JTK – Notes and Ramblings Things we have found …

I did the automatic update to WordPress 5.4 last night and things got weird. The editor was causing php errors. The browser page appeared blank but turning on developer tools showed there was a pile of stuff including a message to look at https://wordpress.org/support/article/debugging-in-wordpress/

Time to turn on debugging by adding this bit to wp/wp-config.php:

// Enable WP_DEBUG mode
define( 'WP_DEBUG', true );

// Enable Debug logging to the /wp-content/debug.log file
define( 'WP_DEBUG_LOG', true );

// Enable display of errors and warnings
define( 'WP_DEBUG_DISPLAY', true );
@ini_set( 'display_errors', 0 );

// Use dev versions of core JS and CSS files (only needed if you are modifying these core files)
define( 'SCRIPT_DEBUG', true );

This revealed several errors and warnings. The primary one was solved by removing an ancient but in theory up to date plug-in for Movable Type and TypePad import.

The remaining errors were: register_sidebar was called incorrectly. No id was set in the arguments array for the "Sidebar 1" sidebar. Defaulting to "sidebar-1". Manually set the id to "sidebar-1" to silence this notice and keep existing sidebar content. causing several Cannot modify header information - headers already sent by (output started at /home/taing/jtkdev.com/wp/wp-includes/functions.php:5167) in /home/taing/jtkdev.com/wp/wp-includes/functions.php on line 6221

In looking at wp-content/themes/classic/functions.php there is very little there. By removing the block below the error messages are gone and the pages seem to display correctly:

if ( function_exists('register_sidebar') )
        register_sidebar(array(
                'before_widget' => '<li id="%1$s" class="widget %2$s">',
                'after_widget' => '</li>',
                'before_title' => '',
                'after_title' => '',
        ));

This is why having the source code and a bit of Google is awesome. I was unable to get my Microchip PICkit3 to work on an Acer Switch 5 with Windows 10 when using the Microchip standalone PICkit3 application. The PICkit3 worked on my Windows 7 HP laptop or on the Acer with MPLAB X 5.10 but refused to connect in the standalone application. After a bit of googling about for the issue and many false leads I found https://www.microchip.com/forums/m908976.aspx.

The issue seems to be a a loop in the USB.Find_This_Device () function that is too short. After reading the thread I attempted to connect the PICkit3 with the Acer keyboard disconnected and was successful each time. This supported the theory.

Fortunately the source for the standalone application is included in the package. After downloading and installing Visual Studio Express 17 I was able to follow along with the steps in the discussion.

I opened PICkit2V2.sln from PICkit3 Programmer Application Source v3.10/PICkit2V2 in Visual Studio. After finding the file USB.cs and changing line 203 to read:

for (int l_loop = 0; l_loop < 64; l_loop++)

I was able to rebuild, resulting in a new PICkit3.exe. For more context the surrounding code is:

MyDeviceInterfaceData.cbSize = Marshal.SizeOf(MyDeviceInterfaceData);
for (int l_loop = 0; l_loop < 64; l_loop++)
{
Result = SetupDiEnumDeviceInterfaces(
DeviceInfoSet,
0,
ref HidGuid,
l_loop,
ref MyDeviceInterfaceData);
if (Result != 0)
{

https://css-tricks.com/debouncing-throttling-explained-examples/ pointed me to http://unscriptable.com/2009/03/20/debouncing-javascript-methods/.

If you are already using jQuery, underscore.js or Lodash you have versions of this in your framework. The simplest version not embedded in a library or framework which doesn’t use prototypes was:

 
var debounce = function (func, threshold, execAsap) {
    var timeout;
    return function debounced () {
        var obj = this, args = arguments;
        function delayed () {
            if (!execAsap)
                func.apply(obj, args);
            timeout = null;
        };
        if (timeout)
            clearTimeout(timeout);
        else if (execAsap)
            func.apply(obj, args);
        timeout = setTimeout(delayed, threshold || 100)
    };
} 

func is the function to call, threshold is the interval expressed in milliseconds and execAsap determines if the function is called at the beginning or end of the interval. The function will only be called once per interval.

 
document.onmousemove = debounce(function (e) {
    /* do something here, but only once after mouse cursor stops */ 
}, 250, false);