Java tutorial
/* * Copyright 2000-2014 Vaadin Ltd. * * 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.vaadin.client.connectors; import java.util.ArrayList; import java.util.Collection; import com.google.gwt.core.client.JavaScriptObject; import com.google.gwt.core.client.JsArrayString; import com.google.gwt.dom.client.NativeEvent; import com.vaadin.client.BrowserInfo; import com.vaadin.client.JavaScriptConnectorHelper; import com.vaadin.client.Util; import com.vaadin.client.communication.HasJavaScriptConnectorHelper; import com.vaadin.client.renderers.ComplexRenderer; import com.vaadin.client.renderers.Renderer; import com.vaadin.client.widget.grid.CellReference; import com.vaadin.client.widget.grid.RendererCellReference; import com.vaadin.shared.JavaScriptExtensionState; import com.vaadin.shared.ui.Connect; import com.vaadin.ui.renderers.AbstractJavaScriptRenderer; import elemental.json.JsonObject; import elemental.json.JsonValue; /** * Connector for server-side renderer implemented using JavaScript. * * @since 7.4 * @author Vaadin Ltd */ @Connect(AbstractJavaScriptRenderer.class) public class JavaScriptRendererConnector extends AbstractRendererConnector<JsonValue> implements HasJavaScriptConnectorHelper { private final JavaScriptConnectorHelper helper = new JavaScriptConnectorHelper(this); private final JavaScriptObject cellReferenceWrapper = createCellReferenceWrapper(BrowserInfo.get().isIE8()); @Override protected void init() { super.init(); helper.init(); addGetRowKey(helper.getConnectorWrapper()); } private static native JavaScriptObject createCellReferenceWrapper(boolean isIE8) /*-{ var reference = {}; if (isIE8) { // IE8 only supports defineProperty for DOM objects reference = $doc.createElement('div'); } var setProperty = function(name, getter, setter) { var descriptor = { get: getter } if (setter) { descriptor.set = setter; } Object.defineProperty(reference, name, descriptor); }; setProperty("element", function() { return reference.target.@CellReference::getElement()(); }, null); setProperty("rowIndex", function() { return reference.target.@CellReference::getRowIndex()(); }, null); setProperty("columnIndex", function() { return reference.target.@CellReference::getColumnIndex()(); }, null); setProperty("colSpan", function() { return reference.target.@RendererCellReference::getColSpan()(); }, function(colSpan) { reference.target.@RendererCellReference::setColSpan(*)(colSpan); }); return reference; }-*/; @Override public JavaScriptExtensionState getState() { return (JavaScriptExtensionState) super.getState(); } private native void addGetRowKey(JavaScriptObject wrapper) /*-{ var self = this; wrapper.getRowKey = $entry(function(rowIndex) { return @JavaScriptRendererConnector::findRowKey(*)(self, rowIndex); }); }-*/; private static String findRowKey(JavaScriptRendererConnector connector, int rowIndex) { GridConnector gc = (GridConnector) connector.getParent(); JsonObject row = gc.getWidget().getDataSource().getRow(rowIndex); return connector.getRowKey(row); } private boolean hasFunction(String name) { return hasFunction(helper.getConnectorWrapper(), name); } private static native boolean hasFunction(JavaScriptObject wrapper, String name) /*-{ return typeof wrapper[name] === 'function'; }-*/; @Override protected Renderer<JsonValue> createRenderer() { helper.ensureJavascriptInited(); if (!hasFunction("render")) { throw new RuntimeException( "JavaScriptRenderer " + helper.getInitFunctionName() + " must have a function named 'render'"); } final boolean hasInit = hasFunction("init"); final boolean hasDestroy = hasFunction("destroy"); final boolean hasOnActivate = hasFunction("onActivate"); final boolean hasGetConsumedEvents = hasFunction("getConsumedEvents"); final boolean hasOnBrowserEvent = hasFunction("onBrowserEvent"); return new ComplexRenderer<JsonValue>() { @Override public void render(RendererCellReference cell, JsonValue data) { render(helper.getConnectorWrapper(), getJsCell(cell), Util.json2jso(data)); } private JavaScriptObject getJsCell(CellReference<?> cell) { updateCellReference(cellReferenceWrapper, cell); return cellReferenceWrapper; } public native void render(JavaScriptObject wrapper, JavaScriptObject cell, JavaScriptObject data) /*-{ wrapper.render(cell, data); }-*/; @Override public void init(RendererCellReference cell) { if (hasInit) { init(helper.getConnectorWrapper(), getJsCell(cell)); } } private native void init(JavaScriptObject wrapper, JavaScriptObject cell) /*-{ wrapper.init(cell); }-*/; private native void updateCellReference(JavaScriptObject cellWrapper, CellReference<?> target) /*-{ cellWrapper.target = target; }-*/; @Override public void destroy(RendererCellReference cell) { if (hasDestroy) { destory(helper.getConnectorWrapper(), getJsCell(cell)); } else { super.destroy(cell); } } private native void destory(JavaScriptObject wrapper, JavaScriptObject cell) /*-{ wrapper.destory(cell); }-*/; @Override public boolean onActivate(CellReference<?> cell) { if (hasOnActivate) { return onActivate(helper.getConnectorWrapper(), getJsCell(cell)); } else { return super.onActivate(cell); } } private native boolean onActivate(JavaScriptObject wrapper, JavaScriptObject cell) /*-{ return !!wrapper.onActivate(cell); }-*/; @Override public Collection<String> getConsumedEvents() { if (hasGetConsumedEvents) { JsArrayString events = getConsumedEvents(helper.getConnectorWrapper()); ArrayList<String> list = new ArrayList<String>(events.length()); for (int i = 0; i < events.length(); i++) { list.add(events.get(i)); } return list; } else { return super.getConsumedEvents(); } } private native JsArrayString getConsumedEvents(JavaScriptObject wrapper) /*-{ var rawEvents = wrapper.getConsumedEvents(); var events = []; for(var i = 0; i < rawEvents.length; i++) { events[i] = ""+rawEvents[i]; } return events; }-*/; @Override public boolean onBrowserEvent(CellReference<?> cell, NativeEvent event) { if (hasOnBrowserEvent) { return onBrowserEvent(helper.getConnectorWrapper(), getJsCell(cell), event); } else { return super.onBrowserEvent(cell, event); } } private native boolean onBrowserEvent(JavaScriptObject wrapper, JavaScriptObject cell, NativeEvent event) /*-{ return !!wrapper.onBrowserEvent(cell, event); }-*/; }; } @Override public JsonValue decode(JsonValue value) { // Let the js logic decode the raw json that the server sent return value; } @Override public void onUnregister() { super.onUnregister(); helper.onUnregister(); } @Override public JavaScriptConnectorHelper getJavascriptConnectorHelper() { return helper; } }