HarmonyOS 分布式聊天室应用程序

import com.ldd.myapp.bean.ChatDataBean; import com.ldd.myapp.provider.ChatProvider; import com.ldd.myapp.util.Tools; import ohos.aafwk.ability.AbilitySlice; import ohos.aafwk.content.Intent; import ohos.agp.components.Button; import ohos.agp.components.ListContainer; import ohos.agp.components.TextField; import ohos.app.Context; import ohos.bundle.IBundleManager; import ohos.data.distributed.common.*; import ohos.data.distributed.user.SingleKvStore; import ohos.utils.zson.ZSONArray; import ohos.utils.zson.ZSONObject; import java.util.ArrayList; import java.util.List; import static ohos.security.SystemPermission.DISTRIBUTED_DATASYNC; /** * 主页 */ public class MainAbilitySlice extends AbilitySlice { private Context mContext; // 聊天列表 private ListContainer lcList; // 聊天数据 private final List<ChatDataBean> listData = new ArrayList<>(); // 聊天数据适配器 private ChatProvider chatProvider; // 输入框 private TextField tfContent; // 发送按钮 private Button btnSend; // 分布式数据库管理器 private KvManager kvManager; // 分布式数据库 private SingleKvStore singleKvStore; // 数据库名称 private static final String STORE_NAME = "ChatStore"; // 存入的列表数据key private static final String KEY_DATA = "key_data"; // 存入的头像索引 private static final String KEY_PIC_INDEX = "key_pic_index"; private int picIndex = 0; @Override public void onStart(Intent intent) { super.onStart(intent); super.setUIContent(ResourceTable.Layout_ability_main); mContext = this; requestPermission(); initComponent(); initDatabase(); } /** * 请求分布式权限 */ private void requestPermission() { if (verifySelfPermission(DISTRIBUTED_DATASYNC) != IBundleManager.PERMISSION_GRANTED) { if (canRequestPermission(DISTRIBUTED_DATASYNC)) { requestPermissionsFromUser(new String[]{DISTRIBUTED_DATASYNC}, 0); } } } /** * 初始化组件 */ private void initComponent() { lcList = (ListContainer) findComponentById(ResourceTable.Id_lc_list); tfContent = (TextField) findComponentById(ResourceTable.Id_tf_content); tfContent.setAdjustInputPanel(true); btnSend = (Button) findComponentById(ResourceTable.Id_btn_send); btnSend.setEnabled(false); // 初始化适配器 chatProvider = new ChatProvider(mContext, listData); lcList.setItemProvider(chatProvider); // 输入框内容变化监听 tfContent.addTextObserver((text, start, before, count) -> { btnSend.setEnabled(text.length() != 0); }); // 点击发送按钮 btnSend.setClickedListener(component -> { String content = tfContent.getText().trim(); listData.add(new ChatDataBean(Tools.getDeviceId(mContext),picIndex,content)); // 存入数据库中 singleKvStore.putString(KEY_DATA, ZSONObject.toZSONString(listData)); // 清空输入框 tfContent.setText(""); }); } /** * 初始化分布式数据库 */ private void initDatabase() { // 创建分布式数据库管理器 kvManager = KvManagerFactory.getInstance().createKvManager(new KvManagerConfig(this)); // 数据库配置 Options options = new Options(); options.setCreateIfMissing(true) // 设置数据库不存在时是否创建 .setEncrypt(false) // 设置数据库是否加密 .setKvStoreType(KvStoreType.SINGLE_VERSION); //数据库类型 // 创建分布式数据库 singleKvStore = kvManager.getKvStore(options, STORE_NAME); // 监听数据库数据改变 singleKvStore.subscribe(SubscribeType.SUBSCRIBE_TYPE_ALL, new KvStoreObserver() { @Override public void onChange(ChangeNotification changeNotification) { List<Entry> insertEntries = changeNotification.getInsertEntries(); List<Entry> updateEntries = changeNotification.getUpdateEntries(); // 第一次存入数据，获取insertEntries if(insertEntries.size()>0){ for (Entry entry : insertEntries) { if (KEY_DATA.equals(entry.getKey())) { // 回调为非UI线程，需要在UI线程更新UI getUITaskDispatcher().syncDispatch(() -> { listData.clear(); listData.addAll(ZSONArray.stringToClassList(entry.getValue().getString(),ChatDataBean.class)); chatProvider.notifyDataChanged(); lcList.scrollTo(listData.size() - 1); }); } } }else if(updateEntries.size()>0){ for (Entry entry : updateEntries) { if (KEY_DATA.equals(entry.getKey())) { // 回调为非UI线程，需要在UI线程更新UI getUITaskDispatcher().syncDispatch(() -> { listData.clear(); listData.addAll(ZSONArray.stringToClassList(entry.getValue().getString(),ChatDataBean.class)); chatProvider.notifyDataChanged(); lcList.scrollTo(listData.size() - 1); }); } } } } }); try { picIndex = singleKvStore.getInt(KEY_PIC_INDEX); singleKvStore.putInt(KEY_PIC_INDEX, picIndex + 1); } catch (KvStoreException e) { e.printStackTrace(); // 没有找到，首次进入 if (e.getKvStoreErrorCode() == KvStoreErrorCode.KEY_NOT_FOUND) { picIndex = 0; singleKvStore.putInt(KEY_PIC_INDEX, picIndex + 1); } } } @Override protected void onStop() { super.onStop(); kvManager.closeKvStore(singleKvStore); } }