dash-to-panel/panelStyle.js

/*
 * This file is part of the Dash-To-Panel extension for Gnome 3
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Credits:
 * The code for recursing child actors and assigning inline styles
 * is based on code from the StatusAreaHorizontalSpacing extension
 * https://bitbucket.org/mathematicalcoffee/status-area-horizontal-spacing-gnome-shell-extension
 * mathematical.coffee@gmail.com
 */

const Me = imports.misc.extensionUtils.getCurrentExtension();
const ExtensionUtils = imports.misc.extensionUtils;
const Lang = imports.lang;
const Main = imports.ui.main;
const Mainloop = imports.mainloop;
const St = imports.gi.St;
const Shell = imports.gi.Shell;

const TaskBar = Me.imports.taskbar;

const taskbarPanelStyle = new Lang.Class({
    Name: 'TaskBar.PanelStyle',

    _init: function(settings) {
        this._dtpSettings = settings;
    },

    enable : function(panel) {
        this.panel = panel;

        this._applyStyles();

        //this._bindSettingsChanges();
    },

    disable: function () {
        this._removeStyles();
    },

    _bindSettingsChanges: function() {
        /* whenever the settings get changed, re-layout everything. */
        [
            "leftbox-padding",
            "tray-padding",
            "status-icon-padding"
        ].forEach(function(configName) { // fix foreach
            settings.connect('changed::' + configName, Lang.bind(this, function () {
                this._removeStyles();
                this._applyStyles();
            }));
        });
    },

    _applyStyles: function() {
        this._rightBoxOperations = [];
        
        let trayPadding = -1; //this._dtpSettings.get_int('tray-padding');
        if(trayPadding >= 0) {
            let trayPaddingStyleLine = '-natural-hpadding: %dpx'.format(trayPadding);
            if (trayPadding < 6) {
                trayPaddingStyleLine += '; -minimum-hpadding: %dpx'.format(trayPadding);
            }
            let operation = {};
            operation.compareFn = function (actor) {
                return (actor.has_style_class_name && actor.has_style_class_name('panel-button'));
            };
            operation.applyFn = Lang.bind(this, function (actor) {
                global.log('applying ' + trayPaddingStyleLine + ' to ' + actor.get_style_class_name());
                this._overrideStyle(actor, trayPaddingStyleLine);
            });
            this._rightBoxOperations.push(operation);
        }

        let statusIconPadding = -1; //this._dtpSettings.get_int('status-icon-padding');
        if(statusIconPadding >= 0) {
            let statusIconPaddingStyleLine = 'padding-left: %dpx; padding-right: %dpx'.format(statusIconPadding, statusIconPadding)
            let operation = {};
            operation.compareFn = function (actor) {
                return (actor.has_style_class_name && actor.has_style_class_name('system-status-icon'));
            };
            operation.applyFn = Lang.bind(this, function (actor) {
                this._overrideStyle(actor, statusIconPaddingStyleLine);
            });
            this._rightBoxOperations.push(operation);
        }
       
        // center box has been moved next to the right box and will be treated the same
        this._centerBoxOperations = this._rightBoxOperations;

        this._leftBoxOperations = [];

        let leftboxPadding = -1; //this._dtpSettings.get_int('leftbox-padding');
        if(leftboxPadding >= 0) {
            let leftboxPaddingStyleLine = '-natural-hpadding: %dpx'.format(leftboxPadding);
            if (leftboxPadding < 6) {
                leftboxPaddingStyleLine += '; -minimum-hpadding: %dpx'.format(leftboxPadding);
            }
            let operation = {};
            operation.compareFn = function (actor) {
                return (actor.has_style_class_name && actor.has_style_class_name('panel-button'));
            };
            operation.applyFn = Lang.bind(this, function (actor) {
                this._overrideStyle(actor, leftboxPaddingStyleLine);
            });
            this._leftBoxOperations.push(operation);
        }

        if(this._rightBoxOperations.length) {
            let children = this.panel._rightBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._rightBoxOperations);
        }

        if(this._centerBoxOperations.length) {
            let children = this.panel._centerBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._centerBoxOperations);
        }

        if(this._leftBoxOperations.length) {
            let children = this.panel._leftBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._leftBoxOperations);
        }
        
        /* connect signal */
        this._rightBoxActorAddedID = this.panel._rightBox.connect('actor-added',
            Lang.bind(this, function (container, actor) {
                if(this._rightBoxOperations.length)
                    this._recursiveApply(child, this._rightBoxOperations);
            })
        );
        this._centerBoxActorAddedID = this.panel._centerBox.connect('actor-added',
            Lang.bind(this, function (container, actor) {
                if(this._centerBoxOperations.length)
                    this._recursiveApply(child, this._centerBoxOperations);
            })
        );
        this._leftBoxActorAddedID = this.panel._leftBox.connect('actor-added',
            Lang.bind(this, function (container, actor) {
                if(this._leftBoxOperations.length)
                    this._recursiveApply(child, this._leftBoxOperations);
            })
        );
    },

    _removeStyles: function() {
        /* disconnect signal */
        if (this._rightBoxActorAddedID) 
            this.panel._rightBox.disconnect(this._rightBoxActorAddedID);
        if (this._centerBoxActorAddedID) 
            this.panel._centerBox.disconnect(this._centerBoxActorAddedID);
        if (this._leftBoxActorAddedID) 
            this.panel._leftBox.disconnect(this._leftBoxActorAddedID);

        if(this._rightBoxOperations.length) {
            let children = this.panel._rightBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._rightBoxOperations, true);
        }

        if(this._centerBoxOperations.length) {
            let children = this.panel._centerBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._centerBoxOperations, true);
        }

        if(this._leftBoxOperations.length) {
            let children = this.panel._leftBox.get_children();
            for(let i in children)
                this._recursiveApply(children[i], this._leftBoxOperations, true);
        }
    },

    _recursiveApply: function(actor, operations, restore) {
        for(let i in operations) {
            let o = operations[i];
            if(o.compareFn(actor))
                if(restore)
                    o.restoreFn ? o.restoreFn(actor) : this._restoreOriginalStyle(actor);
                else
                    o.applyFn(actor);
        }

        if(actor.get_children) {
            let children = actor.get_children();
            for(let i in children) {
                this._recursiveApply(children[i], operations, restore);
            }
        }
    },
    
    _overrideStyle: function(actor, styleLine) {
        if (actor._original_inline_style_ === undefined) {
            actor._original_inline_style_ = actor.get_style();
        }

        actor.set_style(styleLine + '; ' + (actor._original_inline_style_ || ''));
        actor._dtp_line_style = styleLine;
 
        /* listen for the style being set externally so we can re-apply our style */
        // TODO: somehow throttle the number of calls to this - add a timeout with
        // a flag?
        if (!actor._dtpPanelStyleSignalID) {
            actor._dtpPanelStyleSignalID =
                actor.connect('style-changed', Lang.bind(this, function () {
                    let currStyle = actor.get_style();
                    if (currStyle && !currStyle.match(actor._dtp_line_style)) {
                        // re-save the style (if it has in fact changed)
                        actor._original_inline_style_ = currStyle;
                        // have to do this or else the overrideStyle call will trigger
                        // another call of this, firing an endless series of these signals.
                        // TODO: a ._style_pending which prevents it rather than disconnect/connect?
                        actor.disconnect(actor._dtpPanelStyleSignalID);
                        delete actor._dtpPanelStyleSignalID;
                        this._overrideStyle(actor, styleLine);
                    }
                }));
        }
    },

    _restoreOriginalStyle: function(actor) {
        if (actor._dtpPanelStyleSignalID) {
            actor.disconnect(actor._dtpPanelStyleSignalID);
            delete actor._dtpPanelStyleSignalID;
        }
        if (actor._original_inline_style_ !== undefined) {
            actor.set_style(actor._original_inline_style_);
            delete actor._original_inline_style_;
            delete actor._dtp_line_style;
        }
    }
    
});