Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>In order to set a watermark in the listview you need to use the <a href="http://msdn.microsoft.com/en-us/library/bb761155%28VS.85%29.aspx" rel="nofollow">LVM_SETBKIMAGE</a> message, and you need to override the TListView's default WM_ERASEBKGND message. The listview takes ownership of the bitmap handle, so you need to use TBitmap's <code>ReleaseHandle</code>, rather than just <code>Handle</code>.</p> <p>If you want it aligned to the top-left, instead of the bottom right like Explorer, use <code>LVBKIF_SOURCE_HBITMAP</code> instead of <code>LVBKIF_TYPE_WATERMARK</code> for the <code>ulFlags</code> value.</p> <pre><code>uses CommCtrl, ...; type TListView = class(ComCtrls.TListView) protected procedure WndProc(var Message: TMessage); override; end; TForm4 = class(TForm) ListView1: TListView; procedure FormCreate(Sender: TObject); end; procedure TListView.WndProc(var Message: TMessage); begin if Message.Msg = WM_ERASEBKGND then DefaultHandler(Message) else inherited WndProc(Message); end; procedure TForm4.FormCreate(Sender: TObject); var Img: TImage; BkImg: TLVBKImage; begin FillChar(BkImg, SizeOf(BkImg), 0); BkImg.ulFlags := LVBKIF_TYPE_WATERMARK; // Load image and take ownership of the bitmap handle Img := TImage.Create(nil); try Img.Picture.LoadFromFile('C:\Watermark.bmp'); BkImg.hbm := Img.Picture.Bitmap.ReleaseHandle; finally Img.Free; end; // Set the watermark SendMessage(ListView1.Handle, LVM_SETBKIMAGE, 0, LPARAM(@BkImg)); end; </code></pre> <p><strong>Stretched Watermark</strong></p> <p>The listview doesn't natively support stretching a bitmap across the entire background. To do so you need to do a StretchBlt in response to WM_ERASEBKGND yourself.</p> <pre><code>type TMyListView = class(TListView) protected procedure CreateHandle; override; procedure CreateParams(var Params: TCreateParams); override; procedure WMEraseBkgnd(var Msg: TWMEraseBkgnd); message WM_ERASEBKGND; public Watermark: TBitmap; end; procedure TMyListView.CreateHandle; begin inherited; // Set text background color to transparent SendMessage(Handle, LVM_SETTEXTBKCOLOR, 0, CLR_NONE); end; procedure TMyListView.CreateParams(var Params: TCreateParams); begin inherited; // Invalidate every time the listview is resized Params.Style := Params.Style or CS_HREDRAW or CS_VREDRAW; end; procedure TMyListView.WMEraseBkgnd(var Msg: TWMEraseBkgnd); begin StretchBlt(Msg.DC, 0, 0, Width, Height, Watermark.Canvas.Handle, 0, 0, Watermark.Width, Watermark.Height, SrcCopy); Msg.Result := 1; end; </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POhow to set background image to TListview in Delphi XE?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USZoë Peterson
    1. USZoë Peterson
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COvery thanks. I put your code's in the project, but has error and doesn't work.can you solve it, Please. (http://4shared.com/file/ImTrNd-Z/lvdemo_edited.html )
      singulars
      1. PO
      1. USUser
    2. COIf you look at the code I posted, "Watermark" is a TBitmap field/property I added to TMyListView. You need to assign that instead of using LVM_SETBKIMAGE. LVM_SETBKIMAGE doesn't support stretching, so you can't use it. Also, it looks like setting the CS_HREDRAW/CS_VREDRAW styles in CreateParams messes up the drawing. Remove that and manually invalidate it in the ListView's OnResize event handler.
      singulars
      1. PO
      1. USZoë Peterson
    3. COAlso, in the code you posted, you have a TwpListView where you're adding the code, but your types are declared as TListView. You need to do the aliasing like I did in my first code sample, or create the TwpListView at runtime. As it is, none of the code in there is getting executed.
      singulars
      1. PO
      1. USZoë Peterson
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload