REAL Software Forums

OK. Here's what I want to do, but I can't figure out how to do it.

I want to have a rectangle with text in it on the screen, and I want the user to be able to click on the rectangle with the mouse and drag the rectangle to another location, with the rectangle and text visible during the dragging.

I've tried various combinations of MouseDown, MouseDrag (and MouseMove), and MouseUp with various controls, but I haven't found anything yet that really works.

(StaticText perhaps comes closest, but (1) the control disappears while it is being moved, and I want it to stay visible, and (2) I want the rectangle to have a border, and StaticText doesn't.)

Any advice (or, even better, information on where I can find sample code that shows how to do this)?

Barry Traver

Barry

One approach would be to create a Picture image from the rect with the text in it, and draw that to the window during the drag event.

Should work fine, there's an example in the Examples folder look for Drag and Drop.

You can set the drag object's preview image via declares or plugins. Or fake it using a semi-transparent window and a timer (for tracking the mouse), and then fire the drag code at the end (when the user releases the mouse).

Jordan,


Thanks for the sugggestions.


Actually, the DrawPics demo in the Graphics subfolder of the Examples folder is _very_ close to what I want. I even figured out how to modify it so that the ovals contain words instead of letters of the alphabet. My problem is that I do not understand graphics code at all. Yes, I can move the ovals, but I can's figure out how to find out the text that they contain. (It would have been nice if it I could distinguish between the ovals in a simple way - e.g., Pic(1).Text = "For" - but it's not that simple.)

With most code, I can figure out what most of the lines are doing, but with graphicss code I don't have the slightest idea what most of the lines are doing.


True, but if we have the same sample program in mind, it doesn't show how to drag a control, but how to drag text (e.g., a line from a ListBox) from a control to a different control, and that's not what I want to do.

I do know how to write the code so that a person can click on a control (e.g., a PushButton) and then click on the location desired for that control and the control will immediately go to that location, but that is not as "intuitive" for the user, even though it is simple to write, merely changing properties of the control, e.g. through code like this:


Any additional advice?

Barry Traver

P.S. The intent of the program is to give the user a quotation where the word order is scrambled and the user has to put the words in the correct order.

Did you want to drag a control (ie. pushbutton) or text that is part of an editfield?

Not sure which. For a control, you can simply capture the mousedown event and then in the MouseMove event have the control's coordinate (top, left) track with the MouseMove's (X and Y). This will move the control until the MouseUp event is detected. Of course in the MouseUp you'd position the moved control exactly where you'd like it to appear.

If you want to move text as part of an editfield (Roughly the steps are):

0. Starting with a MouseDown event.
1. You'd first have to determine which word the mouse is currently on using editfield.selStart
2. Highlight the word
3. create a Picture image, draw the highlighted text to the picture's graphic property.
4. draw this to the screen while Mouse is still down. While the Mouse is still down, update the window, refreshing only the part of the window that is being affected by the dragged picture.
5. In the MouseUp event, you'd insert/place the new text, and remove the highlighted text from the original location.

Sounds more complicated than it really is.

I've thrown together a quick canvas subclass that does something similar with dragged text at http://rb.sgarman.net/sjgTextBox.rbp which may give you some clues as to how to start.

Steve,

Thanks as I saved it myself as I can use all the help I can.

Steve,

Thanks! Your code is exactly what I was looking for!

Even though at this point I don't understand what you did (I still haven't figured out how classes and subclasses work <sigh>), I have experimented enough with modifying your code so that I am able to use it as a basis to do what I want to do (i.e., know which control is being moved and to what location).

Here's a "quick and dirty" way to modify your program to test whether "Hello," "Beautiful," and "World" are in the correct order, left to right:

(The test is made upon each MouseUp for the three textBox controls.)

Just curious: I notice that your textBox controls have event procedures for MouseEnter, Mouse Exit, MouseMove, MouseUp, and MouseWheel, but not MouseDown. I can get along without it, but is there a reason for the absence of MouseDown?

Barry Traver

I'll try to knock together a blow-by-blow description of creating this immensely simple subclass later, but first I'll deal with the question with the shorter answer.

Only that I didn't bother to create an event handler.

The sjgTextBox control is a subclass of Canvas and automatically exposes the canvas events that I haven't used.

However, I have code in MouseDown, MouseDrag and Paint of the subclass, so I would need to create and call an event handler for each of them if I wanted to make them available in the subclass.

Not very polished but it's up at rbjottings.blogspot.com

I'm told that at least one version of RB gives memory problems with so I've changed the sample to use

Steve,

This is just a "thank you" for the help. Not only does your sample code provide what I needed to write my program, but also it provides a concrete example of subclassing that should get me closer to understanding how classes and subclasses work.

Barry

I'm still working on understanding classes, subclasses, etc. (although I've printed out the related chapter from the RB User's Guide), but the other thing I need to know (besides how to drag a control) for a REALbasic program I'm working on is how to add new controls while the RB program is running.

How is this done when you're using classes, subclasses, etc., using the approach at http://rb.sgarman.net/sjgTextBox.rbp ?

Barry Traver

Jordan,

You said this:


The problem I'm running into is this: When I click on the control, the X and Y I get for MouseDown anf MouseMove is the position on the control, NOT the position in the Window. (And when I then move the mouse with the mouse down, X and Y don't change.) (Also when I click on the control, MouseDown, MouseMove, and MouseUp for the Window do not fire.)

I'm probably missing something simple, but I can't seem to get a normal drag of a control working.

Barry Traver

In the MouseDown event of a control put:
In the Window's Open event put:
In the Window's DropObject event put:
Good luck!
-Jailout2000