[B4A] การเชื่อมต่อฐานข้อมูล MySQL ทั้งแบบ Local/Remote ผ่านทางการใช้งาน JDBC

thongkorn

สำหรับบทความชุดนี้เป็นการเชื่อมต่อฐานข้อมูล MySQL ทั้งแบบ Local/Remote ผ่านทาง JDBC เป็นการติดต่อโดยตรงเข้าสู่ฐานข้อมูลครับผม ...

ดาวน์โหลด B4A เพื่อติดตั้งใช้งานฟรี ...

ดาวน์โหลดโค้ดต้นฉบับสำหรับบทความชุดนี้ ...

ไฟล์ Libraries จะอยู่ใน Zip File เมื่อแตกออกมาให้คัดลอกไฟล์ทั้งหมดไปเก็บไว้ที่ C:\Program Files (x86)\Anywhere Software\Basic4android\Libraries ...


ไฟล์ Libraries ที่จำเป็นต้องใช้งาน ...


ใน phpMyAdmin สำหรับการ Import ไฟล์ SQL ตัวอย่างเข้ามา ...



ตารางข้อมูลตัวอย่าง ...


มาดูโค้ดกันเถอะ ... Starter.bas

1. #Region  Service Attributes
   
2.         #StartAtBoot: False
   
3.         #ExcludeFromLibrary: True
   
4. #End Region
   
5. 
   
6. Sub Process_Globals
   
7.         'These global variables will be declared once when the application starts.
   
8.         'These variables can be accessed from all modules.
   
9.         '// Remote MySQL Server
   
10.         Public mysql As JdbcSQL
    
11.         Public driver As String = "com.mysql.jdbc.Driver"
    
12.         '// Link to Remote MySQL/Table Name
    
13.         Public jdbcUrl As String = "jdbc:mysql://www.remotemysql.com/PgseQEAkdl?useSSL=false"
    
14.         Public Username As String = "USERNAME"
    
15.         Public Password As String = "PASSWORD"
    
16.         '// Localhost
    
17.         'Private jdbcUrl As String = "jdbc:mysql://192.168.1.11:3306/contact"
    
18.         'Private Username As String = "USERNAME"
    
19.         'Private Password As String = "PASSWORD"
    
20. End Sub
    
21. 
    
22. Sub Connect As ResumableSub
    
23.         mysql.InitializeAsync("mysql", driver, jdbcUrl, Username, Password)
    
24.         Wait For MySQL_Ready (Success As Boolean)
    
25.         If Success = False Then
    
26.                 Log("Check unfiltered logs for JDBC errors.")
    
27.         End If
    
28.         Return Success
    
29. End Sub
    
30. 
    
31. Sub CloseConnection
    
32.         mysql.Close
    
33. End Sub
    
34. 
    
35. Sub DisableStrictMode
    
36.         Dim jo As JavaObject
    
37.         jo.InitializeStatic("android.os.Build.VERSION")
    
38.         If jo.GetField("SDK_INT") > 9 Then
    
39.                 Dim policy As JavaObject
    
40.                 policy = policy.InitializeNewInstance("android.os.StrictMode.ThreadPolicy.Builder", Null)
    
41.                 policy = policy.RunMethodJO("permitAll", Null).RunMethodJO("build", Null)
    
42.                 Dim sm As JavaObject
    
43.                 sm.InitializeStatic("android.os.StrictMode").RunMethod("setThreadPolicy", Array(policy))
    
44.         End If
    
45. End Sub
    
46. 
    
47. Sub Service_Create
    
48.         'This is the program entry point.
    
49.         'This is a good place to load resources that are not specific to a single activity.
    
50.         'need to disable it as reading from large JdbcResultSet will cause network requests to be sent on the main thread.
    
51.         DisableStrictMode
    
52. End Sub
    
53. 
    
54. Sub Service_Start (StartingIntent As Intent)
    
55.         Service.StopAutomaticForeground 'Starter service can start in the foreground state in some edge cases.
    
56. End Sub
    
57. 
    
58. Sub Service_TaskRemoved
    
59.         'This event will be raised when the user removes the app from the recent apps list.
    
60. End Sub
    
61. 
    
62. 'Return true to allow the OS default exceptions handler to handle the uncaught exception.
    
63. Sub Application_Error (Error As Exception, StackTrace As String) As Boolean
    
64.         Return True
    
65. End Sub
    
66. 
    
67. Sub Service_Destroy
    
68. 
    
69. End Sub

คัดลอกไปที่คลิปบอร์ด

โค้ดในส่วนของ Main ...

1. #Region  Project Attributes
   
2.         #ApplicationLabel: Connect Remote MySQL
   
3.         #VersionCode: 1
   
4.         #VersionName:
   
5.         'SupportedOrientations possible values: unspecified, landscape or portrait.
   
6.         #SupportedOrientations: unspecified
   
7.         #CanInstallToExternalStorage: False
   
8. #End Region
   
9. 
   
10. #Region  Activity Attributes
    
11.         #FullScreen: False
    
12.         #IncludeTitle: True
    
13.     'MySQL Connector/J Driver
    
14.     #AdditionalJar: mysql-connector-java-5.1.47-bin.jar
    
15.         '#AdditionalJar: mysql-connector-java-5.1.34-bin
    
16.         '#AdditionalJar: mysql-connector-java-5.1.49-bin.jar
    
17.         #BridgeLogger: true
    
18. #End Region
    
19. 
    
20. '// https://www.b4x.com/android/help/jdbcsql.html
    
21. Sub Process_Globals
    
22.         'These global variables will be declared once when the application starts.
    
23.         'These variables can be accessed from all modules.
    
24. End Sub
    
25. 
    
26. Sub Globals
    
27.         'These global variables will be redeclared each time the activity is created.
    
28.         'These variables can only be accessed from this module.
    
29.         Private Kanit As CustomFonts
    
30.         Private ListView1 As ListView
    
31.         Private ProgressBar1 As ProgressBar
    
32. End Sub
    
33. 
    
34. 
    
35. Sub Activity_Create(FirstTime As Boolean)
    
36.         Activity.LoadLayout("main")
    
37.         Activity.Title="Connect Remote MySQL [JDBC]"
    
38.         '// Set Own Font.
    
39.         Kanit.Initialize("Kanit-Regular.ttf")
    
40.         Kanit.SetCustomFontsToAllViews(Activity)
    
41.         '// Initialized.
    
42.         ProgressBar1.Visible = True
    
43.         Wait For (Starter.Connect) Complete (Success As Boolean)
    
44.         'Log(Success)
    
45.         If Success Then
    
46.                 Dim jsql As JdbcResultSet
    
47.                 Starter.mysql.Initialize2(Starter.driver, Starter.jdbcUrl, Starter.Username, Starter.Password)
    
48.                 '/ Localhost Query
    
49.                 '/jsql=Starter.mysql.ExecQuery("SELECT ContactPK, ContactID, FullName FROM contact.tblcontact ")
    
50.                 jsql = Starter.mysql.ExecQuery("SELECT ContactPK, ContactID, FullName FROM tblcontact ORDER BY ContactID")
    
51.                 Do While jsql.NextRow
    
52.                         'Log(jsql.GetString("ContactID"))
    
53.                         ListView1.AddTwoLines2(jsql.GetString("ContactID"), jsql.GetString("Fullname"), jsql.GetString("ContactPK"))
    
54.                 Loop
    
55.                 Starter.CloseConnection
    
56.         End If
    
57.         ProgressBar1.Visible = False
    
58. End Sub
    
59.        
    
60. Sub Activity_Resume
    
61. 
    
62. End Sub
    
63. 
    
64. Sub Activity_Pause (UserClosed As Boolean)
    
65. 
    
66. End Sub

คัดลอกไปที่คลิปบอร์ด