org.rstudio.core.client.widget.TextBoxWithCue.java Source code

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Here is the source code for org.rstudio.core.client.widget.TextBoxWithCue.java

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/*
 * TextBoxWithCue.java
 *
 * Copyright (C) 2009-12 by RStudio, Inc.
 *
 * Unless you have received this program directly from RStudio pursuant
 * to the terms of a commercial license agreement with RStudio, then
 * this program is licensed to you under the terms of version 3 of the
 * GNU Affero General Public License. This program is distributed WITHOUT
 * ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING THOSE OF NON-INFRINGEMENT,
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Please refer to the
 * AGPL (http://www.gnu.org/licenses/agpl-3.0.txt) for more details.
 *
 */
package org.rstudio.core.client.widget;

import com.google.gwt.dom.client.Element;
import com.google.gwt.event.dom.client.BlurEvent;
import com.google.gwt.event.dom.client.BlurHandler;
import com.google.gwt.event.dom.client.FocusEvent;
import com.google.gwt.event.dom.client.FocusHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.TextBox;
import org.rstudio.core.client.StringUtil;
import org.rstudio.core.client.dom.DomUtils;
import org.rstudio.core.client.dom.WindowEx;

public class TextBoxWithCue extends TextBox {
    public TextBoxWithCue() {
        this("");
    }

    public TextBoxWithCue(String cueText) {
        cueText_ = cueText;
        getElement().setAttribute("spellcheck", "false");
    }

    public TextBoxWithCue(String cueText, Element element) {
        super(element);
        cueText_ = cueText;
        element.setAttribute("spellcheck", "false");
    }

    public String getCueText() {
        return cueText_;
    }

    public void setCueText(String cueText) {
        cueText_ = cueText;
    }

    @Override
    public String getText() {
        return isCueMode() ? "" : super.getText();
    }

    @Override
    protected void onAttach() {
        super.onAttach();
        if (!StringUtil.isNullOrEmpty(cueText_))
            hookEvents();
    }

    @Override
    protected void onDetach() {
        super.onDetach();
        unhookEvents();
    }

    private void hookEvents() {
        unhookEvents();

        FocusHandler focusHandler = new FocusHandler() {
            public void onFocus(FocusEvent event) {
                if (DomUtils.hasFocus(getElement())) {
                    if (isCueMode()) {
                        setText("");
                        removeStyleName(CUE_STYLE);
                    }
                }
            }
        };

        BlurHandler blurHandler = new BlurHandler() {
            public void onBlur(BlurEvent event) {
                if (getText().length() == 0) {
                    addStyleName(CUE_STYLE);
                    setText(cueText_);
                }
            }
        };

        registrations_ = new HandlerRegistration[] { addFocusHandler(focusHandler), addBlurHandler(blurHandler),
                WindowEx.addFocusHandler(focusHandler), WindowEx.addBlurHandler(blurHandler) };

        blurHandler.onBlur(null);
    }

    private boolean isCueMode() {
        return (getStyleName() + " ").indexOf(CUE_STYLE + " ") >= 0;
    }

    private void unhookEvents() {
        if (registrations_ != null) {
            for (HandlerRegistration reg : registrations_)
                reg.removeHandler();
            registrations_ = null;
        }
    }

    private String cueText_;
    private final String CUE_STYLE = "cueText";
    private HandlerRegistration[] registrations_;
}