Small white just to learn the basic knowledge of database, how to do it as video open the db files, without the data, a all have no, the great god, please answer, thank you,

 import android. The content. The Context; 
The import android. Database. Sqlite. SQLiteDatabase; 
The import android. Database. Sqlite. SQLiteOpenHelper; 

Public class NotesDB extends SQLiteOpenHelper {

Public static final String TABLE_NAME="notes"; 
Public static final String CONTENT="CONTENT"; 
Public static final String ID="_id"; 
Public static final String TIME="TIME"; 

Public NotesDB Context (Context) {
Super (context, "notes", null, 1); 
} 

@ Override 
Public void onCreate (SQLiteDatabase db) {
Db. ExecSQL (TABLE_NAME "CREATE TABLE" + + "(" + ID 
+ "INTEGER PRIMARY KEY AUTOINCREMENT," + CONTENT 
+ TEXT NOT NULL, "" + TIME +" TEXT NOT NULL) "); 
} 

@ Override 
Public void onUpgrade (SQLiteDatabase db, int oldVersion, int newVersion) {

} 
} 

This is the main activity

 
The import android. The Manifest; 
The import android. Content. ContentValues; 
The import android. Database. Sqlite. SQLiteDatabase; 
The import android. Support. V7. App. AppCompatActivity; 
The import android. OS. Bundle; 
import android.widget.TextView; 
The import android. Widget. Toast; 

The import com. Ysuper2009. Note. R; 
The import com. Ysuper2009. Note. Db. NotesDB; 
The import com. Ysuper2009. Note. Util. YPermissionManager; 

Import the Java. Text. SimpleDateFormat; 
Import the Java. Util. Date; 
import java.util.List; 

The import pub. Devrel. Easypermissions. AppSettingsDialog; 
The import pub. Devrel. Easypermissions. Easypermissions; 


Public class MainActivity extends AppCompatActivity {

Private String [] perms={Manifest. Permission. The CAMERA, the Manifest. Permission. WRITE_EXTERNAL_STORAGE}; 
private TextView tv; 
//database content 
Private NotesDB NotesDB; 
Private SQLiteDatabase dbWriter; 

@ Override 
Protected void onCreate (Bundle savedInstanceState) {
super.onCreate(savedInstanceState); 
The setContentView (R.l ayout. Activity_main); 
TV=(TextView) the findViewById (R.i which x); 


//YPermissionManager YPermissionManager=new YPermissionManager (); 
//yPermissionManager checkBasePermission (this, perms); 

NotesDB=new notesDB (this); 
DbWriter=notesDB. GetWritableDatabase (); 
The add (); 

} 

Public void the add () {
ContentValues CV=new ContentValues (); 
CV. Put (NotesDB. The CONTENT, "tongtong"); 
CV. Put (NotesDB. TIME, getTime ()); 
DbWriter. Insert (NotesDB TABLE_NAME, null, CV); 

} 

Public String getTime () {
SimpleDateFormat format=new SimpleDateFormat (" on dd MM yyyy years HH: MM: ss "); 
The Date curDate=new Date (); 
String STR=format. The format (curDate); 
TV. SetText (STR); 
return str; 
} 

/* 
@ Override 
Public void onRequestPermissionsResult (int requestCode, String [] permissions, int [] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults); 
EasyPermissions. OnRequestPermissionsResult (requestCode, permissions, grantResults); 
} 

@ Override 
Public void onPermissionsGranted (int requestCode List Perms) {
Toast. MakeText (this, "permission is ok, do use it," Toast. LENGTH_SHORT), show (); 
} 

@ Override 
Public void onPermissionsDenied (int requestCode List Perms) {
Toast. MakeText (this, "permission to fail", Toast. LENGTH_SHORT), show (); 
If (EasyPermissions. SomePermissionPermanentlyDenied (this, perms)) {
New AppSettingsDialog. Builder (this). The build (), show (); 
} 
} 

*/

} 

CodePudding user response:

As in the open plug-in is like this, without the data,

CodePudding user response:

Forgot to say, with MAC

CodePudding user response:

Online, etc.,,,,,,,,,,

CodePudding user response:

Don't seem to create success,,,

CodePudding user response:

Look at the data, and forgot to add the close, ha ha,

The

reference 4 floor gxh_apologize reply:

seems to be no create success,,,

CodePudding user response:

Suggest you learn androidx. Room. *, compared with the manual operation SQLite, developing more efficient,