Listview中的奇怪字符

Question

我有一个 Android 项目的代码，用于自动调整 Listview 文本的高度。在固定高度下一切正常。当我激活此代码LText.Height := ListView1.getItemTextHeight(LText)+10; 时，自动高度工作正常，但带有粗体上的奇怪字符，有时还会出现“不允许重复”错误消息。 在 Windows 中工作正常，但在 Android 上我有这个。

    for i := 0 to FDMemTable1.RecordCount -1 do
      begin
        UName := (FDMemTable1.FieldByName('username').Value);
        Descr := (FDMemTable1.FieldByName('descr').Value);
        Ext := (FDMemTable1.FieldByName('ext').Value);
        Url := (FDMemTable1.FieldByName('vurl').Value);
        FCanUpdate := False;
        LItem := ListView1.Items.Add;
        LItem.Data['UName'] := UName;
        LItem.Data['Descr'] := Descr;
        LItem.Data['Ext'] := Ext;
        LItem.Data['Url'] := Url;
        FCanUpdate := True;
        LItem.Adapter.ResetView(LItem);
        FDMemTable1.Next;
      end;
    ListView1.EndUpdate;
end;

procedure TForm7.ListView1UpdatingObjects(const Sender: TObject;
  const AItem: TListViewItem; var AHandled: Boolean);
var
  h: integer;
  LText: TListItemText;
begin
  h := 2;
  LText := AItem.Objects.FindObjectT<TListItemText>('UName_text');
  if LText = nil then
    begin
      LText := TListItemText.Create(AItem);
      LText.Name := 'UName_text';
      LText.PlaceOffset.X := 18;
      LText.PlaceOffset.Y := h;
      LText.TextColor := TAlphaColorRec.Black;
      LText.TextAlign := TTextAlign.Leading;
      LText.TextVertAlign := TTextAlign.Leading;
      LText.Font.Size := 14;
      LText.Font.Style := [TFontStyle.fsBold];
    end;
  LText.Width := (Sender as TListView).Width - 18;
  LText.Text := AItem.Data['UName'].AsString;
  LText.Height := 22;
  h := Round(h + LText.Height +7);

  if AItem.Data['Descr'].AsString <> '' then
  begin
    LText := AItem.Objects.FindObjectT<TListItemText>('Descr_text');
    if LText = nil then
      begin
        LText := TListItemText.Create(AItem);
        LText.Name := 'Descr_text';
        LText.PlaceOffset.X := 18;
        LText.PlaceOffset.Y := h;
        LText.TextColor := TAlphaColorRec.Black;
        LText.TextAlign := TTextAlign.Leading;
        LText.TextVertAlign := TTextAlign.Leading;
        LText.WordWrap := True;
        LText.Font.Size := 13;
        LText.Font.Style := [];
      end;
    LText.Width := (Sender as TListView).Width - 20;
    LText.Text := AItem.Data['Descr'].AsString;

//    LText.Height := ListView1.getItemTextHeight(LText)+10;

    LText.Height := 30;

    h := Round(h + LText.Height + 5);
  end;
  AItem.Height := h;
  AHandled := True;
end;

我手机的截图。

这是怎么回事？？？

Answer 1

我发现这段代码有问题。 我将此过程称为 TThread.CreateAnonymousThread。 当我删除这一切都很好。我发布了正确的代码以使用代码创建 ListView 项目（在本例中为 2 个文本和 1 个来自 url 的图像）。

procedure TForm9.LVC;
var
  i, TLikes, LVIHeight, ImgH, ImgW: integer;
  UName, Descr, Ext, ThumbUrl, Url: UnicodeString;
  LItem : TListViewItem;
begin
  RESTRequest1.Execute;
  FDMemTable1.First;
  for i := 0 to FDMemTable1.RecordCount -1 do
begin
  UName := FDMemTable1.FieldByName('username').Value;
  Descr := FDMemTable1.FieldByName('descr').Value;
  Ext := FDMemTable1.FieldByName('ext').Value;
  ThumbUrl := FDMemTable1.FieldByName('image_url').Value;
  Url := FDMemTable1.FieldByName('vurl').Value;
  TLikes := FDMemTable1.FieldByName('TotalLikes').Value;
  if FDMemTable1.FieldByName('imgh').Value <>  '' then
    begin
      ImgH := StrToInt(FDMemTable1.FieldByName('imgh').Value);
      ImgW := StrToInt(FDMemTable1.FieldByName('imgw').Value);
      LVIHeight := round((ListView1.Width / ImgW) * ImgH);
    end
  else
    begin
      ImgH := 0;
      ImgW := 0;
      LVIHeight := 0;
    end;
  ListView1.BeginUpdate;
    FCanUpdate := False;
    LItem := ListView1.Items.Add;
    LItem.Data['UName'] := UName;
    LItem.Data['Descr'] := Descr;
    LItem.Data['Ext'] := Ext;
    LItem.Data['ThumbUrl'] := ThumbUrl;
    LItem.Data['Url'] := Url;
    LItem.Data['Likes'] := TLikes;
    LItem.Data['ImgH'] := ImgH;
    LItem.Data['ImgW'] := ImgW;
    LItem.Data['LVIHeight'] := LVIHeight;
    FCanUpdate := True;
    LItem.Adapter.ResetView(LItem);
  ListView1.EndUpdate;
  FDMemTable1.Next;
end;
end;

procedure TForm9.FormCreate(Sender: TObject);
begin
  FCanUpdate := True;
end;

procedure TForm9.FormShow(Sender: TObject);
begin
   LVC;
end;

procedure TForm9.ListView1UpdatingObjects(const Sender: TObject;
  const AItem: TListViewItem; var AHandled: Boolean);
var
  h: integer;
  LText: TListItemText;
  LImage: TListItemImage;
  LImageURL: String;
  foto : TBitmap;
begin
  if not FCanUpdate then
    Exit;

  h := 2;
  LText := AItem.Objects.FindObjectT<TListItemText>('UName_text');
  if LText = nil then
   begin
     LText := TListItemText.Create(AItem);
     LText.Name := 'UName_text';
     LText.PlaceOffset.X := 18;
     LText.PlaceOffset.Y := h;
     LText.TextColor := TAlphaColorRec.Black;
     LText.TextAlign := TTextAlign.Leading;
     LText.TextVertAlign := TTextAlign.Leading;
     LText.Font.Size := 14;
     LText.Font.Style := [TFontStyle.fsBold];
   end;
  LText.Width := (Sender as TListView).Width - 18;
  LText.Text := AItem.Data['UName'].AsString;
  LText.Height := 22;
  h := Round(h + LText.Height +7);

  if AItem.Data['ThumbUrl'].AsString <> '' then
  begin
    LImage := AItem.Objects.FindObjectT<TListItemImage>('MImage');
    if LImage = nil then
    begin
      LImage := TListItemImage.Create(AItem);
      LImage.Name := 'MImage';
      LImage.Bitmap:=Nil;
      LImage.Align := TListitemalign.Leading;
      LImage.VertAlign := TListItemAlign.Leading;
      LImage.ScalingMode := TImageScalingMode.StretchWithAspect;
      LImage.PlaceOffset.X := 0;
      LImage.PlaceOffset.Y := h;
      LImage.Bitmap := TBitmap.Create;
      LImage.OwnsBitmap := True;
      LImage.Visible := True;
    end;
    LImage.Width := ListView1.Width;
    LImage.Height := AItem.Data['LVIHeight'].AsInteger;
    LImageURL := AItem.Data['ThumbUrl'].AsString;
      TThread.CreateAnonymousThread(
         procedure
            begin
              foto := TBitmap.Create;
              fnLoadImgFromUrl(LImageURL, foto);
              LImage.OwnsBitmap := True;
              LImage.Bitmap := foto;
            end).Start;
    h := Round(h + LImage.Height + 5);
  end;

  if AItem.Data['Descr'].AsString <> '' then
  begin
    LText := AItem.Objects.FindObjectT<TListItemText>('Descr_text');
    if LText = nil then
      begin
        LText := TListItemText.Create(AItem);
        LText.Name := 'Descr_text';
        LText.PlaceOffset.X := 18;
        LText.PlaceOffset.Y := h;
        LText.TextColor := TAlphaColorRec.Black;
        LText.TextAlign := TTextAlign.Leading;
        LText.TextVertAlign := TTextAlign.Leading;
        LText.WordWrap := True;
        LText.Font.Size := 13;
        LText.Font.Style := [];
      end;
    LText.Width := (Sender as TListView).Width - 20;
    LText.Text := AItem.Data['Descr'].AsString;
    LText.Height := ListView1.getItemTextHeight(LText)+10;
    h := Round(h + LText.Height + 5);
  end;
  AItem.Height := h;
  AHandled := True;
end;