Java tutorial
/* * Copyright 2010 Google Inc. * * 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 org.jbpm.console.ng.gc.client.experimental.pagination; import com.github.gwtbootstrap.client.ui.Button; import com.github.gwtbootstrap.client.ui.SimplePager; import com.github.gwtbootstrap.client.ui.SimplePager.ImageButtonsConstants; import com.github.gwtbootstrap.client.ui.Tooltip; import com.github.gwtbootstrap.client.ui.constants.ButtonType; import com.github.gwtbootstrap.client.ui.constants.IconType; import com.github.gwtbootstrap.client.ui.constants.Placement; import com.google.gwt.core.client.GWT; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.i18n.client.NumberFormat; import com.google.gwt.uibinder.client.UiConstructor; import com.google.gwt.user.cellview.client.AbstractPager; import com.google.gwt.user.cellview.client.SimplePager.Resources; import com.google.gwt.user.cellview.client.SimplePager.Style; import com.google.gwt.user.client.ui.HTML; import com.google.gwt.user.client.ui.HasVerticalAlignment; import com.google.gwt.user.client.ui.HorizontalPanel; import com.google.gwt.view.client.HasRows; import com.google.gwt.view.client.Range; import org.jbpm.console.ng.gc.client.util.DataGridUtils; /** * A pager for controlling a {@link HasRows} that only supports simple page * navigation. * * <p> * <h3>Example</h3> * * <pre> * <b:CellTable pageSize="10" ui:field="table" width="100%" /> * <div> * <b:SimplePager display="{table}" location="RIGHT" fastForwardRows="50"/> * </div> * </pre> * * </p> */ public class JBPMSimplePager<T> extends AbstractPager { /** * The location of the text relative to the paging buttons. */ public static enum TextLocation { CENTER, LEFT, RIGHT; } private static final int DEFAULT_FAST_FORWARD_ROWS = 100; private static Resources DEFAULT_RESOURCES; private static Resources getDefaultResources() { if (DEFAULT_RESOURCES == null) { DEFAULT_RESOURCES = GWT.create(Resources.class); } return DEFAULT_RESOURCES; } private final int tooltipDelay = 1000; private final Placement tooltipPlacement = Placement.BOTTOM; private final Button fastForward; private final Tooltip fastForwardTooltip; private int fastForwardRows; private int currentPage = 0; private int clientSidePages = 3; private int pageSize = 10; private final Button firstPage; private final Tooltip firstPageTooltip; /** * We use an {@link HTML} so we can embed the loading image. */ private final HTML label = new HTML(); private final Button lastPage; private final Button nextPage; private final Button prevPage; private final Tooltip lastPageTooltip; private final Tooltip nextPageTooltip; private final Tooltip prevPageTooltip; /** * The {@link Resources} used by this widget. */ private final Resources resources; /** * The {@link Style} used by this widget. */ private final Style style; private GenericDataProvider<T> dataProvider; public JBPMSimplePager(GenericDataProvider<T> dataProvider) { this(); this.dataProvider = dataProvider; } /** * Construct a {@link SimplePager} with the default text location. */ public JBPMSimplePager() { this(TextLocation.CENTER); } /** * Construct a {@link SimplePager} with the specified text location. * * @param location the location of the text relative to the buttons */ @UiConstructor // Hack for Google I/O demo public JBPMSimplePager(TextLocation location) { this(location, getDefaultResources(), false, DEFAULT_FAST_FORWARD_ROWS, false); } /** * Construct a {@link SimplePager} with the default resources, fast forward * rows and default image button names. * * @param location the location of the text relative to the buttons * @param showFastForwardButton if true, show a fast-forward button that * advances by a larger increment than a single page * @param showLastPageButton if true, show a button to go the the last page */ public JBPMSimplePager(TextLocation location, boolean showFastForwardButton, boolean showLastPageButton) { this(location, showFastForwardButton, DEFAULT_FAST_FORWARD_ROWS, showLastPageButton); } /** * Construct a {@link SimplePager} with the default resources and default * image button names. * * @param location the location of the text relative to the buttons * @param showFastForwardButton if true, show a fast-forward button that * advances by a larger increment than a single page * @param fastForwardRows the number of rows to jump when fast forwarding * @param showLastPageButton if true, show a button to go the the last page */ public JBPMSimplePager(TextLocation location, boolean showFastForwardButton, final int fastForwardRows, boolean showLastPageButton) { this(location, getDefaultResources(), showFastForwardButton, fastForwardRows, showLastPageButton); } /** * Construct a {@link SimplePager} with the specified resources. * * @param location the location of the text relative to the buttons * @param resources the {@link Resources} to use * @param showFastForwardButton if true, show a fast-forward button that * advances by a larger increment than a single page * @param fastForwardRows the number of rows to jump when fast forwarding * @param showLastPageButton if true, show a button to go the the last page * @param imageButtonConstants Constants that contain the image button names */ public JBPMSimplePager(TextLocation location, Resources resources, boolean showFastForwardButton, final int fastForwardRows, boolean showLastPageButton, ImageButtonsConstants imageButtonConstants) { this.resources = resources; this.fastForwardRows = fastForwardRows; this.style = this.resources.simplePagerStyle(); this.style.ensureInjected(); // Create the buttons. firstPage = new Button(); firstPage.setType(ButtonType.LINK); firstPage.setIcon(IconType.FAST_BACKWARD); firstPage.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { firstPage(); } }); firstPageTooltip = new Tooltip(imageButtonConstants.firstPage()); firstPageTooltip.setWidget(firstPage); firstPageTooltip.setPlacement(tooltipPlacement); firstPageTooltip.setShowDelay(tooltipDelay); nextPage = new Button(); nextPage.setType(ButtonType.LINK); nextPage.setIcon(IconType.STEP_FORWARD); nextPage.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { nextPage(); } }); nextPageTooltip = new Tooltip(imageButtonConstants.nextPage()); nextPageTooltip.setWidget(nextPage); nextPageTooltip.setPlacement(tooltipPlacement); nextPageTooltip.setShowDelay(tooltipDelay); prevPage = new Button(); prevPage.setType(ButtonType.LINK); prevPage.setIcon(IconType.STEP_BACKWARD); prevPage.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { previousPage(); } }); prevPageTooltip = new Tooltip(imageButtonConstants.prevPage()); prevPageTooltip.setWidget(prevPage); prevPageTooltip.setPlacement(tooltipPlacement); prevPageTooltip.setShowDelay(tooltipDelay); if (showLastPageButton) { lastPage = new Button(); lastPage.setType(ButtonType.LINK); lastPage.setIcon(IconType.FAST_FORWARD); lastPage.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { lastPage(); } }); lastPageTooltip = new Tooltip(imageButtonConstants.lastPage()); lastPageTooltip.setWidget(lastPage); lastPageTooltip.setPlacement(tooltipPlacement); lastPageTooltip.setShowDelay(tooltipDelay); } else { lastPage = null; lastPageTooltip = null; } if (showFastForwardButton) { fastForward = new Button(); fastForward.setType(ButtonType.LINK); fastForward.setIcon(IconType.FORWARD); fastForward.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { setPage(getPage() + getFastForwardPages()); } }); fastForwardTooltip = new Tooltip(imageButtonConstants.fastForward()); fastForwardTooltip.setWidget(fastForward); fastForwardTooltip.setPlacement(tooltipPlacement); fastForwardTooltip.setShowDelay(tooltipDelay); } else { fastForward = null; fastForwardTooltip = null; } // Construct the widget. HorizontalPanel layout = new HorizontalPanel(); layout.setVerticalAlignment(HasVerticalAlignment.ALIGN_MIDDLE); initWidget(layout); if (location == TextLocation.LEFT) { layout.add(label); } layout.add(firstPage); layout.add(prevPage); if (location == TextLocation.CENTER) { layout.add(label); } layout.add(nextPage); if (showFastForwardButton) { layout.add(fastForward); } if (showLastPageButton) { layout.add(lastPage); } layout.add(firstPageTooltip); layout.add(prevPageTooltip); layout.add(nextPageTooltip); if (showFastForwardButton) { layout.add(fastForwardTooltip); } if (showLastPageButton) { layout.add(lastPageTooltip); } if (location == TextLocation.RIGHT) { layout.add(label); } // Add style names to the cells. firstPage.getElement().getParentElement().addClassName(style.button()); prevPage.getElement().getParentElement().addClassName(style.button()); label.getElement().getParentElement().addClassName(style.pageDetails()); nextPage.getElement().getParentElement().addClassName(style.button()); if (showFastForwardButton) { fastForward.getElement().getParentElement().addClassName(style.button()); } if (showLastPageButton) { lastPage.getElement().getParentElement().addClassName(style.button()); } // Disable the buttons by default. setDisplay(null); } /** * Construct a {@link SimplePager} with the specified resources and default * image button names. * * @param location the location of the text relative to the buttons * @param resources the {@link Resources} to use * @param showFastForwardButton if true, show a fast-forward button that * advances by a larger increment than a single page * @param fastForwardRows the number of rows to jump when fast forwarding * @param showLastPageButton if true, show a button to go the the last page */ public JBPMSimplePager(TextLocation location, Resources resources, boolean showFastForwardButton, final int fastForwardRows, boolean showLastPageButton) { this(location, resources, showFastForwardButton, fastForwardRows, showLastPageButton, GWT.<ImageButtonsConstants>create(ImageButtonsConstants.class)); } @Override public void firstPage() { currentPage = 0; super.firstPage(); previousPage(); } @Override public int getPage() { return currentPage; } @Override public int getPageCount() { return super.getPageCount(); } @Override public boolean hasNextPage() { if (dataProvider != null && dataProvider.getAllServerSideData() != null) { return (dataProvider.getClientSideDataProvider().getList() .size() > (DataGridUtils.pageSize * (currentPage + 1))); } return false; } @Override public boolean hasNextPages(int pages) { return super.hasNextPages(pages); } @Override public boolean hasPage(int index) { return super.hasPage(index); } @Override public boolean hasPreviousPage() { return super.hasPreviousPage(); } @Override public boolean hasPreviousPages(int pages) { return super.hasPreviousPages(pages); } @Override public void lastPage() { super.lastPage(); } @Override public void lastPageStart() { super.lastPageStart(); } @Override public void nextPage() { currentPage++; HasRows display = getDisplay(); Range range = display.getVisibleRange(); int pageStart = range.getStart(); int pageSizeLocal = range.getLength(); int dataSize = display.getRowCount(); int endIndex = Math.min(dataSize, pageStart + pageSizeLocal - 1); // if (presenter != null && (endIndex > (dataSize - this.pageSize - 2))) { // presenter.refreshTasks(presenter.getCurrentDate(), presenter.getCurrentView(), // presenter.getCurrentTaskType(), ((currentPage + 1) * this.pageSize), // this.pageSize , false); // } if (dataProvider != null && (endIndex > (dataSize - this.pageSize - 2))) { dataProvider.refresh(((currentPage + 1) * this.pageSize), this.pageSize, false); } super.nextPage(); } @Override public void previousPage() { if (currentPage > 0) { currentPage--; } //@TODO: I need to create a method to remove data from the server side and client side // if (presenter != null) { // presenter.refreshTasks(presenter.getCurrentDate(), presenter.getCurrentView(), presenter.getCurrentTaskType(), (currentPage * DataGridUtils.pageSize), DataGridUtils.pageSize * 3); // } super.previousPage(); } @Override public void setDisplay(HasRows display) { // Enable or disable all buttons. boolean disableButtons = (display == null); setFastForwardDisabled(disableButtons); setNextPageButtonsDisabled(disableButtons); setPrevPageButtonsDisabled(disableButtons); super.setDisplay(display); } @Override public void setPage(int index) { super.setPage(index); } @Override public void setPageSize(int pageSize) { super.setPageSize(pageSize); } @Override public void setPageStart(int index) { super.setPageStart(index); } /** * Let the page know that the table is loading. Call this method to clear * all data from the table and hide the current range when new data is being * loaded into the table. */ public void startLoading() { getDisplay().setRowCount(0, true); label.setHTML(""); } /** * Get the text to display in the pager that reflects the state of the * pager. * * @return the text */ protected String createText() { // Default text is 1 based. NumberFormat formatter = NumberFormat.getFormat("#,###"); HasRows display = getDisplay(); Range range = display.getVisibleRange(); int pageStart = range.getStart() + 1; int pageSize = range.getLength(); int dataSize = display.getRowCount(); int endIndex = Math.min(dataSize, pageStart + pageSize - 1); endIndex = Math.max(pageStart, endIndex); boolean exact = display.isRowCountExact(); return formatter.format(pageStart) + "-" + formatter.format(endIndex) + (exact ? " of " : " of over ") + formatter.format(dataSize); } @Override protected void onRangeOrRowCountChanged() { HasRows display = getDisplay(); label.setText(createText()); // Update the prev and first buttons. setPrevPageButtonsDisabled(!hasPreviousPage()); setNextPageButtonsDisabled(!hasNextPage()); } /** * Check if the next button is disabled. Visible for testing. */ boolean isNextButtonDisabled() { return !nextPage.isEnabled(); } /** * Check if the previous button is disabled. Visible for testing. */ boolean isPreviousButtonDisabled() { return !prevPage.isEnabled(); } /** * Get the number of pages to fast forward based on the current page size. * * @return the number of pages to fast forward */ private int getFastForwardPages() { int pageSize = getPageSize(); return pageSize > 0 ? fastForwardRows / pageSize : 0; } public int getFastForwardRows() { return fastForwardRows; } public void setFastForwardRows(int fastForwardRows) { this.fastForwardRows = fastForwardRows; } /** * Enable or disable the fast forward button. * * @param disabled true to disable, false to enable */ private void setFastForwardDisabled(boolean disabled) { if (fastForward != null) { fastForward.setEnabled(!disabled); if (disabled) { fastForward.getElement().addClassName(style.disabledButton()); } else { fastForward.getElement().removeClassName(style.disabledButton()); } } } /** * Enable or disable the next page buttons. * * @param disabled true to disable, false to enable */ private void setNextPageButtonsDisabled(boolean disabled) { nextPage.setEnabled(!disabled); if (disabled) { nextPage.getElement().addClassName(style.disabledButton()); } else { nextPage.getElement().removeClassName(style.disabledButton()); } if (lastPage != null) { lastPage.setEnabled(!disabled); if (disabled) { lastPage.getElement().addClassName(style.disabledButton()); } else { lastPage.getElement().removeClassName(style.disabledButton()); } } } /** * Enable or disable the previous page buttons. * * @param disabled true to disable, false to enable */ private void setPrevPageButtonsDisabled(boolean disabled) { firstPage.setEnabled(!disabled); prevPage.setEnabled(!disabled); if (disabled) { firstPage.getElement().addClassName(style.disabledButton()); prevPage.getElement().addClassName(style.disabledButton()); } else { firstPage.getElement().removeClassName(style.disabledButton()); prevPage.getElement().removeClassName(style.disabledButton()); } } public int getCurrentPage() { return currentPage; } public void setDataProvider(GenericDataProvider<T> dataProvider) { this.dataProvider = dataProvider; } }