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发表时间:2011-07-27
由于项目的需要,一直想将GXT应用起来,可惜去年做了部分测试后由于身体原因停了下来。休息了大半年,虽然听力依然没 有恢复,但生活还要继续,工作还要努力 。 这段时间相对清闲,为了做一些必要的技术储备,又重新跑一跑GXT。过去半年,重新阅读之前的代码又有了很大的收获。先进入正题: ===================废话的分割线================= 下拉树(Combo Tree)是Ajax框架里非常有用的一个功能,至少在国内是。奇怪的是ExtJS到目前都没有提供一个官方的控件。大部分都使用render的方式将Tree放到Combo中,但是这个方法在GXT中就变得无效。http://www.iteye.com/problems/38852。去年我也是碰到这个问题后找到了这个提问,一直也没人解答。貌似作者还在EXT的官方论坛提问,也没有理。这次重新学习GXT,首先就是要解决这个问题。 首先按照http://www.iteye.com/problems/38852的方法实现了下拉树,确实出现该文中提到的情况,审核元素发现,在树的上级是combo的下拉div,所有的事件在这层已经全部被拦截。要解决只能从这里入手。阅读了ComboBox.java,发现他和ExtJS类似,是使用一个List控件作为其下拉显示,尝试将其替换成TreePanel,初步实现了下拉树的功能。实现声明:该控件不完善,我只是进行了初步的精简和功能替换,还有很多工作需要完成,这里只做一个演示。存在的BUG:第一次展开下拉树不会出现,第二次点击才会出现。原因是TreePanel的加载是在展开之后,第一次没有加载到所有显示不出来。
package com.strong.client.extend; import java.util.ArrayList; import java.util.List; import com.extjs.gxt.ui.client.GXT; import com.extjs.gxt.ui.client.Style.Scroll; import com.extjs.gxt.ui.client.core.El; import com.extjs.gxt.ui.client.core.XDOM; import com.extjs.gxt.ui.client.data.ModelData; import com.extjs.gxt.ui.client.event.ComponentEvent; import com.extjs.gxt.ui.client.event.DomEvent; import com.extjs.gxt.ui.client.event.Events; import com.extjs.gxt.ui.client.event.FieldEvent; import com.extjs.gxt.ui.client.event.ListViewEvent; import com.extjs.gxt.ui.client.event.Listener; import com.extjs.gxt.ui.client.event.PreviewEvent; import com.extjs.gxt.ui.client.event.SelectionChangedEvent; import com.extjs.gxt.ui.client.event.SelectionChangedListener; import com.extjs.gxt.ui.client.event.SelectionProvider; import com.extjs.gxt.ui.client.store.StoreEvent; import com.extjs.gxt.ui.client.store.TreeStore; import com.extjs.gxt.ui.client.util.BaseEventPreview; import com.extjs.gxt.ui.client.util.KeyNav; import com.extjs.gxt.ui.client.util.Util; import com.extjs.gxt.ui.client.widget.LayoutContainer; import com.extjs.gxt.ui.client.widget.form.ListModelPropertyEditor; import com.extjs.gxt.ui.client.widget.form.PropertyEditor; import com.extjs.gxt.ui.client.widget.form.TriggerField; import com.extjs.gxt.ui.client.widget.treepanel.TreePanel; import com.google.gwt.dom.client.Document; import com.google.gwt.dom.client.InputElement; import com.google.gwt.event.dom.client.KeyCodes; import com.google.gwt.user.client.Command; import com.google.gwt.user.client.DeferredCommand; import com.google.gwt.user.client.Element; import com.google.gwt.user.client.Event; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.ui.RootPanel; import com.strong.client.model.FileModel; @SuppressWarnings("deprecation") public class StrongComboBox<D extends ModelData> extends TriggerField<D> implements SelectionProvider<D> { /** * ComboBox error messages. */ public class ComboBoxMessages extends TextFieldMessages { private String loadingText = GXT.MESSAGES.loadMask_msg(); private String valueNoutFoundText; /** * Returns the loading text. * * @return the loading text */ public String getLoadingText() { return loadingText; } /** * Returns the value not found error text. * * @return the error text */ public String getValueNoutFoundText() { return valueNoutFoundText; } /** * Sets the loading text. * * @param loadingText * the loading text */ public void setLoadingText(String loadingText) { this.loadingText = loadingText; } /** * When using a name/value combo, if the value passed to setValue is not * found in the store, valueNotFoundText will be displayed as the field text * if defined. * * @param valueNoutFoundText */ public void setValueNoutFoundText(String valueNoutFoundText) { this.valueNoutFoundText = valueNoutFoundText; } } /** * TriggerAction enum. */ public enum TriggerAction { ALL, QUERY; } protected boolean autoComplete = false; protected boolean delayedCheck; protected TreeStore<D> store; private BaseEventPreview eventPreview; private boolean expanded; private El footer; private boolean forceSelection; private InputElement hiddenInput; private String lastSelectionText; private boolean lazyRender = true, initialized; private LayoutContainer list; private String listAlign = "tl-bl?"; private String listStyle = "x-combo-list"; private TreePanel<D> treePanel; private int maxHeight = 300; private int minChars = 4; private int minListWidth = 70; private D selectedItem; private TriggerAction triggerAction = TriggerAction.QUERY; private boolean typeAhead; private String valueField; /** * Creates a combo box. */ @SuppressWarnings("unchecked") public StrongComboBox(TreeStore<D> treeStore) { this.setStore(treeStore); this.messages = new ComboBoxMessages(); System.out.println("++++++++++++++++++"); this.treePanel = new TreePanel<D>(store); setPropertyEditor(new ListModelPropertyEditor<D>()); this.monitorWindowResize = true; this.windowResizeDelay = 0; initComponent(); } /** * 设置TreePanel用于显示的属性 * * @param strDisplay */ public void setDisplayProperty(String strDisplay) { this.treePanel.setDisplayProperty(FileModel.WEN_JIAN_MING); } public void addSelectionChangedListener(SelectionChangedListener<D> listener) { addListener(Events.SelectionChange, listener); } @Override public void clear() { getStore().clearFilters(); boolean f = forceSelection; forceSelection = false; super.clear(); forceSelection = f; } /** * Clears any text/value currently set in the field. */ public void clearSelections() { setRawValue(""); lastSelectionText = ""; applyEmptyText(); value = null; } /** * Hides the dropdown list if it is currently expanded. Fires the * <i>Collapse</i> event on completion. */ public void collapse() { if (!expanded) { return; } eventPreview.remove(); expanded = false; list.hide(); RootPanel.get().remove(list); if (GXT.isAriaEnabled() && hasFocus) { // inspect 32 is keeping focus on hidden list item in dropdown input.blur(); input.focus(); } fireEvent(Events.Collapse, new FieldEvent(this)); } /** * Execute a query to filter the dropdown list. Fires the BeforeQuery event * prior to performing the query allowing the query action to be canceled if * needed. * * @param q * the query * @param forceAll * true to force the query to execute even if there are currently * fewer characters in the field than the minimum specified by the * minChars config option. It also clears any filter previously saved * in the current store */ public void doQuery(String q, boolean forceAll) { if (q == null) { q = ""; } FieldEvent fe = new FieldEvent(this); fe.setValue(q); if (!fireEvent(Events.BeforeQuery, fe)) { return; } if (forceAll || q.length() >= minChars) { expand(); selectedItem = null; onLoad(null); } } /** * Expands the dropdown list if it is currently hidden. Fires the * <i>expand</i> event on completion. */ public void expand() { if (expanded || !hasFocus) { return; } if (!initialized) { createList(false); } else { RootPanel.get().add(list); } list.show(); list.layout(); list.el().updateZIndex(0); restrict(); eventPreview.add(); expanded = true; fireEvent(Events.Expand, new FieldEvent(this)); } /** * Returns the combo's TreePanel view. * * @return the view */ public TreePanel<D> getTreePanel() { return treePanel; } /** * Returns the loading text. * * @return the loading text */ public String getLoadingText() { return getMessages().getLoadingText(); } /** * Returns the dropdown list's max height. * * @return the max height */ public int getMaxHeight() { return maxHeight; } @SuppressWarnings("unchecked") @Override public ComboBoxMessages getMessages() { return (ComboBoxMessages) messages; } /** * Returns the min characters used for autocompete and typeahead. * * @return the minimum number of characters */ public int getMinChars() { return minChars; } /** * Returns the dropdown list's min width. * * @return the min width */ public int getMinListWidth() { return minListWidth; } @Override public ListModelPropertyEditor<D> getPropertyEditor() { return (ListModelPropertyEditor<D>) propertyEditor; } public List<D> getSelection() { List<D> sel = new ArrayList<D>(); D v = getValue(); if (v != null) { sel.add(v); } return sel; } /** * Returns the combo's store. * * @return the store */ public TreeStore<D> getStore() { return store; } /** * Returns the trigger action. * * @return the trigger action */ public TriggerAction getTriggerAction() { return triggerAction; } @Override public D getValue() { if (!initialized) { return value; } if (store != null) { getPropertyEditor().setList(store.getModels()); } doForce(); return super.getValue(); } /** * Returns the value field name. * * @return the value field name */ public String getValueField() { return valueField; } /** * Returns the combo's list view. * * @return the view */ public TreePanel<D> getView() { return treePanel; } /** * Returns <code>true</code> if the panel is expanded. * * @return the expand state */ public boolean isExpanded() { return expanded; } /** * Returns true if lazy rendering is enabled. * * @return true of lazy rendering */ public boolean isLazyRender() { return lazyRender; } /** * Returns true if type ahead is enabled. * * @return the type ahead state */ public boolean isTypeAhead() { return typeAhead; } public void removeSelectionListener(SelectionChangedListener<D> listener) { removeListener(Events.SelectionChange, listener); } @Override public void reset() { getStore().clearFilters(); boolean f = forceSelection; forceSelection = false; super.reset(); forceSelection = f; } public void select(D sel) { // if (listView != null && sel != null) { // int index = store.indexOf(sel); // selectedItem = sel; // if (index < listView.getElements().size()) { // listView.getSelectionModel().select(sel, false); // fly(listView.getElement(index)).scrollIntoView(listView.getElement(), // false); // } // } System.out.println("===select D===" + sel); } /** * Select an item in the dropdown list by its numeric index in the list. This * function does NOT cause the select event to fire. The list must expanded * for this function to work, otherwise use #setValue. * * @param index * the index of the item to select */ public void select(int index) { // select(store.getAt(index)); System.out.println("===select int===" + index); } /** * The underlying data field name to bind to this ComboBox (defaults to * 'text'). * * @param displayField * the display field */ public void setDisplayField(String displayField) { getPropertyEditor().setDisplayProperty(displayField); } /** * Sets the panel's expand state. * * @param expand * <code>true<code> true to expand */ public void setExpanded(boolean expand) { this.expanded = expand; if (isRendered()) { if (expand) { expand(); } else { collapse(); } } } /** * Sets whether the combo's value is restricted to one of the values in the * list, false to allow the user to set arbitrary text into the field * (defaults to false). * * @param forceSelection * true to force selection */ public void setForceSelection(boolean forceSelection) { this.forceSelection = forceSelection; } /** * True to lazily render the combo's drop down list (default to true, * pre-render). * * @param lazyRender * true to lazy render the drop down list */ public void setLazyRender(boolean lazyRender) { this.lazyRender = lazyRender; } /** * Sets a valid anchor position value. See {@link El#alignTo} for details on * supported anchor positions (defaults to 'tl-bl?'). * * @param listAlign * the new list align value */ public void setListAlign(String listAlign) { this.listAlign = listAlign; } /** * Sets the style for the drop down list (defaults to 'x-combo-list'); * * @param listStyle * the list style */ public void setListStyle(String listStyle) { this.listStyle = listStyle; } /** * Sets the loading text. * * @param loadingText * the loading text */ public void setLoadingText(String loadingText) { getMessages().setLoadingText(loadingText); } /** * Sets the maximum height in pixels of the dropdown list before scrollbars * are shown (defaults to 300). * * @param maxHeight * the max hieght */ public void setMaxHeight(int maxHeight) { this.maxHeight = maxHeight; } /** * Sets the minimum number of characters the user must type before * autocomplete and typeahead active (defaults to 4 if remote, or 0 if local). * * @param minChars */ public void setMinChars(int minChars) { this.minChars = minChars; } /** * Sets the minimum width of the dropdown list in pixels (defaults to 70, will * be ignored if listWidth has a higher value). * * @param minListWidth * the min width */ public void setMinListWidth(int minListWidth) { this.minListWidth = minListWidth; } @Override public void setPropertyEditor(PropertyEditor<D> propertyEditor) { assert propertyEditor instanceof ListModelPropertyEditor<?> : "PropertyEditor must be a ListModelPropertyEditor instance"; super.setPropertyEditor(propertyEditor); } @Override public void setRawValue(String text) { if (rendered) { if (text == null) { String msg = getMessages().getValueNoutFoundText(); text = msg != null ? msg : ""; } getInputEl().setValue(text); } } public void setSelection(List<D> selection) { if (selection.size() > 0) { setValue(selection.get(0)); } else { setValue(null); } } /** * Sets the combo's store. * * @param store * the store */ public void setStore(TreeStore<D> store) { this.store = store; } /** * The action to execute when the trigger field is activated. Use * {@link TriggerAction#ALL} to run the query specified by the allQuery config * option (defaults to {@link TriggerAction#QUERY}). * * @param triggerAction * the trigger action */ public void setTriggerAction(TriggerAction triggerAction) { this.triggerAction = triggerAction; } @Override public void setValue(D value) { D oldValue = this.value; super.setValue(value); updateHiddenValue(); this.lastSelectionText = getRawValue(); if (!Util.equalWithNull(oldValue, value)) { SelectionChangedEvent<D> se = new SelectionChangedEvent<D>(this, getSelection()); fireEvent(Events.SelectionChange, se); } } /** * Sets the model field used to retrieve the "value" from the model. If * specified, a hidden form field will contain the value. The hidden form * field name will be the combo's field name plus "-hidden". * * @param valueField * the value field name */ public void setValueField(String valueField) { this.valueField = valueField; } protected void collapseIf(PreviewEvent pe) { if (!list.el().isOrHasChild(pe.getTarget()) && !el().isOrHasChild(pe.getTarget())) { collapse(); } } protected void doForce() { if (forceSelection) { boolean f = forceSelection; forceSelection = false; String rv = getRawValue(); if (getAllowBlank() && (rv == null || rv.equals(""))) { forceSelection = f; return; } if (getValue() == null) { if (lastSelectionText != null && !"".equals(lastSelectionText)) { setRawValue(lastSelectionText); } else { applyEmptyText(); } } forceSelection = f; } } protected D findModel(String property, String value) { if (value == null) return null; for (D model : store.getModels()) { if (value.equals(getPropertyEditor().getStringValue(model))) { return model; } } return null; } protected void fireKey(FieldEvent fe) { if (fe.isNavKeyPress() && !isExpanded() && !delayedCheck) { fireEvent(Events.SpecialKey, fe); } } protected Element getAlignElement() { return getElement(); } @Override protected El getFocusEl() { return input; } protected boolean hasFocus() { return hasFocus || expanded; } @SuppressWarnings("rawtypes") protected void initComponent() { eventPreview = new BaseEventPreview() { @Override protected boolean onPreview(PreviewEvent pe) { switch (pe.getType().getEventCode()) { case Event.ONSCROLL: case Event.ONMOUSEWHEEL: case Event.ONMOUSEDOWN: collapseIf(pe); break; case Event.ONKEYPRESS: if (expanded && pe.getKeyCode() == KeyCodes.KEY_ENTER) { pe.stopEvent(); onViewClick(pe, false); } break; } return true; } }; eventPreview.setAutoHide(false); new KeyNav(this) { @Override public void onDown(ComponentEvent ce) { if (!isReadOnly()) { ce.cancelBubble(); if (!isExpanded()) { onTriggerClick(ce); } else { selectNext(); } } } @Override public void onEnter(ComponentEvent ce) { if (expanded) { ce.cancelBubble(); onViewClick(ce, false); delayedCheck = true; unsetDelayCheck(); } } @Override public void onEsc(ComponentEvent ce) { if (expanded) { ce.cancelBubble(); collapse(); } } @Override public void onTab(ComponentEvent ce) { if (expanded) { onViewClick(ce, false); } } @Override public void onUp(ComponentEvent ce) { if (expanded) { ce.cancelBubble(); selectPrev(); } } }; } protected void initTree() { if (treePanel == null) { treePanel = new TreePanel<D>(store); } String style = listStyle; treePanel.setStyleAttribute("overflowX", "hidden"); treePanel.addStyleName(style + "-inner"); treePanel.setStyleAttribute("padding", "0px"); treePanel.setBorders(false); treePanel.getSelectionModel().addListener(Events.SelectionChange, new Listener<SelectionChangedEvent<D>>() { public void handleEvent(SelectionChangedEvent<D> se) { selectedItem = treePanel.getSelectionModel().getSelectedItem(); if (GXT.isAriaEnabled()) { // Element e = // listView.getElement(listView.getStore().indexOf(selectedItem)); // StrongComboBox.this.setAriaState("aria-activedescendant", // e.getId()); System.out.println("===SelectionChangedEvent===" + se); } } }); treePanel.addListener(Events.Select, new Listener<ListViewEvent<D>>() { public void handleEvent(ListViewEvent<D> le) { onViewClick(le, true); } }); list = new LayoutContainer() { @Override protected void doAttachChildren() { super.doAttachChildren(); } @Override protected void doDetachChildren() { super.doDetachChildren(); } @Override protected void onRender(Element parent, int index) { super.onRender(parent, index); eventPreview.getIgnoreList().add(getElement()); setAriaRole("presentation"); } }; list.setScrollMode(Scroll.NONE); list.setShim(true); list.setShadow(true); list.setBorders(true); list.setStyleName(style); list.hide(); list.addStyleName("x-ignore"); assert store != null : "ComboBox needs a store"; list.add(treePanel); if (!lazyRender) { createList(true); } } protected void onBeforeLoad(StoreEvent<D> se) { if (!hasFocus()) { return; } if (expanded) { restrict(); } } @Override protected void onDetach() { collapse(); super.onDetach(); if (eventPreview != null) { eventPreview.remove(); } } protected void onEmptyResults() { collapse(); } @Override protected void onKeyDown(FieldEvent fe) { if (fe.getKeyCode() == KeyCodes.KEY_TAB) { if (expanded) { onViewClick(fe, false); } } super.onKeyDown(fe); } protected void onLoad(StoreEvent<D> se) { if (!isAttached() || !hasFocus()) { return; } if (store.getAllItems().size() > 0) { if (expanded) { restrict(); } else { expand(); } } else { onEmptyResults(); } } protected void onRender(Element parent, int index) { super.onRender(parent, index); initTree(); if (!autoComplete) { getInputEl().dom.setAttribute("autocomplete", "off"); } if (valueField != null) { hiddenInput = Document.get().createHiddenInputElement().cast(); hiddenInput.setName(getName() + "-hidden"); getElement().appendChild(hiddenInput); } eventPreview.getIgnoreList().add(getElement()); setAriaState("aria-owns", treePanel.getId()); setAriaRole("combobox"); } protected void onSelect(D model, int index) { FieldEvent fe = new FieldEvent(this); if (fireEvent(Events.BeforeSelect, fe)) { setValue(model); collapse(); fireEvent(Events.Select, fe); } } protected void onTriggerClick(ComponentEvent ce) { super.onTriggerClick(ce); if (expanded) { collapse(); } else { onFocus(null); if (triggerAction != TriggerAction.ALL) { doQuery(getRawValue(), true); } } getInputEl().focus(); } protected void onTypeAhead() { if (store.getAllItems().size() > 0) { D m = store.getChild(0); String newValue = propertyEditor.getStringValue(m); int len = newValue.length(); int selStart = getRawValue().length(); if (selStart != len) { setRawValue(newValue); select(selStart, newValue.length()); } } } protected void onUpdate(StoreEvent<D> se) { // handle the case when the selected model's display property is updated if (!getRawValue().equals("") && getValue() == null && forceSelection) { setValue(null); store.clearFilters(); setValue(se.getModel()); } } protected void onViewClick(DomEvent de, boolean focus) { // int idx = -1; // // when testing in selenium the items will not be selected as the mouse // // is not moved during the test // Element elem = listView.findElement(de.getTarget()); // if (elem != null) { // idx = listView.indexOf(elem); // } else { // D sel = listView.getSelectionModel().getSelectedItem(); // if (sel != null) { // idx = store.indexOf(sel); // } // } // if (idx != -1) { // D sel = store.getAt(idx); // onSelect(sel, idx); // } // // if (focus) { // DeferredCommand.addCommand(new Command() { // public void execute() { // focus(); // } // }); // } System.out.println("===onViewClick===" + de + "==" + focus); } protected void onWindowResize(int width, int height) { collapse(); } protected void restrict() { list.el().setVisibility(false); treePanel.setHeight("auto"); list.setHeight("auto"); int w = Math.max(getWidth(), minListWidth); int fh = footer != null ? footer.getHeight() : 0; int fw = list.el().getFrameWidth("tb") + fh; int h = treePanel.getHeight() + fw; int mH = Math.min(maxHeight, Window.getClientHeight() - 10); h = Math.min(h, mH); list.setSize(w, h); list.el().alignTo(getAlignElement(), listAlign, null); h -= fw; int width = w - list.el().getFrameWidth("lr"); treePanel.syncSize(); treePanel.setSize(width, h); int y = list.el().getY(); int b = y + h + fw; int vh = XDOM.getViewportSize().height + XDOM.getBodyScrollTop(); if (b > vh) { y = y - (b - vh) - 5; list.el().setTop(y); } list.el().setVisibility(true); } @Override protected void triggerBlur(ComponentEvent ce) { doForce(); collapse(); super.triggerBlur(ce); } protected void unsetDelayCheck() { DeferredCommand.addCommand(new Command() { public void execute() { delayedCheck = false; } }); } @Override protected boolean validateBlur(DomEvent e, Element target) { return list == null || (list != null && !list.isVisible() && !list.getElement().isOrHasChild(target)); } @Override protected boolean validateValue(String value) { if (forceSelection) { boolean f = forceSelection; forceSelection = false; if (getValue() == null) { forceSelection = f; String rv = getRawValue(); if (getAllowBlank() && (rv == null || rv.equals(""))) { return true; } markInvalid(getMessages().getBlankText()); return false; } forceSelection = f; } return super.validateValue(value); } private void createList(boolean remove) { RootPanel.get().add(list); initialized = true; if (remove) { RootPanel.get().remove(list); } } private void selectNext() { int count = store.getAllItems().size(); if (count > 0) { int selectedIndex = store.indexOf(selectedItem); if (selectedIndex == -1) { select(0); } else if (selectedIndex < count - 1) { select(selectedIndex + 1); } } } private void selectPrev() { int count = store.getAllItems().size(); if (count > 0) { int selectedIndex = store.indexOf(selectedItem); if (selectedIndex == -1) { select(0); } else if (selectedIndex != 0) { select(selectedIndex - 1); } } } private void updateHiddenValue() { if (hiddenInput != null) { String v = ""; D val = getValue(); if (val != null && val.get(valueField) != null) { v = ((Object) val.get(valueField)).toString(); } hiddenInput.setValue(v); } } } 声明:ITeye文章版权属于作者,受法律保护。没有作者书面许可不得转载。
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发表时间:2011-08-03
好好看看,正好我最近也有这样的需求,不怎么如何解决,暂时绕道用gwt的Cell Browser替代了。我在gxt官方论坛也搜索了,有人提问,但是没有具体的解决方案。支持楼主
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发表时间:2011-08-06
hedajia 写道 好好看看,正好我最近也有这样的需求,不怎么如何解决,暂时绕道用gwt的Cell Browser替代了。我在gxt官方论坛也搜索了,有人提问,但是没有具体的解决方案。支持楼主
其实当初我也郁闷了很久,怎么找不到合适的控件。后来发现和swing/swt一样,所有的控件都能够自行扩展。我只是简单的将之前combo的list控件替换成了treepanel,所有的事情就非常清晰了。我现在已经完成了comboTree的异步加载等。等弄完了放上来大家一起交流一下 |
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