In Delphi 10.2 Tokyo I use a TAniIndicator until the database is loaded.
By default, the color of the bubble is black. I would like to change it to be white without creating a Style. I haven't found any property for that.
Is there any way to change it?
You can do something like this (for default style), note that you'll need to improve ReplaceBlackColor function to make bubble completely white
procedure ReplaceBlackColor(const ABitmap: TBitmap);
var
I, J: Integer;
M: TBitmapData;
C: PAlphaColorRec;
begin
if ABitmap.Map(TMapAccess.ReadWrite, M) then
try
for J := 0 to ABitmap.Height - 1 do
for I := 0 to ABitmap.Width - 1 do
begin
C := #PAlphaColorArray(M.Data)[J * (M.Pitch div 4) + I];
if C^.Color = TAlphaColorRec.Black then
C^.Color := TAlphaColorRec.White;
end;
finally
ABitmap.Unmap(M);
end;
end;
procedure TForm3.Button1Click(Sender: TObject);
var
bla: TBitmapListAnimation;
begin
bla := AniIndicator1.FindStyleResource('ani') as TBitmapListAnimation;
ReplaceBlackColor(bla.AnimationBitmap);
end;
Add a TFillRGBEffect to the indicator control and set its Color property to desired color.
TFillRGBEffect, like other effects, will apply to any controls "below" it, so you can repaint whole UI in just one go.
The scenario is this:
I've created a Delphi (XE2) form.
On it is a single TGroupBox (or other control) stretched so it occupies the full width of the form with the top.
Right anchor (in addition to left and top) on TGroupBox is set.
Form width set to 1200px (to illustrate the point).
If I run this application on a monitor whose Screen.Width property is greater than 1200px (I'm running without any DPI virtualization AFAIK) then the TGroupBox renders as you'd expect.
However.. if the monitor's width is less than 1200px then the right hand portion of the control is missing from the screen regardless of how your resize the form.
I've overridden the Create() method of my form with the override; directive and verified that I'm setting the width property correctly, however the control is still cropped.
Can anyone advise either how to:
a) set the width property of the form such that it is affects the positioning of the child components or...
b) suggest a way to force a relayout of all child components once the form is rendered?
Tracing the code to see what happens, I came up with the below adjustment.
procedure TForm1.WMWindowPosChanging(var Message: TWMWindowPosChanging);
var
MessageWidth: Integer;
begin
MessageWidth := Message.WindowPos.cx;
inherited;
if MessageWidth > Message.WindowPos.cx then
GroupBox1.Width := GroupBox1.Width - MessageWidth + Message.WindowPos.cx;
end;
This is not a generalized solution, but it makes clear what the problem is. VCL asks for a window size for its form which is not granted by the OS since it is larger then the desktop. From then on the form resumes anchoring the child control with its design time specified width which is larger than the client width of the form, thus right side of the child control overflows.
Another solution can be to override handling of WM_GETMINMAXINFO message to let the OS grant the asked width.
procedure TForm1.WMGetMinMaxInfo(var Message: TWMGetMinMaxInfo);
begin
inherited;
Message.MinMaxInfo.ptMaxTrackSize.X := 1200;
end;
This may not be a good solution because then the form will be larger than the desktop.
Regarding your 'a' and 'b' items, I don't think 'b' is possible - or at least not possible to make the VCL relayout by itself - because VCL defers applying anchor rules until after the component (form) is done loading. By then, the form's width is different than the design time width but child controls' placement remain unaffected. No amount of forcing to layout will make them in sync again.
However it should possible to recalculate everything from scratch if your own code keeps a reference to the design time width. Below is not complete code.
type
TForm1 = class(TForm)
..
private
FAdjustShrinkWidth, FAdjustShrinkHeight: Integer;
protected
procedure Loaded; override;
public
procedure SetBounds(ALeft: Integer; ATop: Integer; AWidth: Integer;
AHeight: Integer); override;
end;
...
procedure TForm1.SetBounds(ALeft, ATop, AWidth, AHeight: Integer);
var
TrackWidth, TrackHeight: Boolean;
begin
TrackWidth := AWidth = 1200;
TrackHeight := AHeight = ??;
inherited;
if TrackWidth and (Width < AWidth) then
FAdjustShrinkWidth := AWidth - Width;
if TrackHeight and (Height < AHeight) then
FAdjustShrinkHeight := AHeight - Height;
end;
procedure TForm1.Loaded;
procedure ReadjustControlAnchors(Control: TWinControl);
var
i: Integer;
begin
for i := 0 to Control.ControlCount - 1 do
if (akRight in Control.Controls[i].Anchors) or (akBottom in Control.Controls[i].Anchors) then begin
Control.Controls[i].Left := // some complex calculation depending on the anchors set;
Control.Controls[i].Top := // same as above;
Control.Controls[i].Width := // same as above;
Control.Controls[i].Height := // same as above;
if (Control.Controls[i] is TWinControl) and (TWinControl(Control.Controls[i]).ControlCount > 0) then
ReadjustControlAnchors(TWinControl(Control.Controls[i]));
end;
end;
begin
inherited;
ReadjustControlAnchors(Self);
end;
I have no idea how to fill in the blanks in the above code. Reading and tracing VCL code may be compulsory to imitate VCL anchoring.
I can't think of anything for 'a'.
Update:
VCL has actually left a backdoor for a control to lie to its immediate children about their parent's size while they are anchoring. Documentation explains it a bit different:
UpdateControlOriginalParentSize is a protected method that updates the
original size of the parent control. It is used internally to update
the anchor rules of the control.
We can use it to tell the groupbox the intended original size.
type
TForm1 = class(TForm)
..
private
FWidthChange, FHeightChange: Integer;
protected
procedure UpdateControlOriginalParentSize(AControl: TControl;
var AOriginalParentSize: TPoint); override;
public
procedure SetBounds(ALeft: Integer; ATop: Integer; AWidth: Integer;
AHeight: Integer); override;
end;
...
procedure TForm1.SetBounds(ALeft, ATop, AWidth, AHeight: Integer);
var
RequestedWidth, RequestedHeight: Integer;
begin
RequestedWidth := AWidth;
RequestedHeight := AHeight;
inherited;
if csLoading in ComponentState then begin
if RequestedWidth <> Width then
FWidthChange := Width - AWidth;
if RequestedHeight <> Height then
FHeightChange := Height - AHeight;
end;
end;
procedure TForm1.UpdateControlOriginalParentSize(AControl: TControl;
var AOriginalParentSize: TPoint);
begin
inherited;
if akRight in AControl.Anchors then
AOriginalParentSize.X := AOriginalParentSize.X - FWidthChange;
if akBottom in AControl.Anchors then
AOriginalParentSize.Y := AOriginalParentSize.Y - FHeightChange;
end;
I note again that this will affect the form's immediate children only. Should the groupbox hosts controls that anchors right and bottom, it also has to override the same method.
Also note that this will not undo the fact that the form's width has changed. That's if there was a left anchored control that's at the far right of the form, it will not replace itself to client boundary. It will act as if the form's width has been decreased, i.e. remain out of sight.
I would like implement automatically resizing buttons keeping the same width when some buttons are invisible. I used code prepared by Andreas Rejbrand at this link, but the issue is more complicated when I set some buttons invisible. In places where we have invisible buttons there are gaps.
My idea is to check how many buttons are invisible and next set btnWidth depending on the amount of visible buttons. I don't actually know how I can check if buttons are invisible in this case.
I want to use TAdvGlowButton component for the buttons and TPanel component for the panel and add OnResize procedure to panel like below:
procedure TForm3.Panel4Resize(Sender: TObject);
var
i: Integer;
btnWidth: Integer;
begin
btnWidth := Panel4.Width div Panel4.ControlCount;
for i := 0 to Panel4.ControlCount - 1 do
begin
Panel4.Controls[i].Left := i * btnWidth;
Panel4.Controls[i].Width := btnWidth;
end;
end;
Could you give me any idea how to solve this issue?
procedure TForm3.Panel4Resize(Sender: TObject);
const
cLeftMargin = 10; //Margin at the left side of the group of buttons
cSpacing = 10; //Spacing/Margin between the buttons
cRightMargin = 10; //Margin at the right side of the group of buttons
var
i, VisibleControls, lLeft: Integer;
btnWidth: Integer;
begin
//count number of visible controls
VisibleControls := 0;
for i := 0 to Panel4.ControlCount - 1 do
if Panel4.Controls[i].Visible then
inc(VisibleControls);
btnWidth := (Panel4.Width-cLeftMargin-cRightMargin - cSpacing*(VisibleControls-1)) div VisibleControls;
//distribute the visible controls
lLeft := cLeftMargin;
for i := 0 to Panel4.ControlCount - 1 do
if Panel4.Controls[i].Visible then
begin
Panel4.Controls[i].Left := lLeft;
Panel4.Controls[i].Width := btnWidth;
lLeft := lLeft + btnWidth + cSpacing;
end;
end;
I am using a TFlowLayout to display a number of boxes.
When the screen is resized the FlowLayout adjusts the number of boxes per line automatically.
However I want to adjust the height of the surrounding element (TTreeViewItem) automatically.
I achieved this by adding an event:
procedure TDeviceTreeView.DeviceTreeViewResize(Sender: TObject);
begin
height := ChildrenRect.Height;
end;
This works halfways: the size is adjusted to grow when the elements in the flow layout need more lines.
However it never shrinks.
I know why. If you look at TControl.GetChildrenRect you will see:
function TControl.GetChildrenRect: TRectF;
var
I: Integer;
Control: TControl;
begin
Result := AbsoluteRect;
{ children }
if not (ClipChildren or SmallSizeControl) and (FControls <> nil) then
for I := GetFirstVisibleObjectIndex to GetLastVisibleObjectIndex - 1 do
begin
Control := FControls[I];
if Control.Visible then
Result := UnionRect(Result, Control.GetChildrenRect);
end
end;
Note that the base rectangle is:
Result := AbsoluteRect;
And from that it will loop through the child controls, always adding (union) to the first rect.
This causes the behavior you are experiencing: if the ChildControl's rect surpasses the FlowLayout's rect it increases, but will never decrease because the FlowLayout.AbsoluteRect is the starting rect in the function.
What you can do to solve that in a simple way is calculating the "ChildRect" yourself.
procedure TDeviceTreeView.DeviceTreeViewResize(Sender: TObject);
var childrenRect: TRectF;
begin
if ((csLoading in FlowLayout1.ComponentState) = False) then // You might want to check for csLoading to avoid unecessary calls to resize
begin
childrenRect := TRectF.Empty;
for i := 0 to FlowLayout1.ControlsCount - 1 do
childrenRect := TRectF.Union(childrenRect, FlowLayout1.Controls[i].ChildrenRect);
FlowLayout1.Height := childrenRect.Height;
end;
end;
You need to set TTreeViewItem property Align:alTop. In FMX it looks like: TTreeViewItem.Align:=talignlayout(1);
As a kind of self-study exercise, I've made a form which contains six panels in a 2x3 rectangle and I want them to switch between visible and invisible one after another. I'm trying to do so by using a for loop of some kind. I could of course write something like:
Panel1.Visible := true;
Panel1.Visible := false;
Panel2.Visible := true;
Panel2.Visible := false;
Panel3.Visible := true;
etc. etc.
But this takes quite a lot of typing and is pretty inefficient when I decide I want it to wait for 100ms between each step. For example, I'd then have to edit all the six steps to wait. This is doable for six steps, but maybe another time I want to do it a hundred times! So I'm thinking there must also be a way to use a for loop for this, where a variable varies from 1 to 6 and is used in the object identifier. So it would something like this:
for variable := 1 to 6 do begin
Panel + variable.Visible := true;
Panel + variable.Visible := false;
end;
Now, this obviously doesn't work, but I hope somebody here can tell me if this is in fact possible and if yes, how. Maybe I can use a string as the identifier? My explanation is probably pretty bad because I don't know all the technical terms but I hope the code explains something.
You can loop through the panel's Owner's Components array.
var
i: Integer;
TmpPanel: TPanel;
begin
{ This example loops through all of the components on the form, and toggles the
Visible property of each panel to the value that is opposite of what it has (IOW,
if it's True it's switched to False, if it's False it's switched to True). }
for i := 0 to ComponentCount - 1 do
if Components[i] is TPanel then
begin
TmpPanel := TPanel(Components[i]);
TmpPanel.Visible := not TmpPanel.Visible; // Toggles between true and false
end;
end;
You can also use the FindComponent method, if you want a very specific type of component by name. For instance, if you have the 6 panels, and their names are Panel1, Panel2, and so forth:
var
i: Integer;
TmpPanel: TPanel;
begin
for i := 1 to 6 do
begin
TmpPanel := FindComponent('Panel' + IntToStr(i)) as TPanel;
if TmpPanel <> nil then // We found it
TmpPanel.Visible := not TmpPanel.Visible;
end;
end;
This is a situation where you want to create the controls dynamically at runtime rather than at designtime. Trying to grapple with 6 different variables is just going to be a world of pain. And when you need the grid to be 3x4 rather than 2x3, you'll regret that decision even more.
So, start with a completely blank form. And add, in the code, a two dimensional array of panels:
private
FPanels: array of array of TPanel;
Then, in the form's constructor, or an OnCreate event handler, you can initialise the array by calling a function like this:
procedure TMyForm.InitialisePanels(RowCount, ColCount: Integer);
var
Row, Col: Integer;
aLeft, aTop, aWidth, aHeight: Integer;
Panel: TPanel;
begin
SetLength(FPanels, RowCount, ColCount);
aTop := 0;
for Row := 0 to RowCount-1 do begin
aLeft := 0;
aHeight := (ClientHeight-aTop) div (RowCount-Row);
for Col := 0 to ColCount-1 do begin
Panel := TPanel.Create(Self);
FPanels[Row, Col] := Panel;
Panel.Parent := Self;
aWidth := (ClientWidth-aLeft) div (ColCount-Col);
Panel.SetBounds(aLeft, aTop, aWidth, aHeight);
inc(aLeft, aWidth);
end;
inc(aTop, aHeight);
end;
end;
And now you can refer to your panels using cartesian coordinates rather than a flat one dimensional array. Of course, you can easily enough declare a flat one dimensional array as well if you want.
The key idea is that when you are creating large numbers of control in a structured layout, you are best abandoning the designer and using code (loops and arrays).
Use FindComponent method of TComponent:
for variable := 1 to 6 do begin
pnl := FindComponent('Panel' + IntToStr(variable));
if pnl is TPanel then
begin
TPanel(pnl).Visible := true;
TPanel(pnl).Visible := false;
end;
end;
As others have answered, FindComponent is the way to go.
But if you just want to modify generic properties for the component, such as visible, position etc, it's not necessary to compare to the type.
This will work just as fine:
for i := 1 to 16 do
begin
(FindComponent( 'P' + inttostr(i) ) as TControl).Visible := false;
end;
(NOTE: this is for Delphi 6/ 7, modern versions probably do this in other ways)
Actually my answer
If you use a name convention to name your component like
"Mycomponent" + inttostr(global_int)
you can use it to find it very easily :
function getMyComponent(id:integer) : TComponent;
begin
result := {Owner.}FindConponent('MyComponent'+inttostr(id));
end;
You also can make your generated components to interact each other by using (sender as TComponent).name to know which other component are related to him.
Exemple
Following is an example of what you can do with this :
Imagine a pagecontrol where tabs are an interface you want to have multiple time
(for ex, to describe columns in a file with 1 tab = 1 col, and you want to dynamically add tabs).
For our example, we are naming button and edit this way :
Button : "C_(column_number)_btn"
Edit : "C_(column_number)_edi"
You can actually refer directly to the edit with a buttonclick, linked at runtime by calling findcomponent :
procedure TForm1.ColBtnClick(Sender:TObject);
var nr : string; Edit : TEdit;
begin
// Name of the TButton. C(col)_btn
nr := (Sender as TButton).Name;
// Name of the TEdit C_(column)_edi
nr := copy(nr,1,length(nr)-3)+'edi';
// Get the edit component.
edit := (Form1.Findcomponent(nr) as TEdit);
//play with it
Edit.Enabled := Not Edit.Enabled ;
showmessage(Edit.Text);
Edit.hint := 'this hint have been set by clicking on the button';
//...
end;
Of course, you link this procedure to every generated buttons.
If anyone wants to practice with it, you may want to know how to generate the tabsheet and components, here you go :
procedure Form1.addCol(idcol:integer, owner : TComponent); // Form1 is a great owner imo
var
pan : TPanel; // Will be align client with the new tabsheet
c: TComponent; //used to create components on the pannel
tab : TTabSheet;
begin
try
pan := TPanel.create(owner);
pan.name := format('Panel_%d',[idcol]);
pan.caption := '';
// dynamically create that button
c := TButton.create(Owner);
with c as TButton do
begin
Name := format('C%d_btn',[idcol]);
Parent := pan;
//Top := foo;
//Left := bar;
caption := 'press me';
OnClick := Form1.ColBtnClick; // <<<<<<< link procedure to event
end;
//create a Tedit the same way
c := TEdit.create(Owner);
with c as TEdit do
Name := format('C%d_edi',[idcol]);
Parent := pan;
// other properties
// create the tabsheet and put the panel in
finally
tab := TTabSheet.Create(Parent);
tab.caption := 'Column %d';
tab.PageControl := Pagecontrol1;
pan.Parent := tab;
pan.Align := alClient;
end;
end;
Generating names to get the component is actually a very good way to have a clean code.
Scrolling through parent - child components in order to find the one you want is actually inefficient and becomes hell if there is many component (in my example, if there is 3, 10 or unknown number of TEdit looping child (brother) components will be ugly.
Maybe this example is useless but It may helps someone, someday.