[4.2.0.265] Ext.Component: show() results in two layout runs if autoRender true

[GustavR]

REQUIRED INFORMATION
Ext version tested:

• Ext 4.1.2.1
• Ext 4.2.0.265

Description:

• When calling show() on a Ext.Component that has floating or autoRender its Layout is done twice!

Steps to reproduce the problem:

• Create Ext.window.Window
• Show it (using show())

The result that was expected:

• Layout is run once

The result that occurs instead:

• Layout is run twice

Test Case:

w = Ext.create('Ext.window.Window');

layoutCountBefore = w.layoutCounter;
        
w.show();
        
w.layoutCounter - layoutCountBefore; // 2

HELPFUL INFORMATION
Possible fix:

Ext.define('Ext.fix.Component', {
    override: 'Ext.Component',
    
    show: function(animateTarget, cb, scope) {
        var me = this,
            rendered = me.rendered;

        if (rendered && me.isVisible()) {
            if (me.toFrontOnShow && me.floating) {
                me.toFront();
            }
        } else {
            if (me.fireEvent('beforeshow', me) !== false) {
                // Render on first show if there is an autoRender config, or if this is a floater (Window, Menu, BoundList etc).
                me.hidden = false;
                if (!rendered && (me.autoRender || me.floating)) {
                    var autoRendered = true;
                    Ext.suspendLayouts();
                    me.doAutoRender();
                    rendered = me.rendered;
                    // there was no rendering done, so set autoRendered back to false and resume layouts
                    if (!rendered) {
                        autoRendered = false;
                        Ext.resumeLayouts();
                    }
                }
            
                if (rendered) {
                    me.beforeShow();
                    me.onShow.apply(me, arguments);
                    if (autoRendered) {
                        autoRendered = false;
                        Ext.resumeLayouts(true);
                    }
                    me.afterShow.apply(me, arguments);
                }
            } else {
                me.onShowVeto();
            }
        }
        return me;
    }
});

A smaller fix would be the following, but it has its downside that you have to use it everywhere you show a window:

w = Ext.create('Ext.window.Window');
Ext.suspendLayouts();
w.show();
Ext.resumeLayouts(true);
w.center();

[mitchellsimoens]

Thanks for the report! I have opened a bug in our bug tracker.