PtContainerHold, PtContainerRelease

Arguments

Returns

t if successful.

Description

PtContainerHold prevents the updating of contents of the widget. PtContainerRelease allows updating to continue.

Successive calls to PtContainerHold increment a counter. An equal number of calls to PtContainerRelease are required to decrement the counter so the widget can be updated.

Example

This example, ex_PtContainerHold.g, is included in the gamma_ph_#_examples_1_QNX4.tgz file available on the Cogent Web Site.

#!/usr/cogent/bin/phgamma

/*  This sample program puts two panes in a window.
    Each pane contains a label that is updated every
    second by a timer.  A button toggles the Held and
    Released state for each pane.
*/

require_lisp("PhotonWidgets");
PtInit(nil);
win=new(PtWindow);

class_add_ivar(PtPane,#held,nil);

but1 = new(PtButton);
but1.text_string = "Released";
but1.SetPos(20,40);

but2 = new(PtButton);
but2.text_string = "Released";
but2.SetPos(20,140);

pane1 = new(PtPane);
pane1.fill_color = PgRGB(160,160,160);
pane1.SetArea(100,0,200,100);

time1 = new(PtLabel);
time1.text_string = date();

PtSetParentWidget(win);
pane2 = new(PtPane);
pane2.fill_color = PgRGB(220,220,220);
pane2.SetArea(100,100,200,100);

time2 = new(PtLabel);
time2.text_string = date();

every(1,#time1.text_string = date());
every(1,#time2.text_string = date());

function toggle_hold (pane)
{
  if (pane.held)
  {
    PtContainerRelease(pane);
    pane.held = nil;
    widget.text_string = "Released";
  }
  else
  {
    PtContainerHold(pane);
    pane.held = t;
    widget.text_string = "Held";
  }
}

PtAttachCallback(but1,Pt_CB_RAW,#toggle_hold(pane1),Ph_EV_BUT_PRESS);
PtAttachCallback(but2,Pt_CB_RAW,#toggle_hold(pane2),Ph_EV_BUT_PRESS);

PtRealizeWidget(win);

PtMainLoop();
 
		

See Also

In Photon documentation: PtContainerRelease, PtContainerHold.