src/jexer/TDirectoryList.java

   1 /**
   2  * Jexer - Java Text User Interface
   3  *
   4  * License: LGPLv3 or later
   5  *
   6  * This module is licensed under the GNU Lesser General Public License
   7  * Version 3.  Please see the file "COPYING" in this directory for more
   8  * information about the GNU Lesser General Public License Version 3.
   9  *
  10  *     Copyright (C) 2015  Kevin Lamonte
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public License
  14  * as published by the Free Software Foundation; either version 3 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this program; if not, see
  24  * http://www.gnu.org/licenses/, or write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  26  * 02110-1301 USA
  27  *
  28  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  29  * @version 1
  30  */
  31 package jexer;
  32
  33 import java.io.File;
  34 import java.util.ArrayList;
  35 import java.util.List;
  36
  37 import jexer.bits.CellAttributes;
  38 import jexer.event.TKeypressEvent;
  39 import jexer.event.TMouseEvent;
  40 import static jexer.TKeypress.*;
  41
  42 /**
  43  * TDirectoryList shows the files within a directory.
  44  */
  45 public class TDirectoryList extends TWidget {
  46
  47     /**
  48      * Files in the directory.
  49      */
  50     private List<File> files;
  51
  52     /**
  53      * Selected file.
  54      */
  55     private int selectedFile = -1;
  56
  57     /**
  58      * Root path containing files to display.
  59      */
  60     public File path;
  61
  62     /**
  63      * Vertical scrollbar.
  64      */
  65     private TVScroller vScroller;
  66
  67     /**
  68      * Horizontal scrollbar.
  69      */
  70     private THScroller hScroller;
  71
  72     /**
  73      * Maximum width of a single line.
  74      */
  75     private int maxLineWidth;
  76
  77     /**
  78      * The action to perform when the user selects an item.
  79      */
  80     private TAction action = null;
  81
  82     /**
  83      * Perform user selection action.
  84      */
  85     public void dispatch() {
  86         assert (selectedFile >= 0);
  87         assert (selectedFile < files.size());
  88         if (action != null) {
  89             action.DO();
  90         }
  91     }
  92
  93     /**
  94      * Format one of the entries for drawing on the screen.
  95      *
  96      * @param index index into files
  97      * @return the line to draw
  98      */
  99     private String renderFile(int index) {
 100         File file = files.get(index);
 101         String name = file.getName();
 102         if (name.length() > 20) {
 103             name = name.substring(0, 17) + "...";
 104         }
 105         return String.format("%-20s %5dk", name, (file.length() / 1024));
 106     }
 107
 108     /**
 109      * Resize for a new width/height.
 110      */
 111     public void reflow() {
 112
 113         // Reset the lines
 114         selectedFile = -1;
 115         maxLineWidth = 0;
 116         files.clear();
 117
 118         // Build a list of files in this directory
 119         File [] newFiles = path.listFiles();
 120         for (int i = 0; i < newFiles.length; i++) {
 121             if (newFiles[i].getName().startsWith(".")) {
 122                 continue;
 123             }
 124             if (newFiles[i].isDirectory()) {
 125                 continue;
 126             }
 127             files.add(newFiles[i]);
 128         }
 129
 130         for (int i = 0; i < files.size(); i++) {
 131             String line = renderFile(i);
 132             if (line.length() > maxLineWidth) {
 133                 maxLineWidth = line.length();
 134             }
 135         }
 136
 137         // Start at the top
 138         if (vScroller == null) {
 139             vScroller = new TVScroller(this, getWidth() - 1, 0,
 140                 getHeight() - 1);
 141         } else {
 142             vScroller.setX(getWidth() - 1);
 143             vScroller.setHeight(getHeight() - 1);
 144         }
 145         vScroller.setBottomValue(files.size() - getHeight() - 1);
 146         vScroller.setTopValue(0);
 147         vScroller.setValue(0);
 148         if (vScroller.getBottomValue() < 0) {
 149             vScroller.setBottomValue(0);
 150         }
 151         vScroller.setBigChange(getHeight() - 1);
 152
 153         // Start at the left
 154         if (hScroller == null) {
 155             hScroller = new THScroller(this, 0, getHeight() - 1,
 156                 getWidth() - 1);
 157         } else {
 158             hScroller.setY(getHeight() - 1);
 159             hScroller.setWidth(getWidth() - 1);
 160         }
 161         hScroller.setRightValue(maxLineWidth - getWidth() + 1);
 162         hScroller.setLeftValue(0);
 163         hScroller.setValue(0);
 164         if (hScroller.getRightValue() < 0) {
 165             hScroller.setRightValue(0);
 166         }
 167         hScroller.setBigChange(getWidth() - 1);
 168     }
 169
 170     /**
 171      * Public constructor.
 172      *
 173      * @param parent parent widget
 174      * @param path directory path, must be a directory
 175      * @param x column relative to parent
 176      * @param y row relative to parent
 177      * @param width width of text area
 178      * @param height height of text area
 179      */
 180     public TDirectoryList(final TWidget parent, final String path, final int x,
 181         final int y, final int width, final int height) {
 182
 183         this(parent, path, x, y, width, height, null);
 184     }
 185
 186     /**
 187      * Public constructor.
 188      *
 189      * @param parent parent widget
 190      * @param path directory path, must be a directory
 191      * @param x column relative to parent
 192      * @param y row relative to parent
 193      * @param width width of text area
 194      * @param height height of text area
 195      * @param action action to perform when an item is selected
 196      */
 197     public TDirectoryList(final TWidget parent, final String path, final int x,
 198         final int y, final int width, final int height, final TAction action) {
 199
 200         this.path   = new File(path);
 201         this.action = action;
 202         files = new ArrayList<File>();
 203         reflow();
 204     }
 205
 206     /**
 207      * Draw the files list.
 208      */
 209     @Override
 210     public void draw() {
 211         CellAttributes color = null;
 212         int begin = vScroller.getValue();
 213         int topY = 0;
 214         for (int i = begin; i < files.size() - 1; i++) {
 215             String line = renderFile(i);
 216             if (hScroller.getValue() < line.length()) {
 217                 line = line.substring(hScroller.getValue());
 218             } else {
 219                 line = "";
 220             }
 221             if (i == selectedFile) {
 222                 color = getTheme().getColor("tdirectorylist.selected");
 223             } else if (isAbsoluteActive()) {
 224                 color = getTheme().getColor("tdirectorylist");
 225             } else {
 226                 color = getTheme().getColor("tdirectorylist.inactive");
 227             }
 228             String formatString = "%-" + Integer.toString(getWidth() - 1) + "s";
 229             getScreen().putStringXY(0, topY, String.format(formatString, line),
 230                     color);
 231             topY++;
 232             if (topY >= getHeight() - 1) {
 233                 break;
 234             }
 235         }
 236
 237         // Pad the rest with blank lines
 238         for (int i = topY; i < getHeight() - 1; i++) {
 239             getScreen().hLineXY(0, i, getWidth() - 1, ' ', color);
 240         }
 241     }
 242
 243     /**
 244      * Handle mouse press events.
 245      *
 246      * @param mouse mouse button press event
 247      */
 248     @Override
 249     public void onMouseDown(final TMouseEvent mouse) {
 250         if (mouse.isMouseWheelUp()) {
 251             vScroller.decrement();
 252             return;
 253         }
 254         if (mouse.isMouseWheelDown()) {
 255             vScroller.increment();
 256             return;
 257         }
 258
 259         if ((mouse.getX() < getWidth() - 1)
 260             && (mouse.getY() < getHeight() - 1)) {
 261             if (vScroller.getValue() + mouse.getY() < files.size()) {
 262                 selectedFile = vScroller.getValue() + mouse.getY();
 263             }
 264             path = files.get(selectedFile);
 265             dispatch();
 266             return;
 267         }
 268
 269         // Pass to children
 270         super.onMouseDown(mouse);
 271     }
 272
 273     /**
 274      * Handle mouse release events.
 275      *
 276      * @param mouse mouse button release event
 277      */
 278     @Override
 279     public void onMouseUp(final TMouseEvent mouse) {
 280         // Pass to children
 281         super.onMouseDown(mouse);
 282     }
 283
 284     /**
 285      * Handle keystrokes.
 286      *
 287      * @param keypress keystroke event
 288      */
 289     @Override
 290     public void onKeypress(final TKeypressEvent keypress) {
 291         if (keypress.equals(kbLeft)) {
 292             hScroller.decrement();
 293         } else if (keypress.equals(kbRight)) {
 294             hScroller.increment();
 295         } else if (keypress.equals(kbUp)) {
 296             vScroller.decrement();
 297         } else if (keypress.equals(kbDown)) {
 298             vScroller.increment();
 299         } else if (keypress.equals(kbPgUp)) {
 300             vScroller.bigDecrement();
 301         } else if (keypress.equals(kbPgDn)) {
 302             vScroller.bigIncrement();
 303         } else if (keypress.equals(kbHome)) {
 304             vScroller.toTop();
 305         } else if (keypress.equals(kbEnd)) {
 306             vScroller.toBottom();
 307         } else {
 308             // Pass other keys (tab etc.) on
 309             super.onKeypress(keypress);
 310         }
 311     }
 312
 313 }