Java tutorial
/* * Copyright 2015 John Ahlroos * * 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.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.gridlayout; import com.google.gwt.dom.client.Style; import com.google.gwt.dom.client.Style.Position; import com.google.gwt.dom.client.Style.Unit; import com.google.gwt.user.client.ui.HTML; import com.google.gwt.user.client.ui.UIObject; import com.google.gwt.user.client.ui.Widget; import com.vaadin.client.ApplicationConnection; import com.vaadin.client.ComponentConnector; import com.vaadin.client.MouseEventDetailsBuilder; import com.vaadin.client.Util; import com.vaadin.client.ui.VGridLayout; import com.vaadin.client.ui.dd.VDragEvent; import com.vaadin.shared.MouseEventDetails; import com.vaadin.shared.ui.dd.HorizontalDropLocation; import com.vaadin.shared.ui.dd.VerticalDropLocation; import com.haulmont.cuba.web.widgets.addons.dragdroplayouts.DDGridLayout; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.VDragFilter; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.VGrabFilter; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.*; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.VLayoutDragDropMouseHandler.DragStartListener; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.interfaces.*; import com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.util.IframeCoverUtility; import java.util.Map; /** * Client side implementation for {@link DDGridLayout} * * @author John Ahlroos / www.jasoft.fi * @since 0.4.0 */ public class VDDGridLayout extends VGridLayout implements VHasDragMode, VDDHasDropHandler<VDDGridLayoutDropHandler>, DragStartListener, VHasDragFilter, VHasIframeShims, VHasDragImageReferenceSupport, VHasGrabFilter, VHasDragCaptionProvider { public static final String CLASSNAME = "v-ddgridlayout"; public static final String OVER = CLASSNAME + "-over"; private VDDGridLayoutDropHandler dropHandler; final HTML dragShadow = new HTML(""); protected ApplicationConnection client; private VDragFilter dragFilter; private VDragCaptionProvider dragCaption; private VGrabFilter grabFilter; private final IframeCoverUtility iframeCoverUtility = new IframeCoverUtility(); private float cellLeftRightDropRatio; private float cellTopBottomDropRatio; // The drag mouse handler which handles the creation of the transferable private final VLayoutDragDropMouseHandler ddMouseHandler = new VLayoutDragDropMouseHandler(this, LayoutDragMode.NONE); private LayoutDragMode mode = LayoutDragMode.NONE; private boolean iframeCovers = false; public VDDGridLayout() { super(); } @Override public void setDragCaptionProvider(VDragCaptionProvider dragCaption) { this.dragCaption = dragCaption; } @Override public VDragCaptionProvider getDragCaptionProvider() { return dragCaption; } @Override protected void onLoad() { super.onLoad(); ddMouseHandler.addDragStartListener(this); setDragMode(mode); iframeShimsEnabled(iframeCovers); } @Override protected void onUnload() { super.onUnload(); ddMouseHandler.removeDragStartListener(this); ddMouseHandler.updateDragMode(LayoutDragMode.NONE); iframeCoverUtility.setIframeCoversEnabled(false, getElement(), LayoutDragMode.NONE); } /** * Returns the drop handler used when the user drops a component over the * Grid Layout */ public VDDGridLayoutDropHandler getDropHandler() { return dropHandler; } public void setDropHandler(VDDGridLayoutDropHandler handler) { dropHandler = handler; } /** * Updates the drop details while dragging * * @param event * The drag event */ public void updateDragDetails(VDragEvent event) { CellDetails cd = getCellDetails(event); if (cd != null) { Map<String, Object> ddetails = event.getDropDetails(); // Add row ddetails.put(Constants.DROP_DETAIL_ROW, Integer.valueOf(cd.row)); // Add column ddetails.put(Constants.DROP_DETAIL_COLUMN, Integer.valueOf(cd.column)); // Add horizontal position HorizontalDropLocation hl = getHorizontalDropLocation(cd, event); ddetails.put(Constants.DROP_DETAIL_HORIZONTAL_DROP_LOCATION, hl); // Add vertical position VerticalDropLocation vl = getVerticalDropLocation(cd, event); ddetails.put(Constants.DROP_DETAIL_VERTICAL_DROP_LOCATION, vl); // Check if the cell we are hovering over has content Cell cell = getCell(cd.row, cd.column); ddetails.put(Constants.DROP_DETAIL_EMPTY_CELL, cell != null); // Get class information from child if (cell != null && cell.slot != null) { ComponentConnector child = cell.slot.getChild(); if (child != null) { String className = child.getWidget().getClass().getName(); ddetails.put(Constants.DROP_DETAIL_OVER_CLASS, className); } else { ddetails.put(Constants.DROP_DETAIL_OVER_CLASS, VDDGridLayout.this.getClass().getName()); } } else { ddetails.put(Constants.DROP_DETAIL_OVER_CLASS, VDDGridLayout.this.getClass().getName()); } // Add mouse event details MouseEventDetails details = MouseEventDetailsBuilder.buildMouseEventDetails(event.getCurrentGwtEvent(), getElement()); event.getDropDetails().put(Constants.DROP_DETAIL_MOUSE_EVENT, details.serialize()); } } /** * Returns the horizontal drop location * * @param cell * The cell details * @param event * The drag event * @return */ protected HorizontalDropLocation getHorizontalDropLocation(CellDetails cell, VDragEvent event) { // Get the horizontal location HorizontalDropLocation hdetail; int x = Util.getTouchOrMouseClientX(event.getCurrentGwtEvent()) - getAbsoluteLeft() - cell.x; assert (x >= 0 && x <= cell.width); if (x < cell.width * cellLeftRightDropRatio) { hdetail = HorizontalDropLocation.LEFT; } else if (x < cell.width * (1.0 - cellLeftRightDropRatio)) { hdetail = HorizontalDropLocation.CENTER; } else { hdetail = HorizontalDropLocation.RIGHT; } return hdetail; } /** * Returns the vertical drop location * * @param cell * The cell details * @param event * The drag event * @return */ protected VerticalDropLocation getVerticalDropLocation(CellDetails cell, VDragEvent event) { // Get the vertical location VerticalDropLocation vdetail; int y = Util.getTouchOrMouseClientY(event.getCurrentGwtEvent()) - getAbsoluteTop() - cell.y; assert (y >= 0 && y <= cell.height); if (y < cell.height * cellTopBottomDropRatio) { vdetail = VerticalDropLocation.TOP; } else if (y < cell.height * (1.0 - cellTopBottomDropRatio)) { vdetail = VerticalDropLocation.MIDDLE; } else { vdetail = VerticalDropLocation.BOTTOM; } return vdetail; } /** * Emphasizes a component container when user is hovering a dragged * component over the container. * * @param cell * The container * @param event */ protected void emphasis(CellDetails cell, VDragEvent event) { Style shadowStyle = dragShadow.getElement().getStyle(); shadowStyle.setPosition(Position.ABSOLUTE); shadowStyle.setWidth(cell.width, Unit.PX); shadowStyle.setHeight(cell.height, Unit.PX); shadowStyle.setLeft(cell.x, Unit.PX); shadowStyle.setTop(cell.y, Unit.PX); // Remove any existing empasis deEmphasis(); // Ensure we are not dragging ourself into ourself ComponentConnector draggedConnector = (ComponentConnector) event.getTransferable() .getData(Constants.TRANSFERABLE_DETAIL_COMPONENT); if (draggedConnector != null && draggedConnector.getWidget() == VDDGridLayout.this) { return; } HorizontalDropLocation hl = getHorizontalDropLocation(cell, event); VerticalDropLocation vl = getVerticalDropLocation(cell, event); // Apply over style setStyleName(dragShadow.getElement(), OVER, true); // Add vertical location dependent style setStyleName(dragShadow.getElement(), OVER + "-" + vl.toString().toLowerCase(), true); // Add horizontal location dependent style setStyleName(dragShadow.getElement(), OVER + "-" + hl.toString().toLowerCase(), true); } /** * Removes any emphasis previously set by emphasis */ protected void deEmphasis() { setStyleName(dragShadow.getElement(), OVER, false); // Horizontal styles setStyleName(dragShadow.getElement(), OVER + "-" + HorizontalDropLocation.LEFT.toString().toLowerCase(), false); setStyleName(dragShadow.getElement(), OVER + "-" + HorizontalDropLocation.CENTER.toString().toLowerCase(), false); setStyleName(dragShadow.getElement(), OVER + "-" + HorizontalDropLocation.RIGHT.toString().toLowerCase(), false); // Vertical styles setStyleName(dragShadow.getElement(), OVER + "-" + VerticalDropLocation.TOP.toString().toLowerCase(), false); setStyleName(dragShadow.getElement(), OVER + "-" + VerticalDropLocation.MIDDLE.toString().toLowerCase(), false); setStyleName(dragShadow.getElement(), OVER + "-" + VerticalDropLocation.BOTTOM.toString().toLowerCase(), false); } public LayoutDragMode getDragMode() { return ddMouseHandler.getDragMode(); } /** * A hook for extended components to post process the the drop before it is * sent to the server. Useful if you don't want to override the whole drop * handler. */ protected boolean postDropHook(VDragEvent drag) { // Extended classes can add content here... remove(dragShadow); return true; } /** * A hook for extended components to post process the the enter event. * Useful if you don't want to override the whole drophandler. */ protected void postEnterHook(VDragEvent drag) { // Extended classes can add content here... insert(dragShadow, getElement(), 0, true); } /** * A hook for extended components to post process the the leave event. * Useful if you don't want to override the whole drophandler. */ protected void postLeaveHook(VDragEvent drag) { // Extended classes can add content here... remove(dragShadow); } /** * A hook for extended components to post process the the over event. Useful * if you don't want to override the whole drophandler. */ protected void postOverHook(VDragEvent drag) { // Extended classes can add content here... } /** * Can be used to listen to drag start events, must return true for the drag * to commence. Return false to interrupt the drag: */ public boolean dragStart(Widget widget, LayoutDragMode mode) { ComponentConnector layout = Util.findConnectorFor(this); return VDragDropUtil.isDraggingEnabled(layout, widget); } /** * A helper class returned by getCellDetailsByCoordinates() which contains * positional and size data of the cell. */ protected class CellDetails { public int row = -1; public int column = -1; public int x = -1; public int y = -1; public int width = -1; public int height = -1; } CellDetails getCellDetails(VDragEvent event) { int x = Util.getTouchOrMouseClientX(event.getCurrentGwtEvent()) - getAbsoluteLeft(); int y = Util.getTouchOrMouseClientY(event.getCurrentGwtEvent()) - getAbsoluteTop(); return getCellDetailsByCoordinates(x, y); } /** * Returns details of the cell under the given position * * @param x * The x-coordinate * @param y * The y-coordinate * @return The details of the cell under the coordinate */ private CellDetails getCellDetailsByCoordinates(int x, int y) { CellDetails cd = new CellDetails(); int[] columnWidths = getColumnWidths(); int[] rowHeights = getRowHeights(); // Get column and x coordinate int temp = 0; for (int col = 0; col < columnWidths.length; col++) { if (x >= temp && x <= temp + columnWidths[col]) { cd.column = col; cd.x = temp; cd.width = columnWidths[col]; break; } temp += columnWidths[col] + getHorizontalSpacing(); } // get row temp = 0; for (int row = 0; row < rowHeights.length; row++) { if (y >= temp && y <= temp + rowHeights[row]) { cd.row = row; cd.y = temp; cd.height = rowHeights[row]; break; } temp += rowHeights[row] + getVerticalSpacing(); } // Sanity check if (cd.row == -1 || cd.column == -1 || cd.width == -1 || cd.height == -1) { return null; } return cd; } /* * (non-Javadoc) * * @see com.haulmont.cuba.web.widgets.client.addons.dragdroplayouts.ui.interfaces.VHasDragFilter# * getDragFilter () */ public VDragFilter getDragFilter() { return dragFilter; } IframeCoverUtility getIframeCoverUtility() { return iframeCoverUtility; } @Override public void setDragFilter(VDragFilter filter) { this.dragFilter = filter; } public float getCellLeftRightDropRatio() { return cellLeftRightDropRatio; } public void setCellLeftRightDropRatio(float cellLeftRightDropRatio) { this.cellLeftRightDropRatio = cellLeftRightDropRatio; } public float getCellTopBottomDropRatio() { return cellTopBottomDropRatio; } public void setCellTopBottomDropRatio(float cellTopBottomDropRatio) { this.cellTopBottomDropRatio = cellTopBottomDropRatio; } @Override public void iframeShimsEnabled(boolean enabled) { iframeCovers = enabled; iframeCoverUtility.setIframeCoversEnabled(enabled, getElement(), mode); } @Override public boolean isIframeShimsEnabled() { return iframeCovers; } @Override public void setDragMode(LayoutDragMode mode) { this.mode = mode; ddMouseHandler.updateDragMode(mode); iframeShimsEnabled(iframeCovers); } @Override public void setDragImageProvider(VDragImageProvider provider) { ddMouseHandler.setDragImageProvider(provider); } protected final VLayoutDragDropMouseHandler getMouseHandler() { return ddMouseHandler; } @Override public VGrabFilter getGrabFilter() { return grabFilter; } @Override public void setGrabFilter(VGrabFilter grabFilter) { this.grabFilter = grabFilter; } }