) {
getSupportActionBar
().setTitle
("最新动态"
);
}
// 初始化视图
initViews
();
// 加载新闻数据
loadNewsData
();
}
/**
* 初始化视图组件
*/
private void initViews
() {
newsRecyclerView = findViewById
(R
.id
.news_recycler_view
);
progressBar = findViewById
(R
.id
.progress_bar
);
// 设置RecyclerView
newsRecyclerView
.setLayoutManager
(new LinearLayoutManager
(this
));
newsAdapter = new NewsAdapter
(this, null
);
newsRecyclerView
.setAdapter
(newsAdapter
);
}
/**
* 加载新闻数据
*/
private void
loadNewsData
() {
// 显示加载进度条
progressBar
.setVisibility
(View
.VISIBLE
);
// 使用新闻API工具类获取数据
NewsApiUtils
.getInstance
().getNewsList
(new NewsApiUtils
.NewsCallback
() {
@Override
public void onSuccess
(List<News> newsList
) {
// 在主线程更新UI
runOnUiThread
(() -> {
progressBar
.setVisibility
(View
.GONE
);
if
(newsList != null && !newsList
.isEmpty
()) {
// 显示新闻列表
newsAdapter
.setNewsList
(newsList
);
} else {
// 无新闻数据提示
Toast
.makeText
(OverviewLatestNewsActivity
.this,
"暂无最新动态", Toast
.LENGTH_SHORT
).show
();
}
}
);
}
@Override
public void onError
(String error
) {
// 在主线程处理错误
runOnUiThread
(() -> {
progressBar
.setVisibility
(View
.GONE
);
Log
.e
(TAG, "加载新闻失败: " + error
);
Toast
.makeText
(OverviewLatestNewsActivity
.this,
"加载新闻失败: " + error, Toast
.LENGTH_SHORT
).show
();
}
);
}
}
);
}
/**
* 销毁时的资源释放
*/
@Override
protected void onDestroy
() {
super
.onDestroy
();
// 可以在此处添加资源释放逻辑
}
}<?xml version="1
.0" encoding="utf-8"?>
<androidx
.core
.widget
.NestedScrollView 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">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="16dp">
<TextView
android:id="@+id/title_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="最新动态"
android:textSize="24sp"
android:textStyle="bold"
android:layout_marginBottom="16dp"/>
<TextView
android:id="@+id/intro_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="这里展示杜甫草堂的最新活动、展览和重要事件，欢迎关注我们的文化活动。"
android:textSize="16sp"
android:lineSpacingMultiplier="1
.2"
android:layout_marginBottom="24dp"/>
<!-- 加载进度条 -->
<ProgressBar
android:id="@+id/progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:visibility="gone"/>
<!-- 空数据提示 -->
<TextView
android:id="@+id/empty_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="暂无新闻数据"
android:textSize="18sp"
android:textColor="#888888"
android:gravity="center"
android:padding="24dp"
android:visibility="gone"/>
<!-- 新闻列表 - 使用RecyclerView实现动态加载 -->
<androidx
.recyclerview
.widget
.RecyclerView
android:id="@+id/news_recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_behavior="@string/appbar_scrolling_view_behavior"/>
</LinearLayout>
</androidx
.core
.widget
.NestedScrollView>package com
.liruijie
.dufucaotang;
import android
.content
.Context;
import android
.view
.LayoutInflater;
import android
.view
.View;
import android
.view
.ViewGroup;
import android
.widget
.ImageView;
import androidx
.annotation
.NonNull;
import androidx
.recyclerview
.widget
.RecyclerView;
import java
.util
.List;
public class ImageAdapter extends RecyclerView
.Adapter<ImageAdapter
.ImageViewHolder> {
private Context mContext;
private List<Integer> mImageList;
public ImageAdapter
(Context context, List<Integer> imageList
) {
mContext = context;
mImageList = imageList;
}
@NonNull
@Override
public ImageViewHolder onCreateViewHolder
(@NonNull ViewGroup parent, int viewType
) {
View view = LayoutInflater
.from
(mContext
).inflate
(R
.layout
.item_image, parent, false
);
return new ImageViewHolder
(view
);
}
@Override
public void onBindViewHolder
(@NonNull ImageViewHolder holder, int position
) {
int imageResId = mImageList
.get
(position % mImageList
.size
());
holder
.imageView
.setImageResource
(imageResId
);
}
@Override
public int getItemCount
() {
return Integer
.MAX_VALUE; // 实现无限循环
}
public static class ImageViewHolder extends RecyclerView
.ViewHolder {
ImageView imageView;
public ImageViewHolder
(@NonNull View itemView
) {
super
(itemView
);
imageView = itemView
.findViewById
(R
.id
.imageView
);
}
}
}package com
.liruijie
.dufucaotang
.utils;
import android
.util
.Log;
import com
.google
.gson
.Gson;
import com
.google
.gson
.reflect
.TypeToken;
import com
.liruijie
.dufucaotang
.model
.News;
import java
.io
.IOException;
import java
.util
.List;
import java
.util
.concurrent
.TimeUnit;
import okhttp3
.Call;
import okhttp3
.Callback;
import okhttp3
.OkHttpClient;
import okhttp3
.Request;
import okhttp3
.Response;
/**
* 新闻请求专用工具类
*/
public class NewsApiUtils {
private static final String TAG = "NewsApiUtils";
private static final String BASE_
URL = "http://10
.0
.2
.2:8080/api/";
// 单例模式
private static NewsApiUtils instance;
private final OkHttpClient client;
private final Gson gson;
private NewsApiUtils
() {
// 配置OkHttpClient
client = new OkHttpClient
.Builder
()
.connectTimeout
(15, TimeUnit
.SECONDS
)
.readTimeout
(15, TimeUnit
.SECONDS
)
.writeTimeout
(15, TimeUnit
.SECONDS
)
.build
();
// 初始化Gson
gson = new Gson
();
}
// 获取单例实例
public static NewsApiUtils getInstance
() {
if
(instance == null
) {
synchronized
(NewsApiUtils
.class
) {
if
(instance == null
) {
instance = new NewsApiUtils
();
}
}
}
return instance;
}
/**
* 获取新闻列表
* @param callback 回调接口
*/
public void getNewsList
(final NewsCallback callback
) {
String
url = BASE_
URL + "news";
Request request = new Request
.Builder
()
.url(url)
.get
()
.build
();
client
.newCall
(request
).enqueue
(new Callback
() {
@Override
public void onFailure
(Call call, IOException e
) {
Log
.e
(TAG, "获取新闻失败: " + e
.getMessage
());
if
(callback != null
) {
callback
.onError
("网络错误: " + e
.getMessage
());
}
}
@Override
public void onResponse
(Call call, Response response
) throws IOException {
try {
if
(response
.isSuccessful
() && response
.body
() != null
) {
String json = response
.body
().string
();
// 解析JSON数据
TypeToken<List<News>> typeToken = new TypeToken<List<News>>
() {};
List<News> newsList = gson
.fromJson
(json, typeToken
.getType
());
if
(callback != null
) {
callback
.onSuccess
(newsList
);
}
} else {
if
(callback != null
) {
callback
.onError
("请求失败: " + response
.code
());
}
}
} catch
(Exception e
) {
Log
.e
(TAG, "解析新闻数据失败: " + e
.getMessage
());
if
(callback != null
) {
callback
.onError
("解析数据失败: " + e
.getMessage
());
}
} finally {
response
.close
();
}
}
}
);
}
/**
* 根据ID获取单条新闻
* @param newsId 新闻ID
* @param callback 回调接口
*/
public void getNewsById
(int newsId, final NewsItemCallback callback
) {
String
url = BASE_
URL + "news/" + newsId;
Request request = new Request
.Builder
()
.url(url)
.get
()
.build
();
client
.newCall
(request
).enqueue
(new Callback
() {
@Override
public void onFailure
(Call call, IOException e
) {
Log
.e
(TAG, "获取单条新闻失败: " + e
.getMessage
());
if
(callback != null
) {
callback
.onError
("网络错误: " + e
.getMessage
());
}
}
@Override
public void onResponse
(Call call, Response response
) throws IOException {
try {
if
(response
.isSuccessful
() && response
.body
() != null
) {
String json = response
.body
().string
();
// 解析JSON数据
News news = gson
.fromJson
(json, News
.class
);
if
(callback != null
) {
callback
.onSuccess
(news
);
}
} else {
if
(callback != null
) {
callback
.onError
("请求失败: " + response
.code
());
}
}
} catch
(Exception e
) {
Log
.e
(TAG, "解析单条新闻数据失败: " + e
.getMessage
());
if
(callback != null
) {
callback
.onError
("解析数据失败: " + e
.getMessage
());
}
} finally {
response
.close
();
}
}
}
);
}
// 新闻列表回调接口
public interface NewsCallback {
void onSuccess
(List<News> newsList
);
void onError
(String error
);
}
// 单条新闻回调接口
public interface NewsItemCallback {
void onSuccess
(News news
);
void onError
(String error
);
}
}package com
.liruijie
.dufucaotang
.adapter;
import android
.content
.Context;
import android
.util
.Log;
import android
.view
.LayoutInflater;
import android
.view
.View;
import android
.view
.ViewGroup;
import android
.widget
.ImageView;
import android
.widget
.TextView;
import androidx
.annotation
.NonNull;
import androidx
.recyclerview
.widget
.RecyclerView;
import com
.liruijie
.dufucaotang
.R;
import com
.liruijie
.dufucaotang
.model
.News;
import java
.util
.List;
public class NewsAdapter extends RecyclerView
.Adapter<NewsAdapter
.NewsViewHolder> {
private Context context;
private List<News> newsList;
private OnItemClickListener listener;
public NewsAdapter
(Context context, List<News> newsList
) {
this
.context = context;
this
.newsList = newsList;
}
public void setNewsList
(List<News> newsList
) {
this
.newsList = newsList;
notifyDataSetChanged
();
}
public void setOnItemClickListener
(OnItemClickListener listener
) {
this
.listener = listener;
}
@NonNull
@Override
public NewsViewHolder onCreateViewHolder
(@NonNull ViewGroup parent, int viewType
) {
View view = LayoutInflater
.from
(context
).inflate
(R
.layout
.item_news, parent, false
);
return new NewsViewHolder
(view
);
}
@Override
public void onBindViewHolder
(@NonNull NewsViewHolder holder, int position
) {
News news = newsList
.get
(position
);
// 绑定文本数据
holder
.titleTextView
.setText
(news
.getTitle
());
holder
.dateTextView
.setText
(news
.getFormattedDate
());
holder
.contentTextView
.setText
(news
.getContent
());
// 加载本地图片
loadLocalImage
(news
.getImagePath
(), holder
.imageView
);
// 设置点击事件
holder
.itemView
.setOnClickListener
(v -> {
if
(listener != null
) {
listener
.onItemClick
(news
);
}
}
);
}
@Override
public int getItemCount
() {
return newsList != null ? newsList
.size
() : 0;
}
/**
* 从本地资源加载图片
*/
private void
loadLocalImage
(String imageName, ImageView imageView
) {
if
(imageName == null || imageName
.isEmpty
()) {
imageView
.setImageResource
(R
.drawable
.ic_error
);
Log
.w
("NewsAdapter", "图片名称为空"
);
return;
}
Log
.d
("NewsAdapter", "尝试加载图片: " + imageName
);
Log
.d
("NewsAdapter", "应用包名: " + context
.getPackageName
());
int resId = context
.getResources
().getIdentifier
(
imageName,
"drawable",
context
.getPackageName
()
);
if
(resId != 0
) {
imageView
.setImageResource
(resId
);
Log
.d
("NewsAdapter", "图片加载成功，资源ID: " + resId
);
} else {
imageView
.setImageResource
(R
.drawable
.ic_error
);
Log
.e
("NewsAdapter", "资源未找到! 请检查: " +
"1
. 图片文件是否在res/drawable目录下 " +
"2
. 文件名是否为" + imageName + "
.* " +
"3
. 文件名是否只包含小写字母、数字和下划线"
);
}
}
static class NewsViewHolder extends RecyclerView
.ViewHolder {
TextView titleTextView;
TextView dateTextView;
TextView contentTextView;
ImageView imageView;
public NewsViewHolder
(@NonNull View itemView
) {
super
(itemView
);
titleTextView = itemView
.findViewById
(R
.id
.news_title
);
dateTextView = itemView
.findViewById
(R
.id
.news_date
);
contentTextView = itemView
.findViewById
(R
.id
.news_content
);
imageView = itemView
.findViewById
(R
.id
.news_image
);
}
}
public interface OnItemClickListener {
void onItemClick
(News news
);
}
}mysql数据库保存的图片名字为calligraphy_exhibition，app还是查不出来，数据库已经成功连接
本文介绍了一种使用jQuery的.load()方法从服务器动态加载新闻内容到网页指定元素的方法。通过一个简单的实例展示了如何实现这一功能。
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