Gestures

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Gesture Types

There are 8 types of gestures:

• IR.GESTURE_SWIPE_LEFT
• IR.GESTURE_SWIPE_RIGHT
• IR.GESTURE_SWIPE_UP
• IR.GESTURE_SWIPE_DOWN
• IR.GESTURE_PINCH_IN
• IR.GESTURE_PINCH_OUT
• IR.GESTURE_LONG_PRESS
• IR.GESTURE_DOUBLE_TAP

Activating Gestures

To use gestures in iRidium you should activated them. To activate gestures us the command:

IR.AddRecognizer(Gesture_Type);

Example of activating gestures at the application launch:

IR.AddListener(IR.EVENT_START,0,function()  // Event is activated at the application launch
{
    IR.AddRecognizer(IR.GESTURE_SWIPE_LEFT);  // Activate gesture SWIPE_LEFT
    IR.AddRecognizer(IR.GESTURE_SWIPE_RIGHT); // Activate gesture SWIPE_RIGHT
    IR.AddRecognizer(IR.GESTURE_SWIPE_UP);    // Activate gesture SWIPE_UP
    IR.AddRecognizer(IR.GESTURE_SWIPE_DOWN);  // Activate gesture SWIPE_DOWN
});

Activated gestures work until the application is working or until they are deactivated. If some gesture is already activated its reactivation is to the detriment of system resources.

Deactivating Gestures

If the activated gesture is not required any more it can be deactivated. To deactivate gestures use the command:

IR.RemoveRecognizer(Gesture_Type);

Example of deactivating gestures when exiting the application:

IR.AddListener(IR.EVENT_EXIT,0,function()  // Event is activated when exiting the application
{
    IR.RemoveRecognizer(IR.GESTURE_SWIPE_LEFT);  // Deactivate gesture SWIPE_LEFT
    IR.RemoveRecognizer(IR.GESTURE_SWIPE_RIGHT); // Deactivate gesture SWIPE_RIGHT
    IR.RemoveRecognizer(IR.GESTURE_SWIPE_UP);    // Deactivate gesture SWIPE_UP
    IR.RemoveRecognizer(IR.GESTURE_SWIPE_DOWN);  // Deactivate gesture SWIPE_DOWN
});

Processing Gestures

The following event is responsible for gesture processing:

IR.EVENT_GESTURE_BEGIN

To process gestures connect IR.AddListener, the event is sent to it:

IR.AddListener(IR.EVENT_GESTURE_BEGIN, Page_Name, function(gesture, x, y){Function_Body});

Gesturs are processed on pages only. Each page requires connection of a separate Listener To process gestures for a particular page you are required to send its name to Listener - Page_Name.
To receive data about gestures Listener receives the function with parameters:

• gesture - the variable stores the gesture type;
• x - the variable stores x-coordinate of gesture start;
• y - the variable stores y-coordinate of gesture start;

To describe commands for each gestures it is convenient to use the choice structure.

Example of gesture processing:

var button; 
IR.AddListener(IR.EVENT_START, 0, function()  // Event is activated at the application launch
{
    // Create a button for switching pages 
    var button = IR.CreateItem(IR.ITEM_BUTTON, "text", 10, 10);
    button.Text = "";
     
    // Activating gestures
    IR.AddRecognizer(IR.GESTURE_SWIPE_LEFT);  // Activate gesture SWIPE_LEFT
    IR.AddRecognizer(IR.GESTURE_SWIPE_RIGHT); // Activate gesture SWIPE_RIGHT
    IR.AddRecognizer(IR.GESTURE_SWIPE_UP);    // Activate gesture SWIPE_UP
    IR.AddRecognizer(IR.GESTURE_SWIPE_DOWN);  // Activate gesture SWIPE_DOWN

    // Connect Listener, send the current page and the function with parameters.
    IR.AddListener(IR.EVENT_GESTURE_BEGIN, IR.CurrentPage, function(gesture, x, y)
    {
        
        // Choice structure
        switch(gesture)
        {
        case IR.GESTURE_SWIPE_LEFT: 
            button.Text = "Left";   // If you start a gesture SWIPE_LEFT you see the sign "Left"
            break;
        case IR.GESTURE_SWIPE_RIGHT:
            button.Text = "Right";  // If you start a gesture SWIPE_RIGHT you see the sign "Right"
            break;
        case IR.GESTURE_SWIPE_UP:
            button.Text = "Up";     // If you start a gesture SWIPE_UP you see the sign "Up"
            break;
        case IR.GESTURE_SWIPE_DOWN:
            button.Text = "Down";   // If you start a gesture SWIPE_DOWN you see the sign "Down"
            break;
        }
    });
});

Working with Gesture Areas

If it gestures are required to work only in a particular area on the screen use parameters x and y which store coordinates of gesture start. You can describe any area on the screen using these coordinates and calculations.

As and example let's describe a half of iPad screen and activate gestures in the described area only:

var button; 
IR.AddListener(IR.EVENT_START, 0, function()  // Event is activated at the application launch
{
    // Create a button for switching pages
    var button = IR.CreateItem(IR.ITEM_BUTTON, "text", 10, 10);
    button.Text = "";
      
    // Activating gestures
    IR.AddRecognizer(IR.GESTURE_SWIPE_LEFT);  // Activate gesture SWIPE_LEFT
    IR.AddRecognizer(IR.GESTURE_SWIPE_RIGHT); // Activate gesture SWIPE_RIGHT
    IR.AddRecognizer(IR.GESTURE_SWIPE_UP);    // Activate gesture SWIPE_UP
    IR.AddRecognizer(IR.GESTURE_SWIPE_DOWN);  // Activate gesture SWIPE_DOWN
 
    // Connect Listener, send the current page and the function with parameters.
    IR.AddListener(IR.EVENT_GESTURE_BEGIN, IR.CurrentPage, function(gesture, x, y)
    {
     // The width of iPad is 1024 pixels, 512 is a half
     if (x <= 512) // If the gesture start equals or is less than a half of the screen
     { 
        // Choice sructure
        switch(gesture)
        {
         case IR.GESTURE_SWIPE_LEFT: 
            button.Text = "Left";   // If you start a gesture SWIPE_LEFT you see the sign "Left"
            break;
        case IR.GESTURE_SWIPE_RIGHT:
            button.Text = "Right";  // If you start a gesture SWIPE_RIGHT you see the sign "Right"
            break;
        case IR.GESTURE_SWIPE_UP:
            button.Text = "Up";     // If you start a gesture SWIPE_UP you see the sign "Up"
            break;
        case IR.GESTURE_SWIPE_DOWN:
            button.Text = "Down";   // If you start a gesture SWIPE_DOWN you see the sign "Down"
            break;
        }
     }
    });
});