https://github.com/mabe02/lanterna: Java library for creating text-based terminal GUIs
  • Martin Berglund 
/*
 * This file is part of lanterna (http://code.google.com/p/lanterna/).
 * 
 * lanterna is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * Copyright (C) 2010-2020 Martin Berglund
 */
package com.googlecode.lanterna.gui2;

import com.googlecode.lanterna.TerminalSize;


This interface defines a renderer for a component, an external class that does the sizing and rendering. All
components will have a default renderer defined, which can usually be overridden manually and swapped out for a
different renderer, but also themes can contain renderer definitions which are automatically assigned to their
associated components.

Author:Martin
Type parameters:
  • <T> – Type of the component which this renderer is designed for
/**
 * This interface defines a renderer for a component, an external class that does the sizing and rendering. All
 * components will have a default renderer defined, which can usually be overridden manually and swapped out for a
 * different renderer, but also themes can contain renderer definitions which are automatically assigned to their
 * associated components.
 * @param <T> Type of the component which this renderer is designed for
 * @author Martin
 */
public interface ComponentRenderer<T extends Component> {
    
Given the supplied component, how large does this renderer want the component to be? Notice that this is the
responsibility of the renderer and not the component itself, since the component has no idea what its visual
representation looks like.

Params:
  • component – Component to calculate the preferred size of
Returns:The size this renderer would like the component to take up
/**
     * Given the supplied component, how large does this renderer want the component to be? Notice that this is the
     * responsibility of the renderer and not the component itself, since the component has no idea what its visual
     * representation looks like.
     * @param component Component to calculate the preferred size of
     * @return The size this renderer would like the component to take up
     */
    TerminalSize getPreferredSize(T component);

    
Using the supplied graphics object, draws the component passed in.

Params:
  • graphics – Graphics object to use for drawing
  • component – Component to draw
/**
     * Using the supplied graphics object, draws the component passed in.
     * @param graphics Graphics object to use for drawing
     * @param component Component to draw
     */
    void drawComponent(TextGUIGraphics graphics, T component);
}