2013-07-16 103 views
2

我试图调用SHBrowseForFolder API来提示用户选择一个文件夹,我在树形控件的顶部看到标题静态/标签字段float。WinCE上的SHBrowseForFolder布局不正确

Folder browse with bad layout

代码是从在网络上在多个地方引用的article下载并从C#到VB.NET(它被滴加到现有的应用程序)的转换。

如果有人有任何提示,要么正确布局,请赐教。

调用代码很简单:

Using getLocDialog As New FolderBrowserDialog() 

    getLocDialog.Description = "This is a test" 
    getLocDialog.ShowDialog() 

    End Using 

接下来,这里是VB.NET版本的代码:

Public Class FolderBrowserDialog 
    Inherits CommonDialog 

    '--------------------------------------------------------------------------- 
    ' instance 
    '--------------------------------------------------------------------------- 

    Private info As BrowseInfo 
    Private folder As String = String.Empty 

    '--------------------------------------------------------------------------- 
    ' ctor 
    '--------------------------------------------------------------------------- 

    Public Sub New() 
     info = New BrowseInfo() 
     info.Title = String.Empty 
     InitCommonControls() 
    End Sub 

    '--------------------------------------------------------------------------- 
    ' public 
    '--------------------------------------------------------------------------- 

    Public Shadows Function ShowDialog() As DialogResult 

     Dim pitemidlist As IntPtr 

     Try 
     pitemidlist = SHBrowseForFolder(info.ToByteArray()) 
     Catch mme As MissingMethodException 
     Throw New PlatformNotSupportedException("Your platform doesn't support the SHBrowseForFolder API", mme) 
     End Try 

     If pitemidlist = IntPtr.Zero Then 
     Return DialogResult.Cancel 
     End If 

     '//maxpath unicode chars 
     Dim buffer As Byte() = New Byte(519) {} 
     Dim success As Boolean = SHGetPathFromIDList(pitemidlist, buffer) 
     '//get string from buffer 
     If success Then 

     folder = System.Text.Encoding.Unicode.GetString(buffer, 0, buffer.Length) 

     Dim nullindex As Integer = folder.IndexOf(Convert.ToChar(0)) 
     If nullindex <> -1 Then 
      folder = folder.Substring(0, nullindex) 
     End If 
     End If 
     LocalFree(pitemidlist) 

     Return DialogResult.OK 

    End Function 

    Public ReadOnly Property SelectedPath() As String 
     Get 
     Return folder 
     End Get 
    End Property 

    Public Property Description() As String 
     Get 
     Return info.Title 
     End Get 
     Set(ByVal value As String) 
     info.Title = value 
     End Set 
    End Property 

    '--------------------------------------------------------------------------- 
    ' private 
    '--------------------------------------------------------------------------- 

    <DllImport("commctrl", SetLastError:=True)> _ 
    Private Shared Sub InitCommonControls() 
    End Sub 

    <DllImport("ceshell", SetLastError:=True)> _ 
    Private Shared Function SHBrowseForFolder(ByVal lpbi As Byte()) As IntPtr 
    End Function 

    <DllImport("ceshell", SetLastError:=True)> _ 
    Private Shared Function SHGetPathFromIDList(ByVal pidl As IntPtr, ByVal pszPath As Byte()) As Boolean 
    End Function 

    <DllImport("coredll", SetLastError:=True)> _ 
    Private Shared Function LocalFree(ByVal ptr As IntPtr) As IntPtr 
    End Function 

    '--------------------------------------------------------------------------- 
    ' inner classes 
    '--------------------------------------------------------------------------- 


    Private Class BrowseInfo 

     Private m_data As Byte() 
     Private m_displayname As Byte() 
     Private m_title As Byte() 
     Private namehandle As GCHandle 
     Private titlehandle As GCHandle 

     Public Sub New() 

     m_data = New Byte(31) {} 
     m_displayname = New Byte(511) {} 
     m_title = New Byte(127) {} 

     namehandle = GCHandle.Alloc(m_displayname, GCHandleType.Pinned) 
     titlehandle = GCHandle.Alloc(m_title, GCHandleType.Pinned) 

     BitConverter.GetBytes(namehandle.AddrOfPinnedObject().ToInt32 + 4).CopyTo(m_data, 8) 
     BitConverter.GetBytes(titlehandle.AddrOfPinnedObject().ToInt32 + 4).CopyTo(m_data, 12) 

     End Sub 

     Public Function ToByteArray() As Byte() 
     Return m_data 
     End Function 

     Protected Overrides Sub Finalize() 
     namehandle.Free() 
     titlehandle.Free() 
     MyBase.Finalize() 
     End Sub 

     Public Property Title() As String 
     Get 
      Dim ttl As String = System.Text.Encoding.Unicode.GetString(m_title, 0, m_title.Length) 
      Dim nullindex As Integer = ttl.IndexOf(Convert.ToChar(0)) 
      If nullindex = -1 Then 

       Return ttl 
      End If 
      Return ttl.Substring(0, ttl.IndexOf(Convert.ToChar(0))) 
     End Get 
     Set(ByVal value As String) 
      Dim titlebytes As Byte() = System.Text.Encoding.Unicode.GetBytes(value & Convert.ToChar(0)) 
      If titlebytes.Length > m_title.Length Then 
       Throw New ArgumentException("Description must be no longer than 64 characters") 
      End If 
      Try 
       Buffer.BlockCopy(titlebytes, 0, m_title, 0, titlebytes.Length) 
      Catch ex As Exception 
      End Try 
     End Set 
     End Property 

     Public Property FileName() As String 
     Get 
      Dim fn As String = System.Text.Encoding.Unicode.GetString(m_displayname, 0, m_displayname.Length) 
      Dim nullindex As Integer = fn.IndexOf(Convert.ToChar(0)) 
      If nullindex = -1 Then 
       Return fn 
      End If 
      Return fn.Substring(0, fn.IndexOf(Convert.ToChar(0))) 
     End Get 
     Set(ByVal value As String) 
      Dim filenamebytes As Byte() = System.Text.Encoding.Unicode.GetBytes(value & Convert.ToChar(0)) 
      If filenamebytes.Length > m_title.Length Then 
       Throw New ArgumentException("SelectedFolder must be no longer than 256 characters") 
      End If 
      Buffer.BlockCopy(filenamebytes, 0, m_displayname, 0, filenamebytes.Length) 
     End Set 
     End Property 

     '/*HWND hwndOwner; 
     'LPCITEMIDLIST pidlRoot; 
     'LPTSTR pszDisplayName; 
     'LPCTSTR lpszTitle; 
     'UINT ulFlags; 
     'BFFCALLBACK lpfn; 
     'LPARAM lParam; 
     'int iImage;*/ 

    End Class 

End Class 

原来的C#是这样的:

public class FolderBrowserDialog : CommonDialog 
    { 
     private BrowseInfo info; 
     private string folder = string.Empty; 

     /// <summary> 
     /// Initializes a new instance of the FolderBrowserDialog class. 
     /// </summary> 
     public FolderBrowserDialog() 
     { 
      info = new BrowseInfo(); 
      info.Title = string.Empty; 
      InitCommonControls(); 
     } 

     /// <summary> 
     /// Runs a common dialog box with a default owner. 
     /// </summary> 
     /// <returns></returns> 
     public new DialogResult ShowDialog() 
     { 
      IntPtr pitemidlist; 

      try 
      { 
       pitemidlist = SHBrowseForFolder(info.ToByteArray()); 
      } 
      catch(MissingMethodException mme) 
      { 
       throw new PlatformNotSupportedException("Your platform doesn't support the SHBrowseForFolder API",mme); 
      } 

      if(pitemidlist==IntPtr.Zero) 
      { 
       return DialogResult.Cancel; 
      } 

      //maxpath unicode chars 
      byte[] buffer = new byte[520]; 
      bool success = SHGetPathFromIDList(pitemidlist, buffer); 
      //get string from buffer 
      if(success) 
      { 
       folder = System.Text.Encoding.Unicode.GetString(buffer, 0, buffer.Length); 

       int nullindex = folder.IndexOf('\0'); 
       if(nullindex!=-1) 
       { 
        folder = folder.Substring(0, nullindex); 
       } 
      } 
      LocalFree(pitemidlist); 

      return DialogResult.OK; 
     } 

     /// <summary> 
     /// Gets the path selected by the user. 
     /// </summary> 
     public string SelectedPath 
     { 
      get 
      { 
       return folder; 
      } 
     } 

     /// <summary> 
     /// Gets or sets the descriptive text displayed above the tree view control in the dialog box. 
     /// </summary> 
     public string Description 
     { 
      get 
      { 
       return info.Title; 
      } 
      set 
      { 
       info.Title = value; 
      } 
     } 


     #region P/Invokes 

     [DllImport("commctrl", SetLastError=true)] 
     private static extern void InitCommonControls(); 

     [DllImport("ceshell", SetLastError=true)] 
     private static extern IntPtr SHBrowseForFolder(byte[] lpbi); 

     [DllImport("ceshell", SetLastError=true)] 
     private static extern bool SHGetPathFromIDList(IntPtr pidl, byte[] pszPath); 

     [DllImport("coredll", SetLastError=true)] 
     private static extern IntPtr LocalFree(IntPtr ptr); 

     #endregion 

     #region helper class for BROWSEINFO struct 
     private class BrowseInfo 
     { 
      private byte[] m_data; 
      private byte[] m_displayname; 
      private byte[] m_title; 
      private GCHandle namehandle; 
      private GCHandle titlehandle; 

      public BrowseInfo() 
      { 
       m_data = new byte[32]; 
       m_displayname = new byte[512]; 
       m_title = new byte[128]; 

       namehandle = GCHandle.Alloc(m_displayname, GCHandleType.Pinned); 
       titlehandle = GCHandle.Alloc(m_title, GCHandleType.Pinned); 

       BitConverter.GetBytes((int)namehandle.AddrOfPinnedObject() + 4).CopyTo(m_data, 8); 
       BitConverter.GetBytes((int)titlehandle.AddrOfPinnedObject() + 4).CopyTo(m_data, 12); 
      } 

      public byte[] ToByteArray() 
      { 
       return m_data; 
      } 

      ~BrowseInfo() 
      { 
       namehandle.Free(); 
       titlehandle.Free(); 
      } 

      public string Title 
      { 
       get 
       { 
        string title = System.Text.Encoding.Unicode.GetString(m_title, 0, m_title.Length); 
        int nullindex = title.IndexOf('\0'); 
        if(nullindex==-1) 
        { 
         return title; 
        } 
        return title.Substring(0, title.IndexOf('\0')); 
       } 
       set 
       { 
        byte[] titlebytes = System.Text.Encoding.Unicode.GetBytes(value + '\0'); 
        if(titlebytes.Length > m_title.Length) 
        { 
         throw new ArgumentException("Description must be no longer than 64 characters"); 
        } 
        try 
        { 
         Buffer.BlockCopy(titlebytes, 0, m_title,0, titlebytes.Length); 
        } 
        catch 
        { 
        } 
       } 
      } 

      public string FileName 
      { 
       get 
       { 
        string filename = System.Text.Encoding.Unicode.GetString(m_displayname, 0, m_displayname.Length); 
        int nullindex = filename.IndexOf('\0'); 
        if(nullindex==-1) 
        { 
         return filename; 
        } 
        return filename.Substring(0, filename.IndexOf('\0')); 
       } 
       set 
       { 
        byte[] filenamebytes = System.Text.Encoding.Unicode.GetBytes(value + '\0'); 
        if(filenamebytes.Length > m_title.Length) 
        { 
         throw new ArgumentException("SelectedFolder must be no longer than 256 characters"); 
        } 
        Buffer.BlockCopy(filenamebytes, 0, m_displayname,0, filenamebytes.Length); 
       } 
      } 

         /*HWND hwndOwner; 
         LPCITEMIDLIST pidlRoot; 
         LPTSTR pszDisplayName; 
         LPCTSTR lpszTitle; 
         UINT ulFlags; 
         BFFCALLBACK lpfn; 
         LPARAM lParam; 
         int iImage;*/ 

     } 
     #endregion 
    } 

其他详细信息:开发环境是Visual Studio 2008,Compact Framework 3.5。该设备运行Windows CE 4.2。

回答

1

我与SHBrowseForFolderFolderBrowserDialog和Windows CE 5.0有相同的经验。

解决方法可能是为标志设置BIF_STATUSTEXT。通过这种方式,布局会被移位并且标题会出现在TreeView上方。

为此,请将数据成员uint m_flags添加到BrowseInfo类。在它的构造函数中添加:

const uint BIF_STATUSTEXT = 0x00000004; 
m_flags |= BIF_STATUSTEXT; 

而在ToByteArray()方法Add:

BitConverter.GetBytes(m_flags).CopyTo(m_data, 16); 
+0

我得给一个尝试,谢谢你的提示。 – tcarvin

+0

没有工作。当标题标签被压抑时,它导致了treeview的顶部向下滑动,使得对话的前30%只是空白。 – tcarvin