android/source/src/java/org/libreoffice/canvas/GraphicSelectionHandle.java

   1 /* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9 package org.libreoffice.canvas;
  10
  11 import android.graphics.Canvas;
  12 import android.graphics.Color;
  13 import android.graphics.Paint;
  14 import android.graphics.PointF;
  15 import android.graphics.RectF;
  16
  17 /**
  18  * This class is responsible to draw the selection handles, track the handle
  19  * position and perform a hit test to determine if the selection handle was
  20  * touched.
  21  */
  22 public class GraphicSelectionHandle extends CommonCanvasElement {
  23     /**
  24      * The factor used to inflate the hit area.
  25      */
  26     private static final float HIT_AREA_INFLATE_FACTOR = 1.75f;
  27
  28     private final HandlePosition mHandlePosition;
  29     public PointF mPosition = new PointF();
  30     private float mRadius = 20.0f;
  31     private Paint mStrokePaint = new Paint();
  32     private Paint mFillPaint = new Paint();
  33     private Paint mSelectedFillPaint = new Paint();
  34     private RectF mHitRect = new RectF();
  35     private boolean mSelected = false;
  36
  37     /**
  38      * Construct the handle - set the handle position on the selection.
  39      * @param position - the handle position on the selection
  40      */
  41     public GraphicSelectionHandle(HandlePosition position) {
  42         mHandlePosition = position;
  43
  44         mStrokePaint.setStyle(Paint.Style.STROKE);
  45         mStrokePaint.setColor(Color.GRAY);
  46         mStrokePaint.setStrokeWidth(3);
  47         mStrokePaint.setAntiAlias(true);
  48
  49         mFillPaint.setStyle(Paint.Style.FILL);
  50         mFillPaint.setColor(Color.WHITE);
  51         mFillPaint.setAlpha(200);
  52         mFillPaint.setAntiAlias(true);
  53
  54         mSelectedFillPaint.setStyle(Paint.Style.FILL);
  55         mSelectedFillPaint.setColor(Color.GRAY);
  56         mSelectedFillPaint.setAlpha(200);
  57         mSelectedFillPaint.setAntiAlias(true);
  58     }
  59
  60     /**
  61      * The position of the handle.
  62      * @return
  63      */
  64     public HandlePosition getHandlePosition() {
  65         return mHandlePosition;
  66     }
  67
  68     /**
  69      * Draws the handle to the canvas.
  70      *
  71      * @see org.libreoffice.canvas.CanvasElement#draw(android.graphics.Canvas)
  72      */
  73     @Override
  74     public void onDraw(Canvas canvas) {
  75         if (mSelected) {
  76             drawFilledCircle(canvas, mPosition.x, mPosition.y, mRadius, mStrokePaint, mSelectedFillPaint);
  77         } else {
  78             drawFilledCircle(canvas, mPosition.x, mPosition.y, mRadius, mStrokePaint, mFillPaint);
  79         }
  80     }
  81
  82     /**
  83      * Draw a filled and stroked circle to the canvas.
  84      */
  85     private void drawFilledCircle(Canvas canvas, float x, float y, float radius, Paint strokePaint, Paint fillPaint) {
  86         canvas.drawCircle(x, y, radius, fillPaint);
  87         canvas.drawCircle(x, y, radius, strokePaint);
  88     }
  89
  90     /**
  91      * Viewport has changed, reposition the handle to the input coordinates.
  92      */
  93     public void reposition(float x, float y) {
  94         mPosition.x = x;
  95         mPosition.y = y;
  96
  97         // inflate the radius by HIT_AREA_INFLATE_FACTOR
  98         float inflatedRadius = mRadius * HIT_AREA_INFLATE_FACTOR;
  99
 100         // reposition the hit area rectangle
 101         mHitRect.left = mPosition.x - inflatedRadius;
 102         mHitRect.right = mPosition.x + inflatedRadius;
 103         mHitRect.top = mPosition.y - inflatedRadius;
 104         mHitRect.bottom = mPosition.y + inflatedRadius;
 105     }
 106
 107     /**
 108      * Hit test for the handle.
 109      * @see org.libreoffice.canvas.CanvasElement#draw(android.graphics.Canvas)
 110      */
 111     @Override
 112     public boolean onHitTest(float x, float y) {
 113         return mHitRect.contains(x, y);
 114     }
 115
 116     /**
 117      * Mark the handle as selected.
 118      */
 119     public void select() {
 120         mSelected = true;
 121     }
 122
 123     /**
 124      * Reset the selection for the handle.
 125      */
 126     public void reset() {
 127         mSelected = false;
 128     }
 129
 130     /**
 131      * All possible handle positions. The selection rectangle has 8 possible
 132      * handles.
 133      */
 134     public enum HandlePosition {
 135         TOP_LEFT,
 136         TOP,
 137         TOP_RIGHT,
 138         RIGHT,
 139         BOTTOM_RIGHT,
 140         BOTTOM,
 141         BOTTOM_LEFT,
 142         LEFT
 143     }
 144 }
 145
 146 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */