Make Components In TpageControl Available To Only One Page - delphi

I am starting on my first application using delphi (using delphi XE 2) and I'm trying to piece my way through creating the GUI right now.
I'm trying to use a TpageControl to keep things separated and simple but when I try to place a component on a tabsheet it shows on all of them. According to what I have read the components placed on each given tab are only supposed to show in that one.
Basically I want each tab to operate as a separate form. Does anyone have any tips and/or tutorials on working with the Tpagecontrol in order to do what I have described?
Thanks.

Just have a look at the structure and you will see why this happens.
Button1 and Button2 seems to be related to TabSheet1, but looking at the structure you will see, that the parent of Button1 is Form1 and the parent of Button2 is TabSheet1.
If you switch to TabSheet2 Button1 is still visible, but Button2 is not.
But you can drag drop the controls within the structure panel from actual parent to a new parent.

Related

MDI interface with FireMonkey

Is it possible to create an MDI application using FireMonkey in a traditional sense of many documents forms/frames and one master form?
I'm specifically interested since there are no MDI controls on forms anymore.. Has it been replaced with something different?
EDIT: Adding to the question, when I create child forms they all showed separately in taskbar, even the OpenDialogs..
Here's one approach you can use:
1) Create your individual forms as normal, except use a TLayout, call it "LayoutMain", (aligned alClient) as the parent of all controls on that form.
2) On your "master form", when you want to bring a form instance in to behave as it would as an MDI interface, create a TLayout (call it "FormContainer" or something), place as a child of that (aligned to top) another TLayout (call it "FormHeader"), containing the individual controls for the Form Caption, the Minimize/Maximize/Close buttons and anything else you'd like on the "frame" heading. This is called a Composite.
3) Create an instance of your child form (but don't show it), then parent that instance's primary TLayout "LayoutMain" to your main form's TLayout "FormContainer".
4) On the TLayout previously mentioned (with the name "FormHeader"), give it OnMouseDown and OnMouseMove events to provide the ability to drag it around the Master Form.
When you want to maximize the child form inside the master form, you'd just set the outer TLayout "FormContainer" align property to alClient, remembering to store its original Top, Left, Width and Height values within the the form's instance so you can recall them when pressing the Restore button.
True, this is a fairly involved solution, but to the very best of my knowledge this is the only way you're going to achieve what you're trying to do with FireMonkey as it exists today (circa Update 2).
I wouldn't expect Embarcadero to provide any form of MDI emulation as part of FireMonkey "out of the box", as MDI is considered an old-fashioned approach.
The more modern solution would be to use Docking, as the RAD Studio IDE itself does. This provides the very best of both worlds, giving the user the freedom to choose what child forms they want to link into the master form, or display outside of that on their own (or any combination of docked arrangements).

Duplicate ControlBox

I have inherited an application that was started as an MDI program, but the necessary background work was never put in place to fully support MDI. I'm trying to build in just enough MDI support to make the application look good and work properly as an SDI application.
Here's what I am observing, and I don't know how this is happening or how to fix it.
The MDIchild form's border is shown above the MDIparent form's menu strip.
The MDIchild form has two icons in the upper left.
The MDIchild form has two ControlBoxes in the upper right.
Any ideas why this would be?
I'd be really happy if the MDIChild window border (including the icons and control boxes) was removed entirely.
Thanks,
SH
I created the child form but showed it in normal state instead of maximized. It's as if showing the parent form in the same process as the maximized child form caused the form to be constructed out of order. My code looked something like this...
frmChild.WindowState = FormWindowState.Normal
frmParent.Show() 'frmChild.Show called within form_load of parent
frmChild.WindowState = FormWindowState.Maximized
And yes, I set the Child window's FormBorderStyle to None, but like I said, I didn't want an MDI application.
I think this must be a bug in Visual Studio. For so many people to have difficulty with it, it can't be right.
I found:
Call Show() on your MDI form before setting the WindowState property on your child form to get rid of the multiple control boxes.
Do not set the WindowState to Maximized in the designer -- do it in code after you've shown the parent.

Delphi - Duplicate tpanel and tbuttons on second form

On my main form I have a TPanel containing buttons that act as a toolbar. I want to clone/copy this toolbar and the buttons and their functionality to a second form.
Cloning the menu was simple using newmenu.merge(mainmenu). That was an excellent shortcut to duplicating a Tmainmenu.
But I am at a loss on how to easily duplicate my toolbar without having to manually assign the events and keep a timer to compare and track which buttons are enabled and disabled in comparison to the real mainmenu on the main form. Depending on what the application is doing the main toolbar buttons will be enabled and disabled at various times.
Any ideas here? Thanks for any suggestions or tips to make this easier.
Duplicating the controls
In the Form Designer, select the panel and press Ctrl+C to copy it and all its children to the clipboard. Go to the second form and press Ctrl+V to paste.
If you're still working on the design and want to keep it consistent between both forms, then create a TFrame and design your toolbar layout there. Then put an instance of that frame on both your forms. Changes to the frame design will be reflected in the forms.
See Working with frames in the help.
Making sure both sets of buttons are enabled consistently
Create a data module. Put a TActionList on it. Add an action to it for each button on your main form. Assign event handlers to the actions' OnUpdate events. In them, set the actions' Enabled properties. Finally, assign each button's Action property to refer to the corresponding action object. The buttons will automatically get enabled and disabled with the actions. No timer required.
Furthermore, you can handle the actions' OnExecute events, too. Clear each button's OnClick property, and then move the button's OnClick code into the corresponding action's OnExecute handler. It will automatically get called when you click the button, even though the OnClick property is empty.
When you assign the Caption or Hint property of a TAction, the corresponding properties of any associated controls also change. Likewise for images, if the control supports them. Actions can be assigned to menu items, too.
See Using action lists in the help.
Acting like a toolbar
Just use TToolbar. That's what it's for.
Or, once you're used to actions, put a TActionManager in your project and use it with TActionToolbar and TActionMainMenuBar. See Organizing actions for toolbars and menus in the help.
Are the buttons attached to actions? If so, you can use the OnUpdate event of the TActionList to specify what should and should not be enabled. If not, it isn't too much work to convert to using actions.
If you go this route to convert to using a ActionList, consider putting the ActionList in a datamodule where different units and forms could reference it.
You can Use ClipBoard Object For Copy Your Panel.
Clipboard.SetComponent(Panel1);
Clipboard.GetComponent(Form2,GroupBox1);

Design-time drag and drop in Delphi?

Before Delphi 2006 (I think) introduced the TFlowPanel and TGridPanel, I did a control that was similar in concept. It still does a couple of things those controls do not do, and when upgrading my code to Delphi 2009, I decided to add a couple of enhancements to that as well.
Right now, the order of the child controls is determined by their creation order. The FlowPanel and GridPanel show a better way with ControlIndex and other filtered properties, but I was wondering if there is a way to handle drag and drop reordering in design-time? As far as I can tell, dragging an edit control and dropping it onto my panel doesn't call anything that I can access at design-time.
I was half-fantasising about a way to either detect the drop operation directly, or to perhaps detect when a control is moved so I can determine where it should go.
Any ideas?
Update:
OK, got it working. The container control was already overriding AlignControls to manage the placement of the controls. When you drag the nested control and drop it, AlignControls is again called. I then compared the new coordinates of the control with the other controls in the list and moved it to the appropriate position.
There were a couple of problems that I had to work through (mostly related to the many calls to AlignControls) but the basic concept is simple enough. Thanks to all the commenters for all the help.
You can't drag a control that's already on the form and drop it onto your panel. Dragging is only for moving a control, not for changing its parent. To change the parent, cut and paste.
If the control is already on your panel, and you want to move it to another position on your panel, then the panel can control the layout by overriding the TWinControl.AlignControls method. When a control is moved, its SetBounds method is called, and among the things tha happens is that it calls AlignControl(Self) on its parent window. That calls AlignControls. Look in Controls.pas, and you'll see that that's a complicated method, but it's what is responsible for the layout of the children on a control, and that's exactly what you're planning to change.
Perhaps some of these suggestions might help.
You can re-parent a control in the designer without having to do cut-and-paste. View the structure pane, and simply drag the visual control to the node of another parent in the structure pane. If you have things in a flowpanel, drag everything out of the flow panel and drag them back in the order that you want them to be.
(You can re-parent ANY visual control this way, without changing anything other than its parent. I highly recommend doing it this way.)
You can view the form as text, and move the declaration order around in there -- but obviously you'll need to be careful when editing the "resource" file directly.
You can set tab order in the designer, so you could make a different control based on tab order that works as you want. You can right click on the form and change the creation order of the non-visual controls, but that doesn't work with visual controls.
Have you tried to write an "OnDragDrop" event for your grid component, where you check if your component is in design mode?
I haven't written such a component yet, but I don't see why the event shouldn't trigger.

Delphi control that could mimic "Add-ons|Extension list" of Firefox?

My aim is to update the look of the GUI in my app. Currently my GUI contains a lot of listboxes which are used to edit some objects in an old fashioned way, that is, user double-clicks an item and a dialog is shown to modify the corresponding object.
I think a good modern approach is how Firefox displays the extensions installed (a snapshot below).
My question is about how to build such a GUI in Delphi(win32) easily? Are there any components you use mimicing such behaviour or will I just need to code this from stratch using panels? (IMO a very cumbersome job I'd like to avoid - the selection logic, resizings, etc...)
You can do something similar (not exactly) with standard components; TDBCtrlGrid, TSpeedButton,...
alt text http://img8.imageshack.us/img8/9585/imagen29ox3.png
If you're using Delphi 2007 or Delphi 2009, you might be able to do something similar using TCategoryButtons (from the 'Additional' component palette page). Drop it on a form and right click to display the popup menu, and then click "Categories Editor...". Add a category with the resulting dialog, set it's caption, and optionally set up Items it contains. Not exactly the same, but it might do what you need.
You could also use a dialog with a TTreeView (if you have categories of objects) or TListView to emulate the Delphi 2007 Projects->Options dialog. Clicking an item in the TreeView or ListView displays the proper page of a TPageControl to configure the object.
I mostly agree with Lars, but I would use a frame for each item instead of a panel. That would separate into its own file, and you would get easy designtime support for it.
Using a TFrame for each list item and put them all Aligned Top on a TScrollBox might work. Also see TDBCtrlGrid which does something like that in combination with datasets.
It can be done with existing Delphi controls.
For instance in the TCustomListBox control you can create your own OnDrawItem event to draw your own list item. You also need to create your own OnMeasureItem to change the item height.
In some cases it is very limited, so if you want more freedom you will need to do it from scratch.

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