Buttons: add AltText

The same code is used once in widget toolkit and twice in PVE already,
so it makes sense to add it as a separate button.

Signed-off-by: Matthias Heiserer <m.heiserer@proxmox.com>
Reviewed-by: Dominik Csapak <d.csapak@proxmox.com>

src/Makefile

@@ -45,6 +45,7 @@ JSSRC=					\
 	form/ACME.js			\
 	form/UserSelector.js		\
 	button/Button.js		\
+	button/AltText.js		\
 	button/HelpButton.js		\
 	grid/ObjectGrid.js		\
 	grid/PendingObjectGrid.js	\

src/button/AltText.js

@@ -0,0 +1,22 @@
+Ext.define('Proxmox.button.AltText', {
+    extend: 'Proxmox.button.Button',
+    xtype: 'proxmoxAltTextButton',
+
+    defaultText: "",
+    altText: "",
+
+    listeners: {
+	// HACK: calculate the max button width on first render to avoid toolbar glitches
+	render: function(button) {
+	    let me = this;
+
+	    button.setText(me.altText);
+	    let altWidth = button.getSize().width;
+
+	    button.setText(me.defaultText);
+	    let defaultWidth = button.getSize().width;
+
+	    button.setWidth(defaultWidth > altWidth ? defaultWidth : altWidth);
+	},
+    },
+});