ImageEn, unit imageenview

TIELayerNotify


Declaration

TIELayerNotify = procedure(Sender: TObject; layer: integer; event: TIELayerEvent) of object;


Description

layer is the layer index that is affected. WARNING: layer may not be a valid index (-1 or a removed index for some event types).
event specifies the event type:
Value Description
ielSelected User selected the layer
ielDeselected User deselected the layer
ielBeginResizing * User began to resize the layer (click down)
ielResizing User is resizing the layer
ielResized User finished resizing the layer
ielBeginMoving * User began to move the layer (click down)
ielMoving User is moving the layer
ielMoved User finished moving the layer
ielBeginRotating * User began to resize the layer (click down)
ielRotating User is rotating the layer
ielRotated User has finished rotating the layer
ielBeginCreating * Occurs as the user starts to create a layer using the mouse (dragging or clicking points). Layer index will be -1
ielCreating User is creating a layer using the mouse (dragging or clicking points)
ielNewLayer A new layer has been added by the user (but unlike ielCreated, may not have finished sizing it). This is the similar to the OnNewLayer event
ielCreated After a user had finished adding a new layer
ielAddedPoint User has added a point to a polyline layer
ielMovedPoint User is moving a point of a line or polyline layer
ielEditedPoints User has edited the points of a line or polyline layer
ielEditedProps User edited the properties of a layer, e.g. using the Layer Properties dialog
ielEdited User edited the text of a layer
ielTextEditorClick User has clicked the mouse or keyboard in the text editor for a TIETextLayer or TIELineLayer
ielTextEditorChange User has changed the mouse or keyboard in the text editor for a TIETextLayer or TIELineLayer (called for every change. Use ielEdited to detect once editing has completed)
ielBeforeRemove * Occurs before a layer is deleted due to a user action
ielRemoved * User has deleted a layer
ielLeftClicked User has clicked on a layer with the left mouse button (mouse up)
ielRightClicked User has clicked on a layer with the right mouse button (mouse up)
ielDblClicked User has double-clicked on a layer (Note: Does not occur for layer 0 unless LayerEditingMode is enabled)
ielMouseOver User has moved the cursor over a layer (Other than layer 0)
ielArranged User is changing the arrangement of layers (e.g. bringing a layer in front of another)
ielMerged User has merged layers (using an ImageEn Action)
ielGrouped User has grouped or ungrouped layers (using an ImageEn Action)
ielAction User has used an ImageEn Action that has changed the layers
* Does not occur with OnLayerNotify

Note:
This event only occurs once for each change, even if multiple layers are selected. You should review the list of selected layers to determine which changed
ielBeginCreating will return -1 as an index
ielBeforeRemove may return layer as LYR_ALL_LAYERS (-3) or LYR_SELECTED_LAYERS (-2)
ielRemoved will return an index for a layer that has been removed


Demo

Demo  Demos\LayerEditing\StampTextAndShapes\StampLayers.dpr


Examples

// Log all resizing of layers
procedure TfrmMain.IEView1LayerNotifyEx(Sender: TObject; layer: integer; event: TIELayerEvent);
var
  ALayer: TIELayer;
  i: Integer;
  sChangedLayers: string;
begin
  if event = ielResized then
  begin
    sChangedLayers := '';
    for i := 0 to IEView1.LayersCount - 1 do
    begin
      ALayer := IEView1.Layers[ I ];
      if ( ALayer.Locked = False ) and ALayer.Selected then
        sChangedLayers := sChangedLayers + IntToStr( i ) +',';
    end;
    if sChangedLayers <> '' then
    begin
      SetLength( sChangedLayers, Length( sChangedLayers ) - 1 );  // Remove final comma
      memLog.Lines.Add( 'Layers Resized: ' + sChangedLayers );
    end;
  end;
end;

// Auto-size text only after rotation
procedure TMainForm.ImageEnView1LayerNotifyEx(Sender: TObject; layer: Integer; event: TIELayerEvent);
begin
  if ( ImageEnView1.Layers[ layer ] is TIETextLayer ) and ( event is ielRotated ) then
  begin
    TIETextLayer( ImageEnView1.Layers[ layer ]).SizeToText();
    ImageEnView1.Update();
  end;
end;

// Refresh layer viewer (see TImageEnMView.AssignLayers) for any events that change the layers list, or the way layers look
procedure TMainForm.ImageEnView1LayerNotifyEx(Sender: TObject; layer: Integer; event: TIELayerEvent);
begin
  if event in [ ielSelected, ielDeselected, ielMoved, ielResized, ielRotated, ielCreated, ielMerged, ielGrouped, ielAction, ielEdited, ielEditedProps, ielEditedPoints, ielRemoved, ielArranged ] then
    RefreshLayerViewer();
end;

// Automatically merge added layers to the background (e.g. "Select to draw" shapes onto image)
procedure Tfmain.ImageEnView1LayerNotifyEx(Sender: TObject; layer: Integer; event: TIELayerEvent);
begin
  if AutoMergeLayers and ( layer >= 0 ) and ( layer < ImageEnView1.LayersCount ) then  // Ensure it is a valid layer
  begin
    // For text layers with automatic text editing (loAutoTextEditing in LayerOptions) don't merge till we complete editing
    if (( ImageEnView1.Layers[layer].Kind = ielkText ) and ( event = ielEdited )) or
       (( ImageEnView1.Layers[layer].Kind <> ielkText ) and ( event = ielCreated )) then
      ImageEnView1.LayersMerge( 0, layer );
  end;
end;