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SetOnKey

JS Py

Hello World

You can use SetOnKey for receiving and handling all key events fired in the application.

app.SetOnKey( callback )

You may want to use it with DisableKeys - i.e. for defining a custom ENTER command for automatic control focussing.

You can find the complete list of keys and their codes on the Android Developer Page.

See Also: SimulateKey

Example - Demonstration

app.DisableKeys( 'VOLUME_DOWN,VOLUME_UP,BACK' );

function OnStart()
{
    lay = app.CreateLayout( "linear", "VCenter,FillXY" );

    txt = app.CreateText( "", -1, -1, "multiline,left,monospace" );
    lay.AddChild( txt );

    edt = app.CreateTextEdit( "", .8, .1 );
    lay.AddChild( edt );

    app.AddLayout( lay );

    app.SetOnKey( OnKey );

    edt.Focus();
    app.ShowKeyboard( edt )
    edt.Gone();
}

function OnKey(action, name, code, extra) {
    var text =
        "action:" + action +
        "\nname :" + name +
        "\ncode :" + code +
        "\nextra :" + extra;

    txt.SetText( text );
}

from native import app

app.DisableKeys( "VOLUME_DOWN,VOLUME_UP,BACK" )

def OnStart():
    global txt
    lay = app.CreateLayout( "linear", "VCenter,FillXY" )

    txt = app.CreateText( "", -1, -1, "multiline,left,monospace" )
    lay.AddChild( txt )

    edt = app.CreateTextEdit( "", .8, .1 )
    lay.AddChild( edt )

    app.AddLayout( lay )

    app.SetOnKey( OnKey )

    edt.Focus()
    app.ShowKeyboard( edt )
    edt.Gone()

def OnKey(action, name, code, extra):
    text = "action:" + action + "\nname :" + name + "\ncode :" + code + "\nextra :" + extra
    txt.SetText( text )

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Example - Surprise

var prev;

function OnStart()
{
    app.DisableKeys( "VOLUME_DOWN,VOLUME_UP" );
    app.ShowPopup( "Press the volume keys!" );

    lay = app.CreateLayout( "Linear", "FillX" );
    lay.SetPadding( 0, .85 );
    lay.Hide();

    img = app.CreateImage( "/Sys/Img/Hello.png", -1, .3 );
    lay.AddChild( img );

    app.AddLayout( lay );

    app.SetOnKey( OnKey );
}

function OnKey(action, name, code, extra)
{
    if( action != prev ) {
        if( action == "Down" ) lay.Animate( "SlideFromBottom", null, 300 );
        if( action == "Up" ) lay.Animate( "SlideToBottom" , null, 300 );
    }
    prev = action;
}

from native import app

prev

def OnStart():
    global lay
    app.DisableKeys( "VOLUME_DOWN,VOLUME_UP" )
    app.ShowPopup( "Press the volume keys!" )

    lay = app.CreateLayout( "Linear", "FillX" )
    lay.SetPadding( 0, .85 )
    lay.Hide()

    img = app.CreateImage( "/Sys/Img/Hello.png", -1, .3 )
    lay.AddChild( img )

    app.AddLayout( lay )

    app.SetOnKey( OnKey )

def OnKey(action, name, code, extra):
    if action != prev:
        if action == "Down":
            lay.Animate( "SlideFromBottom", None, 300 )
        if action == "Up":
            lay.Animate( "SlideToBottom", None, 300 )
    prev = action

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function( action, name, keycode, extrakeys )