ColorInputField.java

/*
 * ******************************************************************************
 *  * Copyright 2015 See AUTHORS file.
 *  *
 *  * Licensed under the Apache License, Version 2.0 (the "License");
 *  * you may not use this file except in compliance with the License.
 *  * You may obtain a copy of the License at
 *  *
 *  *   http://www.apache.org/licenses/LICENSE-2.0
 *  *
 *  * Unless required by applicable law or agreed to in writing, software
 *  * distributed under the License is distributed on an "AS IS" BASIS,
 *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  * See the License for the specific language governing permissions and
 *  * limitations under the License.
 *  *****************************************************************************
 */

package com.commons.color;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Input;
import com.badlogic.gdx.scenes.scene2d.Actor;
import com.badlogic.gdx.scenes.scene2d.InputEvent;
import com.badlogic.gdx.scenes.scene2d.InputListener;
import com.badlogic.gdx.scenes.scene2d.utils.ChangeListener;
import com.badlogic.gdx.scenes.scene2d.utils.FocusListener;
import com.badlogic.gdx.scenes.scene2d.utils.UIUtils;
import com.kotcrab.vis.ui.InputValidator;
import com.kotcrab.vis.ui.widget.VisTextField;
import com.kotcrab.vis.ui.widget.VisValidatableTextField;


/**
 * Fields used to enter color numbers in color picker, verifies max allowed value
 * provides quick increment/decrement of current value by pressing [shift +] plus or minus on numpad
 * @author Kotcrab
 */
public class ColorInputField extends VisValidatableTextField {
    private int value;
    private int maxValue;

    public ColorInputField (final int maxValue, final ColorInputFieldListener listener) {
        super(new ColorFieldValidator(maxValue));
        this.value = 0;
        this.maxValue = maxValue;

        setProgrammaticChangeEvents(false);
        setMaxLength(3);
        setTextFieldFilter(new NumberFilter());

        addListener(new ChangeListener() {
            @Override
            public void changed (ChangeEvent event, Actor actor) {
                if (getText().length() > 0)
                    value = Integer.valueOf(getText());
            }
        });

		addListener(new InputListener() {
			@Override
			public boolean keyTyped (InputEvent event, char character) {
				ColorInputField field = (ColorInputField) event.getListenerActor();
				if (character == '+') field.changeValue(UIUtils.shift() ? 10 : 1);
				if (character == '-') field.changeValue(UIUtils.shift() ? -10 : -1);

                if (character != 0) listener.changed(getValue());

                return true;
            }
        });

        addListener(new FocusListener() {
            @Override
            public void keyboardFocusChanged (FocusEvent event, Actor actor, boolean focused) {
                if (focused == false && isInputValid() == false)
                    setValue(maxValue); //only possibility on invalid field is that entered value will be bigger than maxValue so we set field value to maxValue
            }
        });
    }

    public void changeValue (int byValue) {
        this.value += byValue;

        if (value > maxValue) value = maxValue;
        if (value < 0) value = 0;

        updateUI();
    }

    public int getValue () {
        return value;
    }

    public void setValue (int value) {
        this.value = value;
        updateUI();
    }

    private void updateUI () {
        setText(String.valueOf(value));
        setCursorPosition(getMaxLength());
    }

    interface ColorInputFieldListener {
        public void changed (int newValue);
    }

    private static class NumberFilter implements TextFieldFilter {
        @Override
        public boolean acceptChar (VisTextField textField, char c) {
            return Character.isDigit(c);
        }
    }

    private static class ColorFieldValidator implements InputValidator {
        private int maxValue;

        public ColorFieldValidator (int maxValue) {
            this.maxValue = maxValue;
        }

        @Override
        public boolean validateInput (String input) {
            if (input.equals("")) return false;

            Integer number = Integer.parseInt(input);
            if (number > maxValue) return false;

            return true;
        }
    }
}