Enigma1 THE BIBLE - Lesson7: Combobox -优快云博客

Lesson7: Combobox

/*
+--------------------------------------------------------------------------
| The Bible Enigma1 Tutorial
| ========================================
| By: Bacicciosat aka Meo aka Luponero
|
| Enigma 1 API GUI tutorial with Sources Code and Comments
| (c) august 2006 by Meo
|
+---------------------------------------------------------------------------
*/

Lesson7: Combobox

You can find in attach:
- the cfg file (Bibledemo.cfg)
- the compiled and working plugin (Bibledemo.so)
- the source file (bibledemo.cpp)
- the makefile (nedeed to compile code if you want to modify source)

Ok this is the lesson number seven.
We will add to our Window a Combobox and a messagebox to show the item of the list we have selected.
You can see the example in the screenshot.

You can test this application simply uploading in your dreambox (/var/tuxbox/plugins) the files that you can find in attach: Bibledemo.cfg and Bibledemo.so

You can modify this application editing the source file bibledemo.cpp and recompiling it to have a new Bibledemo.so file.

The Enigma API we will explain in this lesson is the Combobox creation.
These are only a part of the listbox API. The Combobox is more complicated and it is a box containing a Listbox so we will examine here only the main calls:

Code:

// create Combobox
eComboBox(eWidget* parent, int OpenEntries=5, eLabel* desc=0, int takefocus=1, const char *deco="eComboBox" );
// Functions:
int setCurrent( int, bool=false );

// Listbox items:
//create new item:
eListBoxEntryText(eListBox<eListBoxEntryText>* lb, const char* txt=0, void *key=0, int align=0, const eString &hlptxt="", int keytype = value );
// retrieve selected item
getCurrent()->getText();
// retrieve selected key
getCurrent()->getKey()

Ok now that we have listed the main API we can write the code.
You can find the complete application code in the attach package
(bibledemo.cpp). Here i will comment only the code added in this
lesson.

Let's go.

bibledemo.cpp additions:

First of all we have to add to our include files the Enigma Combobox library.

Code:

#include <lib/gui/combobox.h>

Ok Now we have to add the declaration of Combobox in our main class.
We have to add a function too:
void message1();
we will connect the execution of this function to a button.
In this way when the button is pushed this function will be called and it will show the Combobox item we have selected.
This is our new main class declaration:

Code:

// The Class declaration of our Main Window
class eBibleMainWindow: public eWindow
{
    // the label to show the text
    eLabel *label;
    // the listbox
    eListBox<eListBoxEntryText> *theList;
    // the combobox
    eComboBox *Lang;
    // function to execute whwn button is pushed
    void message1();
public:
        // the constructor.
    eBibleMainWindow();
        // the destructor.
    ~eBibleMainWindow();
};

Perfect !! Now we have to add the Combobox and populate it with items. We have also to add a button and to connect it
to the function that will show a messagebox:

Code:

eBibleMainWindow::eBibleMainWindow(): eWindow(1)
{
        // move our dialog to 100.100...
    cmove(ePoint(100, 100));
        // ...and give x and y dimensions.
    cresize(eSize(520, 376));
        // set a title.
    setText("Enigma Bible Lesson 7: Combobox");
    
    // create a label to show a text.
    label=new eLabel(this);
    // give a position
    label->move(ePoint(50, 50));
    // set the label dimensions
    label->resize(eSize(400, 60));
    // set the label text
    label->setText("Select your language");

    // Create the Combobox
    Lang=new eComboBox(this, 4);
    // Populate the Combobox with a List of Items
    new eListBoxEntryText(*Lang, "English", (void *) (0));
    new eListBoxEntryText(*Lang, "French", (void *) (1));
    new eListBoxEntryText(*Lang, "Italian", (void *) (2));
    new eListBoxEntryText(*Lang, "Dutch", (void *) (3));
    // set Combobox position
    Lang->move(ePoint(50, 160));
    // Combo dimensions
    Lang->resize(eSize(clientrect.width()-120, 35));
    // set the default entry of Combobox to the first element of the list
    Lang->setCurrent(0);
    // decore Combo with a frame
    Lang->loadDeco();
    
    // create button and set properties
    eButton * ok = new eButton(this);
    ok->setText("Show");
    ok->move(ePoint((clientrect.width() - 90)/2, clientrect.height() - 60));
    ok->resize(eSize(100, 40));
    ok->setShortcut("green");
    ok->setShortcutPixmap("green");
    ok->loadDeco();
    
    // function to call when button is pushed
    CONNECT(ok->selected, eBibleMainWindow::message1);
    // set focus to the Combobox
    setFocus(Lang);

}

Finally we have to add the function that will show the MessageBox with the selected item:

Code:

void eBibleMainWindow::message1()
{
    // declare variable we will use in this function
    eString message, message2;
    // assign to message2 the selected item text
    message2 = Lang->getCurrent()->getText();
    // compose message concatenating strings
    message = "Your Language is:/n " + message2;    
    // Create, show and execute the messagebox to display the message
    eMessageBox msg((message), "Info", eMessageBox::iconInfo|eMessageBox::btOK);
        msg.show();
        msg.exec();
        msg.hide();
}

As you can see is very simply.
You can now exercise to compile source you find in the attach package and to modify it.

Exercises:
- Retrieve the item key instead of the item text

That's all, and this is the application shot and the complete package.
(to be continued in lesson 8 ... )

Attached Images