WxSmith tutorial: Building more complex window
Building more complex window
Hi, in this tutorial I'll sow you some example of more complex window. Actually it would look complex when you start working with wxSmith. After writing few applications you will probably build few resources with this or even higher complexity so don't be scared. I'm working with wxSmith almost every day (it's really the best way to find bugs and discover nice improovements and that's what I should do as it's creator ;)) and athough edition may look comlex at the beginning, it's not hard to get used to it.
I also want you to know that as I'm writing the beginning of this tutorial, I'm also beginning of writing the application - I didn't prepared ready solution since I would like to show process of creating window in really natural way (maybe even with some mistakes), so while writing the tutorial I'll also create the application.
We will start with empty frame - if you've read previous tutorials you shouold create one without problems.
First task - some basic concept
My proposition for exmple application would be something to manage colleciton of CD-roms. So at the beginning we should realize what should be presented at the main window. Let's say that we would have most informations at the main window (although it may not be a very good assumption, it would help to show creation of more complex resources).
I would like to have some list of CD-roms on the left and some details of selected CD-rom on the right. So basically we have two regions in our window: one with the list and one with the details. I'd like also to use sizers because the application should be cross-platform and main window should be resizable.
We also want the application to look nice on both windows and linux. If you remember the first tutorial, we had to add extra wxPanel into frame to make the background better so let's to the same thing here:
- First add wxBoxSizer directly into resource
- Add wxPanel into that sizer
- Set size of border to 0 to make the panel cover entine window
Now we should have some this result:
Now let's add wxBoxSizer into it - this sizer will manage out two main regions. After that the tree structure should look like this:
Now we can start filling those two regions - each one may have only one item (so the sizer we've just added will manage them). Usually in such sutiatuion I use wxStaticBoxSizer because we can mark regions and put some name for them. So let's add two wxStaticBoxSizer-s into the window. Be carefull while adding the second one because you may add it into the first region - always remember that parent for new items is always the item totally covered with blue:
To add second sizer properly you must click on the border surrounding the first one just like on the picture. Note that now the resource is small but it will change when we will add some items into regions.
Ok, now let's add some item which will show list of CDs. We can use wxListBox here:
The list is rather small so let's resize it using drag-boxes to something bigger and higher:
Ok, but the second sizer did not resize. That's right since we didn't turn on it's Expand' flag. To do this let's click on the second sizer and check it's Expand property:
Now we can change labels of regions since they are fully visible now. To do this click on each region's sizer and change the Label property:
Ok but we would like to have ability to add and delete selected cd - we will insert two buttons for this purpose in the first region. To add the button choose it from palette and add into the sizer. Note that we can now point wxListBox item - it can not have children so wxSmith will try to add new item before or after it. After adding button we would have such result:
Hmm, the button should be under the list, not next to it. wxStaticBoxSizer did align items as it should - by default it aligns them in horizontal line. To change the direction to vertical, you can change the Orientation property of wxStaticBoxSizer. But before we change it let's predict one more thing. I would like to have two buttons instead of only one and I'd like them to be aligned horizontally. Since wxStaticBox will be changed to vertical mode, we will have to use another sizer used only for buttons. So let's add wxBoxSizer right after the list and before button:
Now let's change Orientation of the wxStaticBoxSizer to vertical. After changing we have following result:
We can see that something's wrong here. The wxBoxSizer is abnormally stretched and if we scroll the editor we can see that the same goes to button. We said in previous tutorial that wxBoxSizer an wxStaticBoxSizer are trying to keep same size of items in one direction - that's what happened here. wxStaticBoxSizer used the highest item (list of CDs) and applied this height into all managed items. How to disable it? By setting Proportion property of both wxBoxSizer and wxButton to 0. This will notify that those items shouldn't be used in height calculations:
Now let's move the button into the wxBoxSizer - you can very easily do it by clickong on the button and dragging it into the sizer. After that we can add second button next to the first one:
Nowe we can see that the list don't have Expand property set (otherwise it would be almost as wide as the region.
Now I'd like to see how current work does look in the application. We could simply run it (F9) or by pressing the preview button on the right part of wxSmith editor:
(If you run application you will see that there's menu and statusbar, on the preview it won't show, wxSmith still misses few features ;) )
Our window looks good, not perfect but let's leave some polishing for later and fill the CD details region.
Inside CD details I'd like to have description of CD:
- Type (Music/Program/Backup/Other)
- Date of release
For such list we would need some grid sizer. Ok, but the region has wxStaticBoxSizer which align items only in one line. To overcome this limitation we can just add another sizer into wxStaticBoxSizer and use new one as the grid. From two available sizers I suggest wxFlexGridSizer (wxGridSizer would force all cells to have same size which wouldn't look good because row with description may need some more space than others). So let's add new sizer:
- Add wxFlexGridSizer into wxStaticBoxSizer
- Check Expand property of new item
- Set Border Size to 0 to avoid some unwanted border.
Data presented here should be shown in two columns - first for the label and second for value so let's change the Cols property to 2. And now it's time to add the content. For labels we will use wxStaticText and for the value we will use different items:
- wxChoice for Type
- wxTextCtrl for Title, Artist/Author and Description
- wxDatePickerCtrl for Date of release
After adding items we should have following view:
Hmm, as I've said at the beginning - I didn't prepared anything before writing this tutorial. And guess what. It looks like wxDatePickerCtrl is broken on linux and sometimes crashes C::B (I didn't check on windows), don't know yet whether it's in wxWidgets or wxSmith - I'll have to investigate it. So we will have to change wxDatePickerCtrl to something else or remove it.
There's alternative for wxDatePickerCtrl - wxCallendarCtrl so first let's try to replace wxDatePickerCtrl. First we will have to remove wrong item (by using 'delete' key or by pressing 'X' button on the right side of the editor). After the change we can see that generated callendar is quite but according to other items in this region. We can shrink it a little bit by checking wxCAL_SEQUENTIAL_MONTH_SELECTION inside the Style property but it will make the item harder to navigate. We can additionally set wxSUNKEN_BORDER style to add some nice border around the callendar. Ok, not perfect but acceptable ;)
Now we have this screen:
Ok, it looks like we have few things to do now:
- First is to check Expand property for the first region since (it didn't expand when the second region increased height)
- Second is to set proper labels for values if CD details region
- Third thing is to adjust items used to edit values in CD details region
First two tasks are quite easy and I leave them to you :)
Third task will require few new things so I'll describe it better: