1 |
package com.caddi.android.caddipictureupload; |
2 |
|
3 |
import android.content.Context; |
4 |
import android.graphics.Bitmap; |
5 |
import android.graphics.Matrix; |
6 |
import android.graphics.PointF; |
7 |
import android.util.AttributeSet; |
8 |
import android.view.MotionEvent; |
9 |
import android.view.ScaleGestureDetector; |
10 |
import android.view.View; |
11 |
import android.widget.ImageView; |
12 |
|
13 |
/** |
14 |
* Copied from http://stackoverflow.com/questions/6650398/android-imageview-zoom-in-and-zoom-out |
15 |
*/ |
16 |
public class ZoomableImageView extends ImageView |
17 |
{ |
18 |
Matrix matrix = new Matrix(); |
19 |
|
20 |
static final int NONE = 0; |
21 |
static final int DRAG = 1; |
22 |
static final int ZOOM = 2; |
23 |
static final int CLICK = 3; |
24 |
int mode = NONE; |
25 |
|
26 |
PointF last = new PointF(); |
27 |
PointF start = new PointF(); |
28 |
float minScale = 1f; |
29 |
float maxScale = 4f; |
30 |
float[] m; |
31 |
|
32 |
float redundantXSpace, redundantYSpace; |
33 |
float width, height; |
34 |
float saveScale = 1f; |
35 |
float right, bottom, origWidth, origHeight, bmWidth, bmHeight; |
36 |
|
37 |
ScaleGestureDetector mScaleDetector; |
38 |
Context context; |
39 |
|
40 |
public ZoomableImageView(Context context, AttributeSet attr) |
41 |
{ |
42 |
super(context, attr); |
43 |
super.setClickable(true); |
44 |
this.context = context; |
45 |
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener()); |
46 |
matrix.setTranslate(1f, 1f); |
47 |
m = new float[9]; |
48 |
setImageMatrix(matrix); |
49 |
setScaleType(ScaleType.MATRIX); |
50 |
|
51 |
setOnTouchListener(new OnTouchListener() |
52 |
{ |
53 |
|
54 |
@Override |
55 |
public boolean onTouch(View v, MotionEvent event) |
56 |
{ |
57 |
mScaleDetector.onTouchEvent(event); |
58 |
|
59 |
matrix.getValues(m); |
60 |
float x = m[Matrix.MTRANS_X]; |
61 |
float y = m[Matrix.MTRANS_Y]; |
62 |
PointF curr = new PointF(event.getX(), event.getY()); |
63 |
|
64 |
switch (event.getAction()) |
65 |
{ |
66 |
//when one finger is touching |
67 |
//set the mode to DRAG |
68 |
case MotionEvent.ACTION_DOWN: |
69 |
last.set(event.getX(), event.getY()); |
70 |
start.set(last); |
71 |
mode = DRAG; |
72 |
break; |
73 |
//when two fingers are touching |
74 |
//set the mode to ZOOM |
75 |
case MotionEvent.ACTION_POINTER_DOWN: |
76 |
last.set(event.getX(), event.getY()); |
77 |
start.set(last); |
78 |
mode = ZOOM; |
79 |
break; |
80 |
//when a finger moves |
81 |
//If mode is applicable move image |
82 |
case MotionEvent.ACTION_MOVE: |
83 |
//if the mode is ZOOM or |
84 |
//if the mode is DRAG and already zoomed |
85 |
if (mode == ZOOM || (mode == DRAG && saveScale > minScale)) |
86 |
{ |
87 |
float deltaX = curr.x - last.x;// x difference |
88 |
float deltaY = curr.y - last.y;// y difference |
89 |
float scaleWidth = Math.round(origWidth * saveScale);// width after applying current scale |
90 |
float scaleHeight = Math.round(origHeight * saveScale);// height after applying current scale |
91 |
//if scaleWidth is smaller than the views width |
92 |
//in other words if the image width fits in the view |
93 |
//limit left and right movement |
94 |
if (scaleWidth < width) |
95 |
{ |
96 |
deltaX = 0; |
97 |
if (y + deltaY > 0) |
98 |
deltaY = -y; |
99 |
else if (y + deltaY < -bottom) |
100 |
deltaY = -(y + bottom); |
101 |
} |
102 |
//if scaleHeight is smaller than the views height |
103 |
//in other words if the image height fits in the view |
104 |
//limit up and down movement |
105 |
else if (scaleHeight < height) |
106 |
{ |
107 |
deltaY = 0; |
108 |
if (x + deltaX > 0) |
109 |
deltaX = -x; |
110 |
else if (x + deltaX < -right) |
111 |
deltaX = -(x + right); |
112 |
} |
113 |
//if the image doesnt fit in the width or height |
114 |
//limit both up and down and left and right |
115 |
else |
116 |
{ |
117 |
if (x + deltaX > 0) |
118 |
deltaX = -x; |
119 |
else if (x + deltaX < -right) |
120 |
deltaX = -(x + right); |
121 |
|
122 |
if (y + deltaY > 0) |
123 |
deltaY = -y; |
124 |
else if (y + deltaY < -bottom) |
125 |
deltaY = -(y + bottom); |
126 |
} |
127 |
//move the image with the matrix |
128 |
matrix.postTranslate(deltaX, deltaY); |
129 |
//set the last touch location to the current |
130 |
last.set(curr.x, curr.y); |
131 |
} |
132 |
break; |
133 |
//first finger is lifted |
134 |
case MotionEvent.ACTION_UP: |
135 |
mode = NONE; |
136 |
int xDiff = (int) Math.abs(curr.x - start.x); |
137 |
int yDiff = (int) Math.abs(curr.y - start.y); |
138 |
if (xDiff < CLICK && yDiff < CLICK) |
139 |
performClick(); |
140 |
break; |
141 |
// second finger is lifted |
142 |
case MotionEvent.ACTION_POINTER_UP: |
143 |
mode = NONE; |
144 |
break; |
145 |
} |
146 |
setImageMatrix(matrix); |
147 |
invalidate(); |
148 |
return true; |
149 |
} |
150 |
|
151 |
}); |
152 |
} |
153 |
|
154 |
@Override |
155 |
public void setImageBitmap(Bitmap bm) |
156 |
{ |
157 |
super.setImageBitmap(bm); |
158 |
bmWidth = bm.getWidth(); |
159 |
bmHeight = bm.getHeight(); |
160 |
} |
161 |
|
162 |
public void setMaxZoom(float x) |
163 |
{ |
164 |
maxScale = x; |
165 |
} |
166 |
|
167 |
private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener |
168 |
{ |
169 |
|
170 |
@Override |
171 |
public boolean onScaleBegin(ScaleGestureDetector detector) |
172 |
{ |
173 |
mode = ZOOM; |
174 |
return true; |
175 |
} |
176 |
|
177 |
@Override |
178 |
public boolean onScale(ScaleGestureDetector detector) |
179 |
{ |
180 |
float mScaleFactor = detector.getScaleFactor(); |
181 |
float origScale = saveScale; |
182 |
saveScale *= mScaleFactor; |
183 |
if (saveScale > maxScale) |
184 |
{ |
185 |
saveScale = maxScale; |
186 |
mScaleFactor = maxScale / origScale; |
187 |
} |
188 |
else if (saveScale < minScale) |
189 |
{ |
190 |
saveScale = minScale; |
191 |
mScaleFactor = minScale / origScale; |
192 |
} |
193 |
right = width * saveScale - width - (2 * redundantXSpace * saveScale); |
194 |
bottom = height * saveScale - height - (2 * redundantYSpace * saveScale); |
195 |
if (origWidth * saveScale <= width || origHeight * saveScale <= height) |
196 |
{ |
197 |
matrix.postScale(mScaleFactor, mScaleFactor, width / 2, height / 2); |
198 |
if (mScaleFactor < 1) |
199 |
{ |
200 |
matrix.getValues(m); |
201 |
float x = m[Matrix.MTRANS_X]; |
202 |
float y = m[Matrix.MTRANS_Y]; |
203 |
if (mScaleFactor < 1) |
204 |
{ |
205 |
if (Math.round(origWidth * saveScale) < width) |
206 |
{ |
207 |
if (y < -bottom) |
208 |
matrix.postTranslate(0, -(y + bottom)); |
209 |
else if (y > 0) |
210 |
matrix.postTranslate(0, -y); |
211 |
} |
212 |
else |
213 |
{ |
214 |
if (x < -right) |
215 |
matrix.postTranslate(-(x + right), 0); |
216 |
else if (x > 0) |
217 |
matrix.postTranslate(-x, 0); |
218 |
} |
219 |
} |
220 |
} |
221 |
} |
222 |
else |
223 |
{ |
224 |
matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY()); |
225 |
matrix.getValues(m); |
226 |
float x = m[Matrix.MTRANS_X]; |
227 |
float y = m[Matrix.MTRANS_Y]; |
228 |
if (mScaleFactor < 1) { |
229 |
if (x < -right) |
230 |
matrix.postTranslate(-(x + right), 0); |
231 |
else if (x > 0) |
232 |
matrix.postTranslate(-x, 0); |
233 |
if (y < -bottom) |
234 |
matrix.postTranslate(0, -(y + bottom)); |
235 |
else if (y > 0) |
236 |
matrix.postTranslate(0, -y); |
237 |
} |
238 |
} |
239 |
return true; |
240 |
} |
241 |
} |
242 |
|
243 |
@Override |
244 |
protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec) |
245 |
{ |
246 |
super.onMeasure(widthMeasureSpec, heightMeasureSpec); |
247 |
width = View.MeasureSpec.getSize(widthMeasureSpec); |
248 |
height = View.MeasureSpec.getSize(heightMeasureSpec); |
249 |
//Fit to screen. |
250 |
float scale; |
251 |
float scaleX = width / bmWidth; |
252 |
float scaleY = height / bmHeight; |
253 |
scale = Math.min(scaleX, scaleY); |
254 |
matrix.setScale(scale, scale); |
255 |
setImageMatrix(matrix); |
256 |
saveScale = 1f; |
257 |
|
258 |
// Center the image |
259 |
redundantYSpace = height - (scale * bmHeight) ; |
260 |
redundantXSpace = width - (scale * bmWidth); |
261 |
redundantYSpace /= 2; |
262 |
redundantXSpace /= 2; |
263 |
|
264 |
matrix.postTranslate(redundantXSpace, redundantYSpace); |
265 |
|
266 |
origWidth = width - 2 * redundantXSpace; |
267 |
origHeight = height - 2 * redundantYSpace; |
268 |
right = width * saveScale - width - (2 * redundantXSpace * saveScale); |
269 |
bottom = height * saveScale - height - (2 * redundantYSpace * saveScale); |
270 |
setImageMatrix(matrix); |
271 |
} |
272 |
} |