如何訪問其他表單的列表

Question

我正在開發一個帶有人臉檢測的MP3播放器。我有兩種形式。

第一種形式是媒體播放器和人臉檢測代碼，第二種形式是創建播放列表的代碼。

我希望當我點擊創建按鈕時，播放列表的名稱應顯示在第一個表單的列表框中。

這是我的一些爲Form1代碼

private Capture cap; 
    public Form1() 
    { 
     InitializeComponent(); 

     cap = new Capture(0); 
     _dataBasePath = Directory.GetCurrentDirectory() + @"\db1.mdb"; 


     // adjust path to find your xml 

     haar = new HaarCascade("haarcascade_frontalface_alt_tree.xml"); 
     mouth = new HaarCascade("Mouth.xml"); 

     lefteye = new HaarCascade("eye_left.xml"); 
     righteye = new HaarCascade("haarcascade_righteye_2splits.xml"); 
    } 

    public void DataBasePath(string path) 
    { 
     _dataBasePath = path; 
    } 

    private void timer1_Tick(object sender, EventArgs e) 
    { 
     using (Image<Bgr, byte> nextFrame = cap.QueryFrame()) 
     { 
      if (nextFrame != null) 
      { 
       // there's only one channel (greyscale), hence the zero index 
       //var faces = nextFrame.DetectHaarCascade(haar)[0]; 
       Image<Gray, byte> grayframe = nextFrame.Convert<Gray, byte>(); 
       Image<Gray, Byte> gray = nextFrame.Convert<Gray, Byte>(); 
       Image<Gray, Byte> gray1 = nextFrame.Convert<Gray, Byte>(); 
       Image<Gray, Byte> gray2 = nextFrame.Convert<Gray, Byte>(); 
       var faces = grayframe.DetectHaarCascade(
         haar, 1.4, 4, 
         HAAR_DETECTION_TYPE.DO_CANNY_PRUNING, 
         new Size(nextFrame.Width/8, nextFrame.Height/8) 
         )[0]; 
       foreach (MCvAvgComp f in faces) 
       { 
        //draw the face detected in the 0th (gray) channel with blue color 
        nextFrame.Draw(f.rect, new Bgr(Color.Blue), 2); 
        facesnap = f.rect; 


        int halfheight = facesnap.Height/2; 
        int start = facesnap.X; 
        int start1 = facesnap.Y; 

        Rectangle top = new Rectangle(start,start1,facesnap.Width,halfheight); 
        int start2 = top.Bottom; 

        Rectangle bottom = new Rectangle(start, start2, facesnap.Width, halfheight); 


        //Set the region of interest on the faces 
        gray.ROI = bottom; 
        MCvAvgComp[][] mouthsDetected = gray.DetectHaarCascade(mouth, 
                1.1, 10, 
                Emgu.CV.CvEnum.HAAR_DETECTION_TYPE.DO_CANNY_PRUNING, 
                new Size(40,30)); 
        gray.ROI = Rectangle.Empty; 


        foreach (MCvAvgComp m in mouthsDetected[0]) 
        { 
         Rectangle mouthRect = m.rect; 
         mouthRect.Offset(bottom.X, bottom.Y); 
         nextFrame.Draw(mouthRect, new Bgr(Color.Red), 2); 
         Rectangle mouthphoto = new Rectangle(mouthRect.X - 5, mouthRect.Y - 10, mouthRect.Width + 5, mouthRect.Height +10); 
         detectedmouth = mouthphoto; 
        } 
        int halfwidth =facesnap.Width/2; 

        Rectangle toprighteye =new Rectangle(start,start1,halfwidth,halfheight); 
        int leftx = toprighteye.Right; 
        Rectangle toplefteye = new Rectangle(leftx, start1, halfwidth, halfheight); 

        gray1.ROI =toplefteye; 

        MCvAvgComp[][] detectedlefteye = gray1.DetectHaarCascade(lefteye, 1.1, 1, Emgu.CV.CvEnum.HAAR_DETECTION_TYPE.DO_CANNY_PRUNING, new Size(30,10)); 
        gray1.ROI = Rectangle.Empty; 

        foreach (MCvAvgComp eyesnapleft in detectedlefteye[0]) 
        { 
         Rectangle eyeRectleft = eyesnapleft.rect; 
         eyeRectleft.Offset(toplefteye.X, toplefteye.Y); 
         nextFrame.Draw(eyeRectleft, new Bgr(Color.Green), 2); 

         lefteyesnap = eyeRectleft; 


        } 

        gray2.ROI = toprighteye; 

        MCvAvgComp[][] detectedrighteye = gray2.DetectHaarCascade(righteye, 1.1, 1, Emgu.CV.CvEnum.HAAR_DETECTION_TYPE.DO_CANNY_PRUNING, new Size(30, 10)); 
        gray2.ROI = Rectangle.Empty; 

        foreach (MCvAvgComp eyesnapright in detectedrighteye[0]) 
        { 
         Rectangle eyeRectright = eyesnapright.rect; 
         eyeRectright.Offset(toprighteye.X, toprighteye.Y); 
         nextFrame.Draw(eyeRectright, new Bgr(Color.Yellow), 2); 

         righteyesnap = eyeRectright; 


        } 




       } 


       pictureBox1.Image = nextFrame.ToBitmap(); 
      } 
     } 

    } 
private void Form1_Load(object sender, EventArgs e) 
    { 
     _dataBasePath = Directory.GetCurrentDirectory() + @"\db1.mdb"; 


     // adjust path to find your xml 

     haar = new HaarCascade("haarcascade_frontalface_alt_tree.xml"); 
     mouth = new HaarCascade("Mouth.xml"); 

     lefteye = new HaarCascade("eye_left.xml"); 
     righteye = new HaarCascade("haarcascade_righteye_2splits.xml"); 
    } 

這是一些用於窗口2

namespace Face_Detection_Concept 
{ 
    public partial class Form2 : Form 
{ 
    #region Global Variables 

    public const string Separator = ","; 

    public static ArrayList searchAudio = new ArrayList(); 
    public static ArrayList searchVideo = new ArrayList(); 



    public static StreamWriter sw; 
    public string fnm; 
    #endregion 

    public Form2() 
    { 
     InitializeComponent(); 
    } 

    private void Form2_Load(object sender, EventArgs e) 
    { 
     // Set default values 
     cmbType.SelectedIndex = 0; 
     chkIncSubDir.Checked = true; 

     LoadFormats(); 


     txtFilename.Text = "PlayList1.wpl"; 
    } 

的代碼時，即時通訊使用的按鈕單擊事件訪問Form1的列表框的代碼

new Form1().playlistviewbar.items.add(playlistname); 

但這不顯示播放列表的名稱。有沒有解決方案？

Answer 1

設定ListBox的修飾語財產公開，你可以在已知的方式對其進行訪問。

將調用表單的引用傳遞給被調用表單，並將其用於訪問LB.

// Call: 
Form2 test = new Form2(this); 

//Constructor Form2: 
public Form2 (Form1 FormToAccess) 

//Access: 
FormToAccess.listBox1.... = ... ; 

Answer 2

您Capture對象cap爲空，啓動定時器，例如之前應該初始化：

public void form_load() 
    { 

     cap = new Capture(); 

     //Init and start Timer 

    } 

Answer 3

雖然你可以通過在public直接暴露控制，更好的方法是創建一個操作ListBox內容的方法。 ，讓您靈活地更改了控制而不會破壞調用形式：

public void AddPlayList(string playlistname) 
{ 
    this.playlistviewbar.Items.Add(playlistname); 
} 
public string[] GetPlayLists() 
{ 
    return this.playlistviewbar.Items; // converting to strings if necessary. 
}