WxSmith tutorial: Keyboard Input and Displaying Results - Revision history

Cyuyan: /* Getting Input from the User and Handling the Items List in a Combobox */

2024-02-17T00:59:39Z

Getting Input from the User and Handling the Items List in a Combobox

Grouch at 23:55, 11 August 2016

2016-08-11T23:55:26Z

Aganel: /* Getting Input from the User and Handling the Items List in a Combobox */ Added а paragraph about wxTE_PROCESS_ENTER

2014-04-18T17:50:55Z

Getting Input from the User and Handling the Items List in a Combobox: Added а paragraph about wxTE_PROCESS_ENTER

Grouch: End of edits to make printg() global.

2012-09-05T22:34:39Z

End of edits to make printg() global.

Grouch: The first of several edits to make printg() a friend, not a member, of the interface class, so that it can be called easily from anywhere.

2012-09-05T20:47:04Z

The first of several edits to make printg() a friend, not a member, of the interface class, so that it can be called easily from anywhere.

Grouch: /* Tutorial 9. Keyboard Input and Displaying Results */

2012-07-11T19:53:44Z

Tutorial 9. Keyboard Input and Displaying Results

Alpha: Added navigation.

2012-03-17T21:34:59Z

Added navigation.

Alpha: Added filenames to code sections.

2012-03-12T01:13:35Z

Added filenames to code sections.

Alpha: Syntax highlighting.

2012-03-10T00:13:40Z

Syntax highlighting.

Show changes

Alpha: Fixed catagory link.

2012-03-05T01:22:20Z

Fixed catagory link.

@@ Line 58: / Line 58: @@
 ''Tutorial_9Main.cpp''
-<source lang="cpp" enclose="div" line start="129">
+<source lang="cpp" enclose="div" line="1" start="129">
 void printg(char *fmt, ...);
-void wxSmithTuts_Tutorial_9Frame::OnMirandaBtnClick(wxCommandEvent& event)
+void Tutorial_9Frame::OnButton1Click(wxCommandEvent& event)
+{
      printg("%s","O brave new world!\n");

← Older revision		Revision as of 23:55, 11 August 2016
Line 366:		Line 366:

	<center>'''[[WxSmith tutorial: Drawing on the Screen and Saving Drawings\|Previous]] \| [[WxSmith tutorials\|Index]]'''</center>		<center>'''[[WxSmith tutorial: Drawing on the Screen and Saving Drawings\|Previous]] \| [[WxSmith tutorials\|Index]]'''</center>
		+	[[Tutorial 10. Using wxGrid]]

← Older revision		Revision as of 17:50, 18 April 2014
Line 330:		Line 330:

	For the moment, we will comment out the call to “anything()”, so that we can compile, run and test the program at this point. Try it!		For the moment, we will comment out the call to “anything()”, so that we can compile, run and test the program at this point. Try it!
		+
		+	You may notice that nothing happens when you press Enter in CmdBox. That is because we have to set CmdBox to handle that event. Select this control in Code::Blocks Resources window, then in Properties open Style section and check wxTE_PROCESS_ENTER. Now it's working as expected.

	The function ''anything()'', however, is important. It is where the real work of the program gets done. It looks at what the user has put in ''inbuf'' and decides what to do. That may be to run a regression or to calculate a comet's orbit, or to do anything computers can do. Our ''inbuf'' was declared globally, so if ''anything()'' does not use ''printg()'', it does not need to be a member of the class we have been building, But most likely it does use ''printg()'' – and ''printg()'' has to be a member of the class because it uses ''Results'' – so ''anything()'' has to be a member of the class.		The function ''anything()'', however, is important. It is where the real work of the program gets done. It looks at what the user has put in ''inbuf'' and decides what to do. That may be to run a regression or to calculate a comet's orbit, or to do anything computers can do. Our ''inbuf'' was declared globally, so if ''anything()'' does not use ''printg()'', it does not need to be a member of the class we have been building, But most likely it does use ''printg()'' – and ''printg()'' has to be a member of the class because it uses ''Results'' – so ''anything()'' has to be a member of the class.

@@ Line 109: / Line 109: @@
 Now we encounter a new hurdle. Our ''printout'' contains a normal C-string, but to display it in the wxTextCtrl, we have to convert it to a wxString.  Fortunately, wxWidgets gives us a one-line solution to that problem:
-<source lang="cpp" enclose="div" line start="159">
+<source lang="cpp" enclose="div" line start="163">
          wxString POwx(printout, wxConvUTF8);
 </source>
@@ Line 117: / Line 117: @@
 Now that we have our wxString, we can append it to the Results member of the TextCtrl by the line
-<source lang="cpp" enclose="div" line start="160">
+<source lang="cpp" enclose="div" line start="164">
-         Results->AppendText(POwx);
+         MainFrame->Results->AppendText(POwx);
 </source>
 Finally, we set ''printout'''s length to 0 by the line

@@ Line 28: / Line 28: @@
 Give the Combo box the name CmdBox (for Command Box) and give the TextCtrl the name Results.
-Now we go into new territory. Open the file Tutorial_9Main.h (Use File | Open … to do so.) and add printg to its public members as shown here.
+Now we go into new territory. Open the file Tutorial_9Main.h (Use File | Open … to do so.) and add printg as a friend of the class, as shown here.
 ''Tutorial_9Main.h''
@@ Line 36: / Line 36: @@
          Tutorial_9Frame(wxWindow* parent,wxWindowID id = -1);
          virtual ~Tutorial_9Frame();
-         void printg(char *fmt, ...);
+         friend void printg(char *fmt, ...);
      private:
 </source>
 Save and close that file. Double click on “Test printg” button. The file Tutorial_9Main.cpp opens and you find the frame for OnButton1Click and fill it in as follows:
@@ Line 55: / Line 57: @@
 ''Tutorial_9Main.cpp''
-void Tutorial_9Frame::printg(char *fmt, ...)
+<source lang="cpp" enclose="div" line start="129">
+{
      char buf[240];
      va_list args;
@@ Line 69: / Line 83: @@
      lenb = strlen(buf);
      lenp = strlen(printout);
-     if(lenb+lenp >= 238)
+     if(lenb+lenp >= MAXPRINTOUT-2){
          wxString wxPO(printout, wxConvUTF8);
-         Results->AppendText(wxPO);
+         MainFrame->Results->AppendText(wxPO);
          printout[0] = '\0';
-−
+        }
      strcat(printout, buf);
      lenp = strlen(printout);
-     // If the last character in printout is \n, then it is time to print
+     // If the last character in printout is \n, then it is time to
-     if(printout[lenp-1] == '\n')
+    // print
      if(printout[lenp-1] == '\n'){
          // convert printout to a wxString, which we will call wxPO
          wxString wxPO(printout, wxConvUTF8);
-         Results->AppendText(wxPO);
+         MainFrame->Results->AppendText(wxPO);
          printout[0] = '\0';
-−
+        }
-−
+     }
 </source>

@@ Line 25: / Line 25: @@
 [[Image:9a.png]]
-By now, you can probably create such a form in your sleep, but to be sure we are together, in the form's property browser you give it the Title property “Terminal-like Interface”, then you put a box sizer on the form, and in the sizer put a panel and check the panel's Expand property. On the panel put a box sizer and in its properties make it vertical. Into it drop successively a button, a Combo box, and a TextCtrl. Give the button the label “Test printg”. Mark the Expand property of the Combo Box and check its Style property Process_Enter. On the TextCtrl, uncheck Default size, and make it 300 wide and 200 high. Mark its Expand property, and drop down the Style properties and check AutoScroll, Multiline, and Full_Repaint_On_Resize.
+By now, you can probably create such a form in your sleep, but to be sure we are together, in the form's property browser you give it the Title property “Terminal-like Interface”, then you put a box sizer on the form, and in the sizer put a panel and check the panel's Expand property. On the panel put a box sizer and in its properties make it vertical. Into it drop successively a button, a Combo box, and a TextCtrl. Give the button the label “Test printg” and make is Proportion property 0. Mark the Expand property of the Combo Box and make its Proportion property 0. On the TextCtrl, uncheck Default size, and make it 300 wide and 200 high. Mark its Expand property, and drop down the Style properties and check AutoScroll, Multiline, and Full_Repaint_On_Resize.
 Give the Combo box the name CmdBox (for Command Box) and give the TextCtrl the name Results.
@@ Line 98: / Line 98: @@
 </source>
-This line declares POwx as a variable of type wxString and initializes it by converting our C-string, printout, to the UTF-8 representation of the string and stores that string in a variable of the type wxString. (''POwx'' is just a name I made up to suggest printout transformed to a wxString. You could replace it with ''abcd'' or whatever. UTF-8 –  Universal character set Transformation Format, 8 bit – is a variable-width encoding that can represent every Unicode character.)
+This line declares POwx as a variable of type wxString and initializes it by converting our C-string, printout, to the UTF-8 representation of the string and stores that string in a variable of the type wxString. (''POwx'' is just a name I made up to suggest printout transformed to a wxString. You could replace it with ''abcd'' or whatever. (UTF-8 stands for  Universal character set Transformation Format, 8 bit. It is a variable-width encoding that can represent every Unicode character.)
 Now that we have our wxString, we can append it to the Results member of the TextCtrl by the line

@@ Line 276: / Line 276: @@
 </source>
-so when we type something in the combobox and tap Enter, we should see what we wrote appear twice on Results, once as before and once preceeded by the words “Anything says:” But we must not forget to put ''anything()'' into the definition of the class. So over in the Tutorial_9Main.h file we need to add a line as indicated here:
+so when we type something in the combobox and tap Enter, we should see what we wrote appear twice on Results, once as before and once preceded by the words “Anything says:” But we must not forget to put ''anything()'' into the definition of the class. So over in the Tutorial_9Main.h file we need to add a line as indicated here:
 ''Tutorial_9Main.h''
@@ Line 293: / Line 293: @@
 Maybe that seems like not much, but remember that ''anything()'' has infinite potential.

@@ Line 30: / Line 30: @@
 Now we go into new territory. Open the file Tutorial_9Main.h (Use File | Open … to do so.) and add printg to its public members as shown here.
 <source lang="cpp" enclose="div" line start="26" highlight="5">
      public:
@@ Line 42: / Line 43: @@
 Save and close that file. Double click on “Test printg” button. The file Tutorial_9Main.cpp opens and you find the frame for OnButton1Click and fill it in as follows:
 <source lang="cpp" enclose="div" line start="129" highlight="3">
 void Tutorial_9Frame::OnButton1Click(wxCommandEvent& event)
@@ Line 52: / Line 54: @@
 Just below it, you can now put this definition of the character arrays ''printout'' and ''inbuf'' and the function ''printg()''.
 <source lang="cpp" enclose="div" line start="134">
 char printout[240], inbuf[240];
@@ Line 119: / Line 122: @@
 In the Code::Blocks editor, open the file Tutorial_9Main.cpp if it is not already open. At the bottom, put the lines
 <source lang="cpp" enclose="div" line start="165">
 void Tutorial_9Frame::OnCreate(wxWindowCreateEvent& event)
@@ Line 132: / Line 136: @@
 You might think this were enough, but it isn't quite so simple. If we stopped with just this code, it would never get executed. We also have to open the file Tutorial_9Main.h and add several lines. First, around line 39 or 40 you should find the first two of the following three lines.
 <source lang="cpp" enclose="div" line start="36" highlight="4">
          void OnAbout(wxCommandEvent& event);
@@ Line 150: / Line 155: @@
 somewhere – anywhere, it seems  – among the members in the class definition in the Tutorial_9Main.h file (newer versions of wxSmith may have already auto-generated this line). We may as well put it at the end, so that we get something like this
 <source lang="cpp" enclose="div" highlight="23">
 class Tutorial_9Frame: public wxFrame
@@ Line 181: / Line 187: @@
 The Event Table itself, however, is back in the Tutorial_9Main.cpp file. wxSmith did not use the event table but it marked the place for it (at about line 55) by two comments. When we put it between these comments we get this:
 <source lang="cpp" enclose="div" line start="54" highlight="4">
 BEGIN_EVENT_TABLE(Tutorial_9Frame,wxFrame)
@@ Line 199: / Line 206: @@
 To get started, click on the combobox in the Code::Blocks Resources window. Then click on the {} icon in the top line of the Properties browser, so that it becomes the Events browser. Double-click the EVT_TEXT_ENTER event. This event occurs when the user has entered some text in the combobox and taps Enter. WxSmith will create the frame for us . Here is that frame and the code that needs to go in it..
 <source lang="cpp" enclose="div" line start="172">
 void Tutorial_9Frame::OnCmdBoxTextEnter(wxCommandEvent& event)
@@ Line 260: / Line 268: @@
 We will write anything() as simply
 <source lang="cpp" enclose="div" line start="186">
 void Tutorial_9Frame::anything()
@@ Line 269: / Line 278: @@
 so when we type something in the combobox and tap Enter, we should see what we wrote appear twice on Results, once as before and once preceeded by the words “Anything says:” But we must not forget to put ''anything()'' into the definition of the class. So over in the Tutorial_9Main.h file we need to add a line as indicated here:
 <source lang="cpp" enclose="div" line start="26" highlight="6">
      public:

← Older revision		Revision as of 01:22, 5 March 2012
Line 1:		Line 1:
−	[[wxSmith Documentation]]	+	[[Category:wxSmith Documentation]]
	=Tutorial 9. Keyboard Input and Displaying Results=		=Tutorial 9. Keyboard Input and Displaying Results=