/***
* Excerpted from "Hello, Android! 3e",
* published by The Pragmatic Bookshelf.
* Copyrights apply to this code. It may not be used to create training material,
* courses, books, articles, and the like. Contact us if you are in doubt.
* We make no guarantees that this code is fit for any purpose.
* Visit http://www.pragmaticprogrammer.com/titles/eband3 for more book information.
***/
package com.buuuk.android.ui.touch;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
import com.actionbarsherlock.app.SherlockActivity;
public abstract class TouchActivity extends SherlockActivity {
private static final String TAG = "Touch";
// These matrices will be used to move and zoom image
protected Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
// We can be in one of these 3 states
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// Remember some things for zooming
PointF start = new PointF();
PointF refLineStart = null;
PointF refLineEnd = null;
PointF prevLineStart = null;
PointF prevLineEnd = null;
PointF newStart = new PointF();
PointF newEnd = new PointF();
float oldAngle = 0f;
PointF mid = new PointF();
float oldDist = 1f;
Float mRotateAngle = 0f;
float scaleFactor = 0f;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(getContentView());
//ImageView view = getImageView();
//view.setOnTouchListener(this);
// ...
// Work around a Cupcake bug
matrix.setTranslate(1f, 1f);
//view.setImageMatrix(matrix);
}
public abstract float getMinZoomScale();
public abstract void resetImage(ImageView iv, Drawable draw);
public boolean onTouchEvented(View v, MotionEvent rawEvent) {
WrapMotionEvent event = WrapMotionEvent.wrap(rawEvent);
// ...
ImageView view = (ImageView)v;
// Dump touch event to log
dumpEvent(event);
// Handle touch events here...
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
Log.d(TAG, "mode=DRAG");
mode = DRAG;
break;
case MotionEvent.ACTION_POINTER_DOWN:
oldDist = spacing(event);
Log.d(TAG, "oldDist=" + oldDist);
if (oldDist > 10f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
Log.d(TAG, "mode=ZOOM");
// set the old line if first attempt
refLineStart = new PointF();
refLineEnd = new PointF();
refLineStart.set(event.getX(0), event.getY(0));
refLineEnd.set(event.getX(1), event.getY(1));
prevLineStart = new PointF();
prevLineEnd = new PointF();
prevLineStart.set(event.getX(0), event.getY(0));
prevLineEnd.set(event.getX(1), event.getY(1));
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
Log.d(TAG, "mode=NONE");
refLineStart = null;
refLineEnd = null;
mRotateAngle = 0f;
boolean isScaleChanged=true;
float[] values = new float[9];
view.getImageMatrix().getValues(values);
// if(values[5] < 0 && view.getDrawable().getIntrinsicHeight() < view.getHeight()) {
// matrix.postTranslate(0, - values[5]);
// } else if(view.getDrawable().getIntrinsicHeight() > view.getHeight()) {
// if(values[5] > 0) {
// matrix.postTranslate(0, -values[5]);
// }
// if(values[5] + view.getDrawable().getIntrinsicHeight() < view.getHeight()) {
// matrix.postTranslate(0,
// view.getHeight() - view.getDrawable().getIntrinsicHeight()-values[5]);
// }
// }
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
// ...
matrix.set(savedMatrix);
float betterX = event.getX() - start.x;
float[] values1 = new float[9];
view.getImageMatrix().getValues(values1);
if(values1[0] == getMinZoomScale()) {
betterX = 0;
}
matrix.postTranslate(betterX,
event.getY() - start.y);
}
else if (mode == ZOOM)
{
float newDist = spacing(event);
Log.d(TAG, "newDist=" + newDist);
if (newDist > 10f) {
matrix.set(savedMatrix);
float scale = newDist / oldDist;
Log.v("Scaling","Scale: "+scale);
Matrix test = new Matrix(matrix);
// test scale matrix
test.postScale(scale, scale, mid.x, mid.y);
float[] svalues = new float[9];
test.getValues(svalues);
//if(svalues[0]>=getMinZoomScale())
matrix.postScale(scale, scale, mid.x, mid.y);
//else
// matrix.setScale(getMinZoomScale(), getMinZoomScale(), mid.x, mid.y);
// get the latest line
newStart.set(event.getX(0), event.getY(0));
newEnd.set(event.getX(1), event.getY(1));
float angle = new Float(angleBetweenLinesInRadians(prevLineStart,prevLineEnd,newStart,newEnd)).floatValue();
// calculate the angle difference and do rotation
mRotateAngle = mRotateAngle + angle;
//matrix.postRotate( mRotateAngle ,mid.x, mid.y );
// record the old line value
prevLineStart.set(event.getX(0), event.getY(0));
prevLineEnd.set(event.getX(1), event.getY(1));
}
}
break;
}
Log.v("Matrix","scale matrix: "+matrix);
view.setImageMatrix(matrix);
//System.gc();
return true; // indicate event was handled
}
public double angleBetweenLinesInRadians( PointF line1Start, PointF line1End, PointF line2Start, PointF line2End) {
float a = line1End.x - line1Start.x;
float b = line1End.y - line1Start.y;
float c = line2End.x - line2Start.x;
float d = line2End.y - line2Start.y;
float line1Slope = (line1End.y - line1Start.y) / (line1End.x - line1Start.x);
float line2Slope = (line2End.y - line2Start.y) / (line2End.x - line2Start.x);
double subf = ((a*c) + (b*d)) / ((Math.sqrt(a*a + b*b)) * (Math.sqrt(c*c + d*d)));
subf = subf>1?1:subf;
subf = subf<-1?-1:subf;
double degs = Math.acos(subf);
double result = (line2Slope > line1Slope) ? degs*180/3.142 : -degs*180/3.142;
return result;
}
/** Show an event in the LogCat view, for debugging */
private void dumpEvent(WrapMotionEvent event) {
// ...
String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
"POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
StringBuilder sb = new StringBuilder();
int action = event.getAction();
int actionCode = action & MotionEvent.ACTION_MASK;
sb.append("event ACTION_").append(names[actionCode]);
if (actionCode == MotionEvent.ACTION_POINTER_DOWN
|| actionCode == MotionEvent.ACTION_POINTER_UP) {
sb.append("(pid ").append(
action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
sb.append(")");
}
sb.append("[");
for (int i = 0; i < event.getPointerCount(); i++) {
sb.append("#").append(i);
sb.append("(pid ").append(event.getPointerId(i));
sb.append(")=").append((int) event.getX(i));
sb.append(",").append((int) event.getY(i));
if (i + 1 < event.getPointerCount())
sb.append(";");
}
sb.append("]");
Log.d(TAG, sb.toString());
}
/** Determine the space between the first two fingers */
private float spacing(WrapMotionEvent event) {
// ...
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
/** Calculate the mid point of the first two fingers */
private void midPoint(PointF point, WrapMotionEvent event) {
// ...
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
}