Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package com.ocado.rangeui.client.gui.component.grid.column; import com.google.gwt.cell.client.AbstractEditableCell; import com.google.gwt.cell.client.Cell.Context; import com.google.gwt.cell.client.ValueUpdater; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Element; import com.google.gwt.dom.client.EventTarget; import com.google.gwt.dom.client.InputElement; import com.google.gwt.dom.client.NativeEvent; import com.google.gwt.event.dom.client.KeyCodes; import com.google.gwt.i18n.client.NumberFormat; import com.google.gwt.safehtml.client.SafeHtmlTemplates; import com.google.gwt.safehtml.shared.SafeHtml; import com.google.gwt.safehtml.shared.SafeHtmlBuilder; import com.google.gwt.text.shared.SafeHtmlRenderer; import com.google.gwt.text.shared.SimpleSafeHtmlRenderer; import static java.lang.Integer.parseInt; /** * * @author zhan */ public class EditNumberCell extends AbstractEditableCell<Number, EditNumberCell.ViewData> { private final NumberFormat format; // private Number Number(String value) { // throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates. // } interface Template extends SafeHtmlTemplates { @Template("<input type=\"text\" value=\"{0}\" tabindex=\"-1\"></input>") SafeHtml input(String value); } static class ViewData { private boolean isEditing; /** * If true, this is not the first edit. */ private boolean isEditingAgain; /** * Keep track of the original value at the start of the edit, which might be * the edited value from the previous edit and NOT the actual value. */ private Number original; private Number num; /** * Construct a new ViewData in editing mode. * * @param num the Number to edit */ public ViewData(Number num) { this.original = num; this.num = num; this.isEditing = true; this.isEditingAgain = false; } @Override public boolean equals(Object o) { if (o == null) { return false; } ViewData vd = (ViewData) o; return equalsOrBothNull(original, vd.original) && equalsOrBothNull(num, vd.num) && isEditing == vd.isEditing && isEditingAgain == vd.isEditingAgain; } public Number getOriginal() { return original; } public Number getNumber() { return num; } @Override public int hashCode() { return original.hashCode() + num.hashCode() + Boolean.valueOf(isEditing).hashCode() * 29 + Boolean.valueOf(isEditingAgain).hashCode(); } public boolean isEditing() { return isEditing; } public boolean isEditingAgain() { return isEditingAgain; } public void setEditing(boolean isEditing) { boolean wasEditing = this.isEditing; this.isEditing = isEditing; // This is a subsequent edit, so start from where we left off. if (!wasEditing && isEditing) { isEditingAgain = true; original = num; } } public void setNumber(Number num) { this.num = num; } private boolean equalsOrBothNull(Object o1, Object o2) { return (o1 == null) ? o2 == null : o1.equals(o2); } } private static Template template; private final SafeHtmlRenderer<String> renderer; /** * Construct a new EditTextCell that will use a * {@link SimpleSafeHtmlRenderer}. */ public EditNumberCell() { this(NumberFormat.getDecimalFormat(), SimpleSafeHtmlRenderer.getInstance()); } public EditNumberCell(NumberFormat format) { this(format, SimpleSafeHtmlRenderer.getInstance()); } /** * Construct a new EditTextCell that will use a given {@link SafeHtmlRenderer} * to render the value when not in edit mode. * * @param renderer * @return */ // public EditNumberCell(NumberFormat format, SafeHtmlRenderer<String> renderer) { // super("click", "keyup", "keydown", "blur"); // if (template == null) { // template = GWT.create(Template.class); // } // if (format == null) { // throw new IllegalArgumentException("format == null"); // } // if (renderer == null) { // throw new IllegalArgumentException("renderer == null"); // } // this.format = format; // this.renderer = renderer; // } public EditNumberCell(SafeHtmlRenderer<String> renderer) { this(NumberFormat.getDecimalFormat(), renderer); } @Override public boolean isEditing(Context context, Element parent, Number value) { ViewData viewData = getViewData(context.getKey()); return viewData == null ? false : viewData.isEditing();//To change body of generated methods, choose Tools | Templates. } public EditNumberCell(NumberFormat format, SafeHtmlRenderer<String> renderer) { super("click", "keyup", "keydown", "blur"); if (template == null) { template = GWT.create(Template.class); } if (format == null) { throw new IllegalArgumentException("format == null"); } if (renderer == null) { throw new IllegalArgumentException("renderer == null"); } this.format = format; this.renderer = renderer; } @Override public void onBrowserEvent(Context context, Element parent, Number value, NativeEvent event, ValueUpdater<Number> valueUpdater) { Object key = context.getKey(); ViewData viewData = getViewData(key); if (viewData != null && viewData.isEditing()) { // Handle the edit event. editEvent(context, parent, value, viewData, event, valueUpdater); } else { String type = event.getType(); int keyCode = event.getKeyCode(); boolean enterPressed = "keyup".equals(type) && keyCode == KeyCodes.KEY_ENTER; if ("click".equals(type) || enterPressed) { // Go into edit mode. if (viewData == null) { viewData = new ViewData(value); setViewData(key, viewData); } else { viewData.setEditing(true); } edit(context, parent, value); } } } @Override public void render(Context context, Number value, SafeHtmlBuilder sb) { // Get the view data. Object key = context.getKey(); ViewData viewData = getViewData(key); if (viewData != null && !viewData.isEditing() && value != null && value.equals(viewData.getNumber())) { clearViewData(key); viewData = null; } if (viewData != null) { Number number = viewData.getNumber(); if (viewData.isEditing()) { /* * Do not use the renderer in edit mode because the value of a text * input element is always treated as text. SafeHtml isn't valid in the * context of the value attribute. */ sb.append(template.input(format.format(number))); } else { // The user pressed enter, but view data still exists. sb.append(renderer.render(format.format(number))); } } else if (value != null) { sb.append(renderer.render(format.format(value))); } //To change body of generated methods, choose Tools | Templates. } @Override public boolean resetFocus(Context context, Element parent, Number value) { if (isEditing(context, parent, value)) { getInputElement(parent).focus(); return true; } return false; } /** * Convert the cell to edit mode. * * @param context the {@link Context} of the cell * @param parent the parent element * @param value the current value */ protected void edit(Context context, Element parent, Number value) { setValue(context, parent, value); InputElement input = getInputElement(parent); input.focus(); input.select(); } /** * Convert the cell to non-edit mode. * * @param context the context of the cell * @param parent the parent Element * @param value the value associated with the cell */ private void cancel(Context context, Element parent, Number value) { clearInput(getInputElement(parent)); setValue(context, parent, value); } /** * Clear selected from the input element. Both Firefox and IE fire spurious * onblur events after the input is removed from the DOM if selection is not * cleared. * * @param input the input element */ private native void clearInput(Element input) /*-{ if (input.selectionEnd) input.selectionEnd = input.selectionStart; else if ($doc.selection) $doc.selection.clear(); }-*/; /** * Commit the current value. * * @param context the context of the cell * @param parent the parent Element * @param viewData the {@link ViewData} object * @param valueUpdater the {@link ValueUpdater} */ private void commit(Context context, Element parent, ViewData viewData, ValueUpdater<Number> valueUpdater) { Number value = updateViewData(parent, viewData, false); clearInput(getInputElement(parent)); setValue(context, parent, viewData.getOriginal()); if (valueUpdater != null) { valueUpdater.update(value); } } private void editEvent(Context context, Element parent, Number value, ViewData viewData, NativeEvent event, ValueUpdater<Number> valueUpdater) { String type = event.getType(); boolean keyUp = "keyup".equals(type); boolean keyDown = "keydown".equals(type); if (keyUp || keyDown) { int keyCode = event.getKeyCode(); if (keyUp && keyCode == KeyCodes.KEY_ENTER) { // Commit the change. commit(context, parent, viewData, valueUpdater); } else if (keyUp && keyCode == KeyCodes.KEY_ESCAPE) { // Cancel edit mode. Number originalText = viewData.getOriginal(); if (viewData.isEditingAgain()) { viewData.setNumber(originalText); viewData.setEditing(false); } else { setViewData(context.getKey(), null); } cancel(context, parent, value); } else { // Update the text in the view data on each key. updateViewData(parent, viewData, true); } } else if ("blur".equals(type)) { // Commit the change. Ensure that we are blurring the input element and // not the parent element itself. EventTarget eventTarget = event.getEventTarget(); if (Element.is(eventTarget)) { Element target = Element.as(eventTarget); if ("input".equals(target.getTagName().toLowerCase())) { commit(context, parent, viewData, valueUpdater); } } } } /** * Get the input element in edit mode. */ private InputElement getInputElement(Element parent) { return parent.getFirstChild().<InputElement>cast(); } /** * Update the view data based on the current value. * * @param parent the parent element * @param viewData the {@link ViewData} object to update * @param isEditing true if in edit mode * @return the new value */ private Number updateViewData(Element parent, ViewData viewData, boolean isEditing) { InputElement input = (InputElement) parent.getFirstChild(); Number value = parseInt(input.getValue()); viewData.setNumber(value); viewData.setEditing(isEditing); return value; } }