我正在了解适用于 Android 应用程序的 CouchBase Lite，目前我只知道如何创建管理器、数据库、文档和 View 。但是我想从文档加载数据并将其显示在应用程序中但是在尝试了几次并遵循了一些教程之后失败了。有没有一种方法可以保存和加载这些数据并在 Listview 中对其进行操作？我现在使用的代码如下:
public class MainActivity extends AppCompatActivity {
final String dbname = "userdils";
private String docId = "2";
private Manager manager;
private Database couchDb;
private TextView tvLogWindow;
private EditText u_id;
private EditText pwd;
Button btn_login,btn_login1;
TextView version;
private String TAG = "CouchBaseLiteLoginPage";
String email;
String password;
private UserDetails ud,udd;
private ArrayList<UserDetails> ud1;
String doc_id;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//tvLogWindow = (TextView) findViewById(R.id.tv_log_window);
u_id = (EditText) findViewById(R.id.user_id);
pwd = (EditText) findViewById(R.id.password);
btn_login = (Button) findViewById(R.id.btn_login);
btn_login1 = (Button) findViewById(R.id.btn_login1);
/*tvLogWindow.setText(tvLogWindow.getText().toString() + "\n\nStart Couchbase App!");
if (!Manager.isValidDatabaseName(dbname)) {
tvLogWindow.setText(tvLogWindow.getText().toString() + "\n\nBad couchbase db name!");
return;
}*/
createManager();
createCouchdb();
btn_login.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v)
{
Log.d(TAG, "Create: " + 1);
login();
}
});
btn_login1.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v)
{
Log.d(TAG, "View: " + 2);
docView();
// retrieveMovie(manager,couchDb,docId);
}
});
//createDocument(docId);
//Document retrievedDocument = retrieveDocument();
/*updateDocument(retrievedDocument);
deleteDocument(retrievedDocument);*/
//tvLogWindow.setText(tvLogWindow.getText().toString() + "\n\nEnd the App!");
}
public void createManager() {
try {
manager = new Manager(new AndroidContext(getApplicationContext()), Manager.DEFAULT_OPTIONS);
} catch (IOException e) {
return;
}
}
public void createCouchdb() {
try {
couchDb = manager.getDatabase(dbname);
} catch (CouchbaseLiteException e) {
return;
}
}
public Document retrieveDocument(String docId) {
Document retrievedDocument = couchDb.getDocument(docId);
Log.d(TAG, "Retrieved Data:- " + String.valueOf(retrievedDocument.getProperties()));
// Let's find the documents that have conflicts so we can resolve them:
Query query = couchDb.createAllDocumentsQuery();
query.setAllDocsMode(Query.AllDocsMode.ALL_DOCS);
try {
QueryEnumerator result = query.run();
for (Iterator<QueryRow> it = result;
it.hasNext(); ) {
QueryRow row = it.next();
Object movieObj = row.getDocument().getProperties().get("user_det");
Gson gson = new Gson();
String jsonString = gson.toJson(movieObj, Map.class); //Convert the object to json string using Gson
UserDetails movie = gson.fromJson(jsonString, UserDetails.class); //convert the json string to Movie object
if(movie.getUser_pwd().equals("000000")) {
Log.i("getMovieFromDocument", "movie>>>" + movie.getUser_nm());
}
Log.d(TAG, "Document Data ID:- " + row.getDocumentId());
}
}
catch (CouchbaseLiteException e) {
}
// Log.d(TAG, "User Name:- " +(String)retrievedDocument.getProperty("user_det"));
return retrievedDocument;
}
public void login() {
Log.d(TAG, "validate: " + 4);
email = u_id.getText().toString().trim();
password = pwd.getText().toString().trim();
Log.d(TAG, "login: " + 5);
btn_login.setEnabled(false);
ud = new UserDetails();
udd = new UserDetails();
ud1 = new ArrayList<UserDetails>();
ud.setUser_nm(email);
ud.setUser_pwd(password);
udd.setUser_nm("NAME_007");
udd.setUser_pwd("PWD_007");
ud1.add(ud);
ud1.add(udd);
createDocument(docId,ud1);
}
public void createDocument(String docId,ArrayList<UserDetails> ud) {
// create some dummy data
SimpleDateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
Calendar calendar = GregorianCalendar.getInstance();
String currentTimeString = dateFormatter.format(calendar.getTime());
//Movie movie = new Movie("Star War", "The force awakens!", 120);
// put those dummy data together
Map<String, Object> docContent = new HashMap<String, Object>();
docContent.put("message", "Hey Couchbase Lite");
docContent.put("creationDate", currentTimeString);
docContent.put("user_det", ud);
//docContent.put("movie", movie);
Log.d(TAG, "userDetails: " + String.valueOf(docContent));
// create an empty document, add content and write it to the couchDb
//Document document = new Document(couchDb,docId);
//Document document = couchDb.createDocument();
Document document = new Document(couchDb,docId);
try {
document.putProperties(docContent);
//doc_id = document.getId();
// Document retrieveDoc = retrieveDocument(docId);
Log.d(TAG, "Document Count couchDb : " + couchDb.getDocumentCount());
} catch (CouchbaseLiteException e) {
}
}
public void docView() {
// Document retrievedDocument = retrieveDocument(docId);
Document retrievedDocument = retrieveDocument(docId);
}
private void retrieveMovie(Manager manager, Database couchDb, String docId) {
Document retrievedDocument = couchDb.getDocument(docId); // Retrieve the document by id
Object movieObj = retrievedDocument.getProperties().get("user_det");
Gson gson = new Gson();
String jsonString = gson.toJson(movieObj, Map.class); //Convert the object to json string using Gson
UserDetails movie = gson.fromJson(jsonString, UserDetails.class); //convert the json string to Movie object
Log.i("getMovieFromDocument", "jsonString>>>" + jsonString);
Log.i("getMovieFromDocument", "movie>>>" + movie.getUser_nm());
}
}
最佳答案
不清楚您遵循了哪些教程以及观察到了哪些错误。无论如何，看看这个 blog讨论了如何使用 Couchbase Lite 作为数据源在 RecyclerView 中加载文档。推荐的模式可以很容易地应用于 ListView 或只在您的应用中使用 RecyclerView 而不是 ListView。
关于android - 如何从 Couchbase 数据库中保存和获取数据并将其显示在 ListView 上？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/49715836/