Computer Program

2008-11-16T05:14:00.000-08:00

Computer programs (also software programs, or just programs) are instructions for a computer.^[1] A computer requires programs to function. Moreover, a computer program does not run unless its instructions are executed by a central processor;^[2] however, a program may communicate an algorithm to people without running. Computer programs are usually executable programs or the source code from which executable programs are derived (e.g., compiled).

Computer source code is often written by professional computer programmers. Source code is written in a programming language that usually follows one of two main paradigms: imperative or declarative programming. Source code may be converted into an executable file (sometimes called an executable program or a binary) by a compiler. Alternatively, computer programs may be executed by a central processing unit with the aid of an interpreter, or may be embedded directly into hardware.

Computer programs may be categorized along functional lines: system software and application software. And many computer programs may run simultaneously on a single computer, a process known as multitasking.

Introduction Structure Data with C + +

2008-11-13T01:26:00.000-08:00

Data structure is one of the fundamental knowledge to learn programming, if you want to deepen more about the programming world, we must recognize from the requirements - in terms of creating the program. Here I will give an introduction of a data structure:
Function
Useful function to collect the statement, which can run into a block and run it back only by the name of the function of intermediate. Many functions are also used to accommodate the lines that are often used in a program.
Declare functions can be done in two ways, namely:
~ Header function without parameters
typeData namaFungsi ()
Example:
Int JumlahIsi ()
Double Random ()
Char * Name

Writing header function without parameters begins with a data type and followed by the name of the function, open parenthesis, brackets and close ('()'). If the function does not return value, the type of data used is void.
~ Header function with parameters
typeData namaFungsi ()
Example:
THE int (int a, int b)
Double ArcCon (double x)
Void List (int n, char * header)

Writing header function with nearly the same parameters with the function without parameters, which begins with the type of data, and the name and function followed by the parameters of each separated by commas with type.
Formal parameters and the Actual
If you have a function of the parameters that are in parenthesis (), parameters such as the formal parameters, while there are parameters on the command line caller function as the Actual parameter.
Transfer Parameters
When we call a function with parameters, there have been actual delivery of the parameters of the actual parameters to the formal parameters. Delivery of these parameters can be done in two ways:
Transfer the parameters by value (the value)
The value stored in the parameter sent to the function to be processed, but the results are not asked to be returned. In this mode, the flow direction 1, the caller from the procedure to procedure.
Transfer the parameters by location / reference (the reference)
Transfer the parameters by location often also known as the transfer of parameters by reference. In this case, the only location transferred only to be processed, and the results are returned and stored in a location that has been transferred it. In this mode, can occur 2-way flow of the caller function to function and sebalikya.
Recursive Function
This function to call himself, has used because of advantages, namely the writing line programs can be more brief. However, this function also has shortcomings, which require more memory because each time the program called by himself, needed some additional memory space.
Reference information can be retrieved from the books be by "Dwi Sanjaya"

Program Multimedia

2008-11-13T00:18:00.000-08:00

Program Multimedia
In the first discussion of this, I will give you the tricks how to create a multimedia applications or programs such as Winamp, which is able to run the mp3 files। To make this program we do not use the components of Windows Media Player version does not। In creating this program, the software we use Visual Basic 2005.

The ability of this program are:
a.Ikon program into the systray, not to the taskbar. So, we raise the window with this program and choose the menu icon in the systray this program.
b.Kita can adjust the volume difference between right and left speakers, can memute.
c.Terdapat sequence of songs (mp3)
d.Lagu can be selected in the folder you
e।Informasi name of the song can be displayed in animation.

File Class Module clsAudio

Enter the code Region Declaration of variables and functions of the Windows API such as the following:
Private Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Integer, ByVal hwndCallback As Integer) As Integer

Private _Filename As String = Nothing

Private _volLevel As Integer = Nothing

Private _muteOutput As Boolean = False

Private _rChanValue As Boolean = False

Private _lChanValue As Boolean = False

Private _rChanVol As Integer = Nothing

Private _lChanVol As Integer = Nothing

Private _playSpeed As Integer = Nothing

Private WithEvents waktu As New Timer
Declare a local (Private) use the Windows API mciSendString. Useless to send commands to the audio devices to run and certain audio files.
Pendeklarasian variable _filename local and general nature, useful for collecting data address audio files that run.
_volLevel Recognized variables that are useful to accommodate the large volume of audio used.
_muteOutput Recognized variables that are useful to accommodate speakers in the overall sound is muted or not.
_iChanValue Recognized variables that are useful for collecting the data is sound speakers left in muted or not.
_ChanVol Recognized variables that are useful to accommodate the large volume of data right speakers.
_iChanVol Recognized variables that are useful to accommodate the large volume of data speakers left.
_playSpeed Recognized variables that are useful to accommodate the data speed of sound, which is run.
Pendeklarasian the use of variable time as the control timer event along with it.
Code is included in the regional event are:
Public Event Playing()

Public Event Berhenti()

Public Event Kesalahan(ByVal info As String)

To set the event and class modules, the Public Event followed by the name of the event we want. If you want to generate Event is in a class module in the procedur we used the name RaiseEvent and followed that ditimbulkannya Event.
The code that we want to enter the region included in the next, the key region:
#Region "Tombol"

Public Sub PlayAudio()

Try

mciSendString("close song", 0, 0, 0)

mciSendString("open " & filename & " alias song", 0, 0, 0)

mciSendString("play song", 0, 0, 0)

waktu.Enabled = True

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

Public Sub StopAudio()

Try

mciSendString("stop song", 0, 0, 0)

waktu.Enabled = False

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

Public Sub PauseAudio()

Try

mciSendString("pause song", 0, 0, 0)

waktu.Enabled = False

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

Public Sub ResumeAudio()

Try

mciSendString("resume song", 0, 0, 0)

waktu.Enabled = True

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

Public Sub CloseAudio()

Try

mciSendString("close all", 0, 0, 0)

waktu.Enabled = False

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

#End Region
Code that is inserted in the region and InfoDurasi Position is:

Public ReadOnly Property PosisiInSec() As Integer

Get

Dim stat As String = Space(128)

mciSendString("set song time format milliseconds", 0, 0, 0)

mciSendString("status song position", stat, 128, 0)

Return Val(stat) / 1000

stat = Nothing

End Get

End Property

Public ReadOnly Property DurasiInSec() As Integer

Get

Dim totalTime As String = Space(128)

mciSendString("status song length", totalTime, 128, 0&)

Return Val(totalTime) / 1000

totalTime = Nothing

End Get

End Property

Public ReadOnly Property SisaWaktuInSec() As Integer

Get

Return (DurasiInSec - PosisiInSec)

End Get

End Property

Public ReadOnly Property formatPosisi() As String

Get

Dim sec As Integer = Val(PosisiInSec())

If sec < style="color: blue;">Then

Return "0:" & Format(sec, "00")

Else

Dim mins As Integer = Int(sec / 60)

sec = sec - (mins * 60)

Return Format(mins, "0") & ":" & Format(sec, "00")

End If

End Get

End Property

Public ReadOnly Property formatDurasi() As String

Get

Dim stat As String = Space(128)

mciSendString("set song time format ms", stat, 128, 0)

mciSendString("status song length", stat, 128, 0)

Return getThisTime(Val(stat))

End Get

End Property

Public ReadOnly Property formatSisaWaktu() As String

Get

Return getThisTime(SisaWaktuInSec * 1000)

End Get

End Property

Private Function getThisTime(ByVal timein As Integer) As String

Try

Dim remTime As Integer = timein / 1000

Dim conH As Integer = Int(remTime / 3600)

remTime = remTime Mod 3600

Dim conM As Integer = Int(remTime / 60)

remTime = remTime Mod 60

Dim conS As Integer = remTime

Dim strRetTime As String

If conH > 0 Then

strRetTime = Trim(Str(conH)) & ":"

Else

strRetTime = ""

End If

If conM >= 10 Then

strRetTime = strRetTime & Trim(Str(conM))

ElseIf conM > 0 Then

strRetTime = strRetTime & Trim(Str(conM))

Else

strRetTime = strRetTime & "0"

End If

strRetTime = strRetTime & ":"

If conS >= 10 Then

strRetTime = strRetTime & Trim(Str(conS))

ElseIf conS > 0 Then

strRetTime = strRetTime & "0" & Trim(Str(conS))

Else

strRetTime = strRetTime & "00"

End If

Return strRetTime

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

Return Nothing

End Try

End Function

In this region we make the properties - properties of the object to provide information about the way the audio files.

Code is included in the regional Audio Volume is:

Public Property volumeLevel() As Integer

Get

Dim theLevel As String = Space(128)

mciSendString("status song volume", theLevel, 128, 0)

_volLevel = Val(theLevel)

Return _volLevel

theLevel = Nothing

_volLevel = Nothing

End Get

Set(ByVal Value As Integer)

mciSendString("setaudio song volume to " & Value, 0, 0, 0)

End Set

End Property

Public Property muteSoundOutput() As Boolean

Get

muteSoundOutput = _muteOutput

End Get

Set(ByVal Value As Boolean)

If Value = True Then

mciSendString("set song audio all off", 0, 0, 0)

_muteOutput = Value

Else

mciSendString("set song audio all on", 0, 0, 0)

_muteOutput = Value

End If

End Set

End Property

Public Property rightChannelMute() As Boolean

Get

rightChannelMute = _rChanValue

End Get

Set(ByVal Value As Boolean)

If Value = True Then

mciSendString("setaudio song right off", 0, 0, 0)

_rChanValue = Value

Else

mciSendString("setaudio song right on", 0, 0, 0)

_rChanValue = Value

End If

End Set

End Property

Public Property leftChannelMute() As Boolean

Get

leftChannelMute = _lChanValue

End Get

Set(ByVal Value As Boolean)

If Value = True Then

mciSendString("setaudio song left off", 0, 0, 0)

_lChanValue = Value 'True

Else

mciSendString("setaudio song left on", 0, 0, 0)

_lChanValue = Value 'False

End If

End Set

End Property

Public Property leftVolume() As Integer

Get

Dim leftLevel As String = Space(128)

mciSendString("status song left volume", leftLevel, 128, 0)

_lChanVol = Val(leftLevel)

leftVolume = _lChanVol

leftLevel = Nothing

_lChanVol = Nothing

End Get

Set(ByVal Value As Integer)

mciSendString("setaudio song left volume to " & Value, 0, 0, 0)

End Set

End Property

Public Property rightVolume() As Integer

Get

Dim rightlevel As String = Space(128)

mciSendString("status song right volume", rightlevel, 128, 0)

_rChanVol = Val(rightlevel)

rightVolume = _rChanVol

rightlevel = Nothing

_rChanVol = Nothing

End Get

Set(ByVal Value As Integer)

mciSendString("setaudio song right volume to " & Value, 0, 0, 0)

End Set

End Property

Created a new property called volumelabel useful to get the volume level and set the volume of songs.
Code in the region other is the code that can not be included in the group above. Codes are:

Public Property filename() As String

Get

Return _Filename

'waktu.Enabled = True

End Get

Set(ByVal Value As String)

_Filename = Chr(34) + Trim(Value) + Chr(34)

End Set

End Property

Public ReadOnly Property deviceName() As String

Get

Dim theData As String = Space(128)

mciSendString("sysinfo song installname", theData, 128, 0)

Return theData

End Get

End Property

Public ReadOnly Property isPlaying() As Boolean

Get

Dim stat As String = Space(7)

mciSendString("status song mode", stat, 128, 0)

If stat = "playing" Then

Return True

waktu.Enabled = True

Else

Return False

End If

End Get

End Property

Public Property AturKecepatan() As Integer

Get

Dim rate As String = Space(128)

mciSendString("status song speed", rate, 128, 0)

_playSpeed = Val(rate)

Return _playSpeed

End Get

Set(ByVal Value As Integer)

mciSendString("set song speed " & Value, "", 0, 0)

End Set

End Property

Public Sub RubahPosisi(ByVal theSecond As Integer)

Try

theSecond = theSecond * 1000

If isPlaying = True Then mciSendString("play song from " & theSecond, 0, 0, 0)

If isPlaying = False Then mciSendString("seek song to " & theSecond, 0, 0, 0)

Catch exc As Exception

RaiseEvent Kesalahan(exc.Message)

End Try

End Sub

Private Sub waktu_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles waktu.Tick

If isPlaying = True Then

RaiseEvent Playing()

Else

RaiseEvent Berhenti()

waktu.Enabled = False

End If

End Sub

Protected Overrides Sub Finalize()

MyBase.Finalize()

End Sub

Public Sub New()

MyBase.New()

End Sub

End Class

* File Form frmMusik

The appearance of our program during runtime image as follows:
Code entered in this form are:
aà¥¤ Deklarasi variables and object, which contains the variable declaration and a new object

Private WithEvents audio As New clsAudio

Dim lstpathfiles As New ListBox

Dim indexlst As Integer

Dim animstart As Integer

Dim animlong As Integer

। .MenuFileList, related penginputan value to the ListBox in the file, namely lstFiles.
Private Sub mnuAddFolder_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuAddFolder.Click

Dim browse As New FolderBrowserDialog

With browse

.Description = "Pilih Alamat Folder Lagu"

.ShowDialog()

For Each file As System.IO.FileInfo In My.Computer.FileSystem.GetDirectoryInfo(.SelectedPath.ToString).GetFiles

If file.Extension.ToUpper = ".MP3" Or file.Extension.ToUpper = ".WAV" Or file.Extension.ToUpper = ".WMA" Or file.Extension.ToUpper = ".MID" Then

lstFiles.Items.Add(Strings.Left(file.Name, file.Name.Length - 4))

lstpathfiles.Items.Add(file.FullName)

End If

Next

End With

End Sub

Private Sub mnuAddFile_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuAddFile.Click

Dim openDg As New OpenFileDialog

With openDg

.Filter = "Supported Files (*.mp3, *.wav, *.wma, *.mid)|*.mp3;*.wav;*.wma;*.mid"

Dim dlgResult As DialogResult = .ShowDialog

If dlgResult = Windows.Forms.DialogResult.Cancel Then Exit Sub

Dim tmp As String = NamaFile(.FileName)

lstFiles.Items.Add(Strings.Left(tmp, tmp.Length - 4))

lstpathfiles.Items.Add(.FileName)

End With

End Sub

Private Sub mnuClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuClear.Click

If MsgBox("Hapus semua file yang ada ?", MsgBoxStyle.OkCancel) = MsgBoxResult.Ok Then

lstFiles.Items.Clear()

lstpathfiles.Items.Clear()

End If

End Sub

Private Function NamaFile(ByVal Fullpath As String) As String

Try

Return My.Computer.FileSystem.GetFileInfo(Fullpath).Name

Catch ex As Exception

Return ""

End Try

End Function

c। Tombol, associated with key Play, Stop and Pause. Private Sub btnPlay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPlay.Click

Playing()

End Sub

Private Sub btnStop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStop.Click

audio.StopAudio()

trbPlaying.Value = 0

lblPosisi.Text = "0:00"

Timer1.Enabled = False

End Sub

Private Sub btnPause_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPause.Click

If btnPause.Text = "Pause" Then

audio.PauseAudio()

btnPause.Text = "Resume"

Else

audio.ResumeAudio()

btnPause.Text = "Pause"

End If

End Sub
d। Muted Checkbox, related by the muted by some checkboxes.

Private Sub chkMuteAll_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles chkMuteAll.CheckedChanged

If chkMuteAll.Checked = True Then

audio.muteSoundOutput = True

Else

audio.muteSoundOutput = False

End If

End Sub

Private Sub chkLeftMute_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles chkLeftMute.CheckedChanged

If chkLeftMute.Checked = True Then

audio.leftChannelMute = True

Else

audio.leftChannelMute = False

End If

End Sub

Private Sub chkRightMute_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles chkRightMute.CheckedChanged

If chkRightMute.Checked = True Then

audio.rightChannelMute = True

Else

audio.rightChannelMute = False

End If

End Sub

e। TrackBar, related to the trackbar volume, the volume comparison between left and right, and trackbar track position।
Private Sub trbVolume_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles trbVolume.ValueChanged

audio.volumeLevel = trbVolume.Value * 200

End Sub

Private Sub trbPerbandingan_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles trbPerbandingan.ValueChanged

Select Case trbPerbandingan.Value

Case 0

audio.leftVolume = 0

audio.rightVolume = 1000

Case 1

audio.leftVolume = 333

audio.rightVolume = 1000

Case 2

audio.leftVolume = 1000

audio.rightVolume = 1000

Case 3

audio.leftVolume = 1000

audio.rightVolume = 333

Case 4

audio.leftVolume = 1000

audio.rightVolume = 0

End Select

End Sub

Private Sub trbPlaying_Scroll(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles trbPlaying.Scroll

audio.RubahPosisi(audio.DurasiInSec / trbPlaying.Maximum * trbPlaying.Value)

End Sub

f। Event clsAudio related to the events of clsAudio।
Private Sub audio_Berhenti() Handles audio.Berhenti

If indexlst <> lstpathfiles.Items.Count - 1 Then

indexlst = indexlst + 1

Else

If chkReplay.Checked = True Then

indexlst = 0

Else

Exit Sub

End If

End If

lstFiles.SelectedIndex = indexlst

Playing()

If Me.Visible = False Then

ico_Hide.ShowBalloonTip(10, "Judul", lstFiles.Items.Item(indexlst), ToolTipIcon.Info)

ico_Hide.Text = "Media Player" & vbCrLf & lstFiles.Items.Item(indexlst)

End If

End Sub

Private Sub audio_Playing() Handles audio.Playing

On Error Resume Next

lblSisaWaktu.Text = audio.formatSisaWaktu

trbPlaying.Value = audio.PosisiInSec

lblPosisi.Text = audio.formatPosisi

End Sub

g। Notify icon, associated with accessing the program icon in the systray।
Private Sub mnuNotifyIcon_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuNotifyIcon.Click, mnuHideico.Click

Me.Visible = False

ico_Hide.Text = "Media Player" & vbCrLf & lstFiles.Items.Item(indexlst)

End Sub

Private Sub mnuShow_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuShow.Click

Me.WindowState = FormWindowState.Normal

Me.Visible = False

Me.Visible = True

ico_Hide.Text = "Media Player"

End Sub

Private Sub mnuAbout_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuAbout.Click

MsgBox("Media Player Net V.1" & vbCrLf & "Created by Wardana", MsgBoxStyle.Information)

End Sub

Private Sub mnuExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuExit.Click

End

End Sub

h। others, contains the code other than the code above।
Private Sub lstFiles_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles lstFiles.Click

On Error Resume Next

lblJudul.Text = lstFiles.Items.Item(lstFiles.SelectedIndex)

indexlst = lstFiles.SelectedIndex

Playing()

End Sub

Private Sub Playing()

audio.StopAudio()

audio = Nothing

audio = New clsAudio

With audio

.filename = lstpathfiles.Items.Item(indexlst)

.PlayAudio()

trbPlaying.Maximum = .DurasiInSec

lblSisaWaktu.Text = .formatDurasi

trbVolume.Value = .volumeLevel / 200

End With

animstart = 0

animlong = lstFiles.Items.Item(indexlst).Length

trbPlaying.Value = 0

Timer1.Enabled = True

End Sub

Private Sub mnuDel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuDel.Click

On Error Resume Next

lstFiles.Items.RemoveAt(lstFiles.SelectedIndex)

lstpathfiles.Items.RemoveAt(lstFiles.SelectedIndex)

End Sub

Private Sub frmMusic_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing

audio.StopAudio()

audio.CloseAudio()

End Sub

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick

On Error Resume Next

If lstpathfiles.Items.Count <> 0 Then

If lstFiles.Items.Item(indexlst) = "" Then Exit Sub

animstart = animstart + 1

If animstart = animlong Then animstart = 0

lblJudul.Text = Strings.Right(lstFiles.Items.Item(indexlst), animlong - animstart) + " " + Strings.Left(lstFiles.Items.Item(indexlst), animstart)

End If

End Sub

End Class

This the codes that have been included in the program. Then this program and build on his exe files can be taken on location at the address debug folder, where the program is stored or the data we publish in a place.
~ Reference program is taken from a book by the name of the author of "Wardana".

2008-11-02T00:28:00.000-07:00

Developing the information system is not as easy as we imagine. The system is always accompanied with good information, good information, fast, accurate and relevant so that the parties will use more easily use it to make the decision.
The basic concept of the system is designed with data that is logically organized and centralized. This is called with the database used to store data with certain rules, so the party can be easier to use.
Blog that I make, aims to ease you learn in every system or database programs, which I attach here can help you in designing an application. Hopefully, programs or articles that I attach here can be useful for you.