I am using ViewPager in my app to create a slider for sliding images. Everthing is working fine except i have to zoom image on double tap. But double tap is not working on ViewPager. I tried many solution but invain. Any help appreciated.
Thanks
use this class for image pinch to zoom and double tap zoom
import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;
import android.widget.ImageView;
public class TouchImageView extends ImageView {
Matrix matrix = 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;
//static NonSwipeableViewPager PagerLeft;
// Remember some things for zooming
PointF last = new PointF();
PointF start = new PointF();
float minScale = 1f;
float maxScale = 3f;
float[] m;
static boolean b =false, c= false;
float redundantXSpace, redundantYSpace;
float width, height;
static final int CLICK = 3;
float saveScale = 1f;
float right, bottom, origWidth, origHeight, bmWidth, bmHeight;
ScaleGestureDetector mScaleDetector;
Context context;
ViewGroup vp;
public TouchImageView(Context context) {
super(context);
sharedConstructing(context);
}
public TouchImageView(Context context, AttributeSet attrs) {
super(context, attrs);
sharedConstructing(context);
}
public void setChild(ViewGroup vp) {
this.vp = vp;
}
private void sharedConstructing(Context context) {
super.setClickable(true);
this.context = context;
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
matrix.setTranslate(1f, 1f);
m = new float[9];
setImageMatrix(matrix);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(new OnTouchListener() {
@SuppressWarnings("deprecation")
@Override
public boolean onTouch(View v, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
/*Log.v("log_tag", event.getX()+" matrix "
+ x);*/
PointF curr = new PointF(event.getX(), event.getY());
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
TouchImageView.b = false;
Log.v("event","ACTION_DOWN");
last.set(event.getX(), event.getY());
start.set(last);
mode = DRAG;
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
float deltaX = curr.x - last.x;
float deltaY = curr.y - last.y;
float scaleWidth = Math.round(origWidth * saveScale);
float scaleHeight = Math.round(origHeight * saveScale);
if (scaleWidth < width) {
deltaX = 0;
if (y + deltaY > 0){
TouchImageView.b = true;
Log.v("event","ACTION_MOVE scaleWidth < width y + deltaY > 0");
deltaY = -y;
}
else if (y + deltaY < -bottom){
TouchImageView.b = false;
Log.v("event","else ACTION_MOVE scaleWidth < width y + deltaY < -bottom");
deltaY = -(y + bottom);
}else{
TouchImageView.b = false;
}
} else if (scaleHeight < height) {
deltaY = 0;
if (x + deltaX > 0){
TouchImageView.b = true;
Log.v("event","ACTION_MOVE scaleWidth < height x + deltaX > 0");
deltaX = -x;
}
else if (x + deltaX < -right){
TouchImageView.b = true;
Log.v("event","ACTION_MOVE scaleWidth < height x + deltaX < -right");
deltaX = -(x + right);
}else{
TouchImageView.b = false;
}
}else {
if (x + deltaX > 0){
TouchImageView.b = true;
Log.v("event","scaleWidth > width");
deltaX = -x;
}
else if (x + deltaX < -right){
TouchImageView.b = true;
Log.v("event","else scaleWidth > width");
deltaX = -(x + right);
}
else{
TouchImageView.b = true;
}
if (y + deltaY > 0){
TouchImageView.b = true;
Log.v("event","y + deltaY");
deltaY = -y;
}
else if (y + deltaY < -bottom){
TouchImageView.b = true;
Log.v("event","y + deltaY < -bottom");
deltaY = -(y + bottom);
}else{
TouchImageView.b = false;
}
}
/*Log.v("log_tag",height + " matrix "
+ (int) getHeightFromMatrix(matrix, TouchImageView.this));*/
matrix.postTranslate(deltaX, deltaY);
last.set(curr.x, curr.y);
}
break;
case MotionEvent.ACTION_UP:
Log.v("event","ACTION_UP");
TouchImageView.b = true;
mode = NONE;
int xDiff = (int) Math.abs(curr.x - start.x);
int yDiff = (int) Math.abs(curr.y - start.y);
if (xDiff < CLICK && yDiff < CLICK){
Log.v("event","ACTION_UP xDiff < CLICK && yDiff < CLICK");
performClick();
}
break;
case MotionEvent.ACTION_POINTER_UP:
//TouchImageView.b = false;
Log.v("event","ACTION_POINTER_UP");
mode = NONE;
break;
case MotionEvent.ACTION_POINTER_3_DOWN:
Log.v("event","ACTION_HOVER_MOVE");
break;
}
/*getLayoutParams().height = (int) getWidthFromMatrix(matrix,
TouchImageView.this);
getLayoutParams().width = (int) getHeightFromMatrix(matrix,
TouchImageView.this);*/
setImageMatrix(matrix);
invalidate();
return true;
}
});
}
@Override
public void setImageBitmap(Bitmap bm) {
super.setImageBitmap(bm);
if (bm != null) {
bmWidth = bm.getWidth();
bmHeight = bm.getHeight();
}
}
public void setMaxZoom(float x) {
maxScale = x;
}
private class ScaleListener extends
ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
mode = ZOOM;
return true;
}
@SuppressLint("NewApi")
@TargetApi(8)
@Override
public boolean onScale(ScaleGestureDetector detector) {
float mScaleFactor = (float) Math.min(
Math.max(.95f, detector.getScaleFactor()), 1.05);
float origScale = saveScale;
saveScale *= mScaleFactor;
if (saveScale > maxScale) {
saveScale = maxScale;
mScaleFactor = maxScale / origScale;
} else if (saveScale < minScale) {
saveScale = minScale;
mScaleFactor = minScale / origScale;
}
right = width * saveScale - width
- (2 * redundantXSpace * saveScale);
bottom = height * saveScale - height
- (2 * redundantYSpace * saveScale);
if (origWidth * saveScale <= width
|| origHeight * saveScale <= height) {
matrix.postScale(mScaleFactor, mScaleFactor, width / 2,
height / 2);
if (mScaleFactor < 1) {
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
if (mScaleFactor < 1) {
if (Math.round(origWidth * saveScale) < width) {
if (y < -bottom)
matrix.postTranslate(0, -(y + bottom));
else if (y > 0)
matrix.postTranslate(0, -y);
} else {
if (x < -right)
matrix.postTranslate(-(x + right), 0);
else if (x > 0)
matrix.postTranslate(-x, 0);
}
}
}
} else {
matrix.postScale(mScaleFactor, mScaleFactor,
detector.getFocusX(), detector.getFocusY());
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
if (mScaleFactor < 1) {
if (x < -right)
matrix.postTranslate(-(x + right), 0);
else if (x > 0)
matrix.postTranslate(-x, 0);
if (y < -bottom)
matrix.postTranslate(0, -(y + bottom));
else if (y > 0)
matrix.postTranslate(0, -y);
}
}
return true;
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
width = MeasureSpec.getSize(widthMeasureSpec);
height = MeasureSpec.getSize(heightMeasureSpec);
// Fit to screen.
float scale;
float scaleX = (float) width / (float) bmWidth;
float scaleY = (float) height / (float) bmHeight;
scale = Math.min(scaleX, scaleY);
matrix.setScale(scale, scale);
setImageMatrix(matrix);
saveScale = 1f;
// Center the image
redundantYSpace = (float) height - (scale * (float) bmHeight);
redundantXSpace = (float) width - (scale * (float) bmWidth);
redundantYSpace /= (float) 2;
redundantXSpace /= (float) 2;
matrix.postTranslate(redundantXSpace, redundantYSpace);
origWidth = width - 2 * redundantXSpace;
origHeight = height - 2 * redundantYSpace;
right = width * saveScale - width - (2 * redundantXSpace * saveScale);
bottom = height * saveScale - height
- (2 * redundantYSpace * saveScale);
setImageMatrix(matrix);
}
/*public static void setPager(NonSwipeableViewPager pagerLeft) {
PagerLeft = pagerLeft;
}*/
}
In your pager adapter just do it
TouchImageView image_view=(TouchImageView)findViewById(R.id.your_image);