| 1 | package com.googlecode.lanterna.gui2.table; |
| 2 | |
| 3 | import com.googlecode.lanterna.gui2.*; |
| 4 | import com.googlecode.lanterna.input.KeyStroke; |
| 5 | |
| 6 | /** |
| 7 | * The table class is an interactable component that displays a grid of cells containing data along with a header of |
| 8 | * labels. It supports scrolling when the number of rows and/or columns gets too large to fit and also supports |
| 9 | * user selection which is either row-based or cell-based. User will move the current selection by using the arrow keys |
| 10 | * on the keyboard. |
| 11 | * @param <V> Type of data to store in the table cells, presented through {@code toString()} |
| 12 | * @author Martin |
| 13 | */ |
| 14 | public class Table<V> extends AbstractInteractableComponent<Table<V>> { |
| 15 | private TableModel<V> tableModel; |
| 16 | private TableHeaderRenderer<V> tableHeaderRenderer; |
| 17 | private TableCellRenderer<V> tableCellRenderer; |
| 18 | private Runnable selectAction; |
| 19 | private boolean cellSelection; |
| 20 | private int visibleRows; |
| 21 | private int visibleColumns; |
| 22 | private int viewTopRow; |
| 23 | private int viewLeftColumn; |
| 24 | private int selectedRow; |
| 25 | private int selectedColumn; |
| 26 | private boolean escapeByArrowKey; |
| 27 | |
| 28 | /** |
| 29 | * Creates a new {@code Table} with the number of columns as specified by the array of labels |
| 30 | * @param columnLabels Creates one column per label in the array, must be more than one |
| 31 | */ |
| 32 | public Table(String... columnLabels) { |
| 33 | if(columnLabels.length == 0) { |
| 34 | throw new IllegalArgumentException("Table needs at least one column"); |
| 35 | } |
| 36 | this.tableHeaderRenderer = new DefaultTableHeaderRenderer<V>(); |
| 37 | this.tableCellRenderer = new DefaultTableCellRenderer<V>(); |
| 38 | this.tableModel = new TableModel<V>(columnLabels); |
| 39 | this.selectAction = null; |
| 40 | this.visibleColumns = 0; |
| 41 | this.visibleRows = 0; |
| 42 | this.viewTopRow = 0; |
| 43 | this.viewLeftColumn = 0; |
| 44 | this.cellSelection = false; |
| 45 | this.selectedRow = 0; |
| 46 | this.selectedColumn = -1; |
| 47 | this.escapeByArrowKey = true; |
| 48 | } |
| 49 | |
| 50 | /** |
| 51 | * Returns the underlying table model |
| 52 | * @return Underlying table model |
| 53 | */ |
| 54 | public TableModel<V> getTableModel() { |
| 55 | return tableModel; |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * Updates the table with a new table model, effectively replacing the content of the table completely |
| 60 | * @param tableModel New table model |
| 61 | * @return Itself |
| 62 | */ |
| 63 | public synchronized Table<V> setTableModel(TableModel<V> tableModel) { |
| 64 | if(tableModel == null) { |
| 65 | throw new IllegalArgumentException("Cannot assign a null TableModel"); |
| 66 | } |
| 67 | this.tableModel = tableModel; |
| 68 | invalidate(); |
| 69 | return this; |
| 70 | } |
| 71 | |
| 72 | /** |
| 73 | * Returns the {@code TableCellRenderer} used by this table when drawing cells |
| 74 | * @return {@code TableCellRenderer} used by this table when drawing cells |
| 75 | */ |
| 76 | public TableCellRenderer<V> getTableCellRenderer() { |
| 77 | return tableCellRenderer; |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * Replaces the {@code TableCellRenderer} used by this table when drawing cells |
| 82 | * @param tableCellRenderer New {@code TableCellRenderer} to use |
| 83 | * @return Itself |
| 84 | */ |
| 85 | public synchronized Table<V> setTableCellRenderer(TableCellRenderer<V> tableCellRenderer) { |
| 86 | this.tableCellRenderer = tableCellRenderer; |
| 87 | invalidate(); |
| 88 | return this; |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Returns the {@code TableHeaderRenderer} used by this table when drawing the table's header |
| 93 | * @return {@code TableHeaderRenderer} used by this table when drawing the table's header |
| 94 | */ |
| 95 | public TableHeaderRenderer<V> getTableHeaderRenderer() { |
| 96 | return tableHeaderRenderer; |
| 97 | } |
| 98 | |
| 99 | /** |
| 100 | * Replaces the {@code TableHeaderRenderer} used by this table when drawing the table's header |
| 101 | * @param tableHeaderRenderer New {@code TableHeaderRenderer} to use |
| 102 | * @return Itself |
| 103 | */ |
| 104 | public synchronized Table<V> setTableHeaderRenderer(TableHeaderRenderer<V> tableHeaderRenderer) { |
| 105 | this.tableHeaderRenderer = tableHeaderRenderer; |
| 106 | invalidate(); |
| 107 | return this; |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * Sets the number of columns this table should show. If there are more columns in the table model, a scrollbar will |
| 112 | * be used to allow the user to scroll left and right and view all columns. |
| 113 | * @param visibleColumns Number of columns to display at once |
| 114 | */ |
| 115 | public synchronized void setVisibleColumns(int visibleColumns) { |
| 116 | this.visibleColumns = visibleColumns; |
| 117 | invalidate(); |
| 118 | } |
| 119 | |
| 120 | /** |
| 121 | * Returns the number of columns this table will show. If there are more columns in the table model, a scrollbar |
| 122 | * will be used to allow the user to scroll left and right and view all columns. |
| 123 | * @return Number of visible columns for this table |
| 124 | */ |
| 125 | public int getVisibleColumns() { |
| 126 | return visibleColumns; |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * Sets the number of rows this table will show. If there are more rows in the table model, a scrollbar will be used |
| 131 | * to allow the user to scroll up and down and view all rows. |
| 132 | * @param visibleRows Number of rows to display at once |
| 133 | */ |
| 134 | public synchronized void setVisibleRows(int visibleRows) { |
| 135 | this.visibleRows = visibleRows; |
| 136 | invalidate(); |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Returns the number of rows this table will show. If there are more rows in the table model, a scrollbar will be |
| 141 | * used to allow the user to scroll up and down and view all rows. |
| 142 | * @return Number of rows to display at once |
| 143 | */ |
| 144 | public int getVisibleRows() { |
| 145 | return visibleRows; |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Returns the index of the row that is currently the first row visible. This is always 0 unless scrolling has been |
| 150 | * enabled and either the user or the software (through {@code setViewTopRow(..)}) has scrolled down. |
| 151 | * @return Index of the row that is currently the first row visible |
| 152 | */ |
| 153 | public int getViewTopRow() { |
| 154 | return viewTopRow; |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Sets the view row offset for the first row to display in the table. Calling this with 0 will make the first row |
| 159 | * in the model be the first visible row in the table. |
| 160 | * |
| 161 | * @param viewTopRow Index of the row that is currently the first row visible |
| 162 | * @return Itself |
| 163 | */ |
| 164 | public synchronized Table<V> setViewTopRow(int viewTopRow) { |
| 165 | this.viewTopRow = viewTopRow; |
| 166 | return this; |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | * Returns the index of the column that is currently the first column visible. This is always 0 unless scrolling has |
| 171 | * been enabled and either the user or the software (through {@code setViewLeftColumn(..)}) has scrolled to the |
| 172 | * right. |
| 173 | * @return Index of the column that is currently the first column visible |
| 174 | */ |
| 175 | public int getViewLeftColumn() { |
| 176 | return viewLeftColumn; |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * Sets the view column offset for the first column to display in the table. Calling this with 0 will make the first |
| 181 | * column in the model be the first visible column in the table. |
| 182 | * |
| 183 | * @param viewLeftColumn Index of the column that is currently the first column visible |
| 184 | * @return Itself |
| 185 | */ |
| 186 | public synchronized Table<V> setViewLeftColumn(int viewLeftColumn) { |
| 187 | this.viewLeftColumn = viewLeftColumn; |
| 188 | return this; |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Returns the currently selection column index, if in cell-selection mode. Otherwise it returns -1. |
| 193 | * @return In cell-selection mode returns the index of the selected column, otherwise -1 |
| 194 | */ |
| 195 | public int getSelectedColumn() { |
| 196 | return selectedColumn; |
| 197 | } |
| 198 | |
| 199 | /** |
| 200 | * If in cell selection mode, updates which column is selected and ensures the selected column is visible in the |
| 201 | * view. If not in cell selection mode, does nothing. |
| 202 | * @param selectedColumn Index of the column that should be selected |
| 203 | * @return Itself |
| 204 | */ |
| 205 | public synchronized Table<V> setSelectedColumn(int selectedColumn) { |
| 206 | if(cellSelection) { |
| 207 | this.selectedColumn = selectedColumn; |
| 208 | ensureSelectedItemIsVisible(); |
| 209 | } |
| 210 | return this; |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Returns the index of the currently selected row |
| 215 | * @return Index of the currently selected row |
| 216 | */ |
| 217 | public int getSelectedRow() { |
| 218 | return selectedRow; |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * Sets the index of the selected row and ensures the selected row is visible in the view |
| 223 | * @param selectedRow Index of the row to select |
| 224 | * @return Itself |
| 225 | */ |
| 226 | public synchronized Table<V> setSelectedRow(int selectedRow) { |
| 227 | this.selectedRow = selectedRow; |
| 228 | ensureSelectedItemIsVisible(); |
| 229 | return this; |
| 230 | } |
| 231 | |
| 232 | /** |
| 233 | * If {@code true}, the user will be able to select and navigate individual cells, otherwise the user can only |
| 234 | * select full rows. |
| 235 | * @param cellSelection {@code true} if cell selection should be enabled, {@code false} for row selection |
| 236 | * @return Itself |
| 237 | */ |
| 238 | public synchronized Table<V> setCellSelection(boolean cellSelection) { |
| 239 | this.cellSelection = cellSelection; |
| 240 | if(cellSelection && selectedColumn == -1) { |
| 241 | selectedColumn = 0; |
| 242 | } |
| 243 | else if(!cellSelection) { |
| 244 | selectedColumn = -1; |
| 245 | } |
| 246 | return this; |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * Returns {@code true} if this table is in cell-selection mode, otherwise {@code false} |
| 251 | * @return {@code true} if this table is in cell-selection mode, otherwise {@code false} |
| 252 | */ |
| 253 | public boolean isCellSelection() { |
| 254 | return cellSelection; |
| 255 | } |
| 256 | |
| 257 | /** |
| 258 | * Assigns an action to run whenever the user presses the enter key while focused on the table. If called with |
| 259 | * {@code null}, no action will be run. |
| 260 | * @param selectAction Action to perform when user presses the enter key |
| 261 | * @return Itself |
| 262 | */ |
| 263 | public synchronized Table<V> setSelectAction(Runnable selectAction) { |
| 264 | this.selectAction = selectAction; |
| 265 | return this; |
| 266 | } |
| 267 | |
| 268 | /** |
| 269 | * Returns {@code true} if this table can be navigated away from when the selected row is at one of the extremes and |
| 270 | * the user presses the array key to continue in that direction. With {@code escapeByArrowKey} set to {@code true}, |
| 271 | * this will move focus away from the table in the direction the user pressed, if {@code false} then nothing will |
| 272 | * happen. |
| 273 | * @return {@code true} if user can switch focus away from the table using arrow keys, {@code false} otherwise |
| 274 | */ |
| 275 | public boolean isEscapeByArrowKey() { |
| 276 | return escapeByArrowKey; |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * Sets the flag for if this table can be navigated away from when the selected row is at one of the extremes and |
| 281 | * the user presses the array key to continue in that direction. With {@code escapeByArrowKey} set to {@code true}, |
| 282 | * this will move focus away from the table in the direction the user pressed, if {@code false} then nothing will |
| 283 | * happen. |
| 284 | * @param escapeByArrowKey {@code true} if user can switch focus away from the table using arrow keys, {@code false} otherwise |
| 285 | * @return Itself |
| 286 | */ |
| 287 | public synchronized Table<V> setEscapeByArrowKey(boolean escapeByArrowKey) { |
| 288 | this.escapeByArrowKey = escapeByArrowKey; |
| 289 | return this; |
| 290 | } |
| 291 | |
| 292 | @Override |
| 293 | protected TableRenderer<V> createDefaultRenderer() { |
| 294 | return new DefaultTableRenderer<V>(); |
| 295 | } |
| 296 | |
| 297 | @Override |
| 298 | public TableRenderer<V> getRenderer() { |
| 299 | return (TableRenderer<V>)super.getRenderer(); |
| 300 | } |
| 301 | |
| 302 | @Override |
| 303 | public Result handleKeyStroke(KeyStroke keyStroke) { |
| 304 | switch(keyStroke.getKeyType()) { |
| 305 | case ArrowUp: |
| 306 | if(selectedRow > 0) { |
| 307 | selectedRow--; |
| 308 | } |
| 309 | else if(escapeByArrowKey) { |
| 310 | return Result.MOVE_FOCUS_UP; |
| 311 | } |
| 312 | break; |
| 313 | case ArrowDown: |
| 314 | if(selectedRow < tableModel.getRowCount() - 1) { |
| 315 | selectedRow++; |
| 316 | } |
| 317 | else if(escapeByArrowKey) { |
| 318 | return Result.MOVE_FOCUS_DOWN; |
| 319 | } |
| 320 | break; |
| 321 | case ArrowLeft: |
| 322 | if(cellSelection && selectedColumn > 0) { |
| 323 | selectedColumn--; |
| 324 | } |
| 325 | else if(escapeByArrowKey) { |
| 326 | return Result.MOVE_FOCUS_LEFT; |
| 327 | } |
| 328 | break; |
| 329 | case ArrowRight: |
| 330 | if(cellSelection && selectedColumn < tableModel.getColumnCount() - 1) { |
| 331 | selectedColumn++; |
| 332 | } |
| 333 | else if(escapeByArrowKey) { |
| 334 | return Result.MOVE_FOCUS_RIGHT; |
| 335 | } |
| 336 | break; |
| 337 | case Enter: |
| 338 | Runnable runnable = selectAction; //To avoid synchronizing |
| 339 | if(runnable != null) { |
| 340 | runnable.run(); |
| 341 | } |
| 342 | else { |
| 343 | return Result.MOVE_FOCUS_NEXT; |
| 344 | } |
| 345 | break; |
| 346 | default: |
| 347 | return super.handleKeyStroke(keyStroke); |
| 348 | } |
| 349 | ensureSelectedItemIsVisible(); |
| 350 | invalidate(); |
| 351 | return Result.HANDLED; |
| 352 | } |
| 353 | |
| 354 | private void ensureSelectedItemIsVisible() { |
| 355 | if(visibleRows > 0 && selectedRow < viewTopRow) { |
| 356 | viewTopRow = selectedRow; |
| 357 | } |
| 358 | else if(visibleRows > 0 && selectedRow >= viewTopRow + visibleRows) { |
| 359 | viewTopRow = Math.max(0, selectedRow - visibleRows + 1); |
| 360 | } |
| 361 | if(selectedColumn != -1) { |
| 362 | if(visibleColumns > 0 && selectedColumn < viewLeftColumn) { |
| 363 | viewLeftColumn = selectedColumn; |
| 364 | } |
| 365 | else if(visibleColumns > 0 && selectedColumn >= viewLeftColumn + visibleColumns) { |
| 366 | viewLeftColumn = Math.max(0, selectedColumn - visibleColumns + 1); |
| 367 | } |
| 368 | } |
| 369 | } |
| 370 | } |