我正在尝试实现双击和缩放缩放活动。我为第一个编写了一些代码，但似乎没有用（我现在只能使用android模拟器进行eclipse。所以我不确定我的结果是否正确）
无论如何，我无法理解我做错了什么。我肯定忘了什么。
这是我的代码：
public class ImageZoomView extends View implements OnGestureListener {
private static final int SCALING_FACTOR = 50;
private final int LANDSCAPE = 1;
private GestureDetector gestureDetector;
private Drawable image = null;
private int scalefactor = 0;
private int orientation;
private int zoomCtr = 0;
private long lastTouchTime = 0;
private int winX, winY, imageX, imageY, scrollX = 0, scrollY = 0, left,
top, bottom, right;
public ImageZoomView(Context context, int orientation) {
super(context);
setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
this.orientation = orientation;
gestureDetector = new GestureDetector(this);
}
public void setImage(Drawable bitmap, Activity activity) {
image = bitmap;
imageSetting(activity);
}
public void setImage(Bitmap bitmap, Activity activity) {
image = new BitmapDrawable(bitmap).getCurrent();
imageSetting(activity);
}
/**
* Works in both landscape and portrait mode.
*/
private void imageSetting(Activity activity) {
scrollX = scrollY = 0;
scalefactor = 0;
imageX = winX = activity.getWindow().getWindowManager()
.getDefaultDisplay().getWidth();
imageY = winY = activity.getWindow().getWindowManager()
.getDefaultDisplay().getHeight();
if (orientation == LANDSCAPE) {
imageX = 3 * imageY / 4;
}
calculatePos();
}
public void calculatePos() {
int tempx, tempy;
tempx = imageX + imageX * scalefactor / 100;
tempy = imageY + imageY * scalefactor / 100;
left = (winX - tempx) / 2;
top = (winY - tempy) / 2;
right = (winX + tempx) / 2;
bottom = (winY + tempy) / 2;
invalidate();
}
/**
* Redraws the bitmap when zoomed or scrolled.
*/
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (image == null)
return;
image.setBounds(left + scrollX, top + scrollY, right + scrollX, bottom
+ scrollY);
image.draw(canvas);
}
public void zoomIn() {
scalefactor += SCALING_FACTOR;
calculatePos();
}
public void zoomOut() {
if (scalefactor == 0)
return;
scrollX = scrollY = 0;
scalefactor -= SCALING_FACTOR;
calculatePos();
}
public void scroll(int x, int y) {
scrollX += x / 5;
scrollY += y / 5;
if (scrollX + left > 0) {
scrollX = 0 - left;
} else if (scrollX + right < winX) {
scrollX = winX - right;
}
if (scrollY + top > 0) {
scrollY = 0 - top;
} else if (scrollY + bottom < winY) {
scrollY = winY - bottom;
}
invalidate();
}
@Override
public boolean onTouchEvent(MotionEvent me) {
boolean onTouchEvent = gestureDetector.onTouchEvent(me);
return onTouchEvent;
}
@Override
public boolean onDown(MotionEvent arg0) {
long thisTime = arg0.getEventTime();
if (thisTime - lastTouchTime < 250) {
lastTouchTime = -1;
onDoubleTap();
return true;
}
lastTouchTime = thisTime;
return true;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
float distanceY) {
if (zoomCtr == 0)
return false;
scroll((int) (e2.getX() - e1.getX()), (int) (e2.getY() - e1.getY()));
return true;
}
private void onDoubleTap() {
if (zoomCtr == 0) {
zoomCtr++;
zoomIn();
return;
}
zoomCtr--;
zoomOut();
}
}
这就是我称之为活动的地方：
public class FullScreenPhoto extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_full_screen_photo);
Intent intent = getIntent();
String path = intent.getStringExtra("Path");
ImageView img = (ImageView)findViewById(R.id.photo);
img.setImageURI(Uri.parse(path));
ImageZoomView imageView = new ImageZoomView(
this,getWindow().getWindowManager().getDefaultDisplay().getOrientation());
this.setContentView(imageView);
}
}
它会在屏幕上显示完整的图像，但点击它时，没有任何反应。
答案 0 :(得分：3)
很棒创建一个名为ZoomFunctionality
<强> ZoomFunctionality
package com.androidhive.work;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.ImageView;
public class ZoomFunctionality 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;
// Remember some things for zooming
PointF last = new PointF();
PointF start = new PointF();
float minScale = 1f;
float maxScale = 3f;
float[] m;
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;
public ZoomFunctionality(Context context) {
super(context);
sharedConstructing(context);
}
public ZoomFunctionality(Context context, AttributeSet attrs) {
super(context, attrs);
sharedConstructing(context);
}
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() {
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];
PointF curr = new PointF(event.getX(), event.getY());
switch (event.getAction()) {
case MotionEvent.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)
deltaY = -y;
else if (y + deltaY < -bottom)
deltaY = -(y + bottom);
} else if (scaleHeight < height) {
deltaY = 0;
if (x + deltaX > 0)
deltaX = -x;
else if (x + deltaX < -right)
deltaX = -(x + right);
} else {
if (x + deltaX > 0)
deltaX = -x;
else if (x + deltaX < -right)
deltaX = -(x + right);
if (y + deltaY > 0)
deltaY = -y;
else if (y + deltaY < -bottom)
deltaY = -(y + bottom);
}
matrix.postTranslate(deltaX, deltaY);
last.set(curr.x, curr.y);
}
break;
case MotionEvent.ACTION_UP:
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)
performClick();
break;
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
}
setImageMatrix(matrix);
invalidate();
return true; // indicate event was handled
}
});
}
@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;
}
@Override
public boolean onScale(ScaleGestureDetector detector) {
float mScaleFactor = detector.getScaleFactor();
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);
}
}
现在，当您想要从ZoomFunctionality拨打Activity时，请写下以下声明
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2;
Bitmap bmp = BitmapFactory.decodeFile(filename, options);
ZoomFunctionality img = new ZoomFunctionality(this);
img.setImageBitmap(bmp);
img.setMaxZoom(4f);
setContentView(img);
注意
bmp：您想要缩放功能的位图图像是什么
这个：建议您使用Activity.this
没有必要使用BitmapFactoryOptions，但需要从文件名解码
答案 1 :(得分：1)
TouchImageView.java
package com.animation.sound;
import android.content.Context;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.ImageView;
public class TouchImageView extends ImageView {
Matrix 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 last = new PointF();
PointF start = new PointF();
float minScale = 1f;
float maxScale = 3f;
float[] m;
int viewWidth, viewHeight;
static final int CLICK = 3;
float saveScale = 1f;
protected float origWidth, origHeight;
int oldMeasuredWidth, oldMeasuredHeight;
ScaleGestureDetector mScaleDetector;
Context context;
public TouchImageView(Context context) {
super(context);
sharedConstructing(context);
}
public TouchImageView(Context context, AttributeSet attrs) {
super(context, attrs);
sharedConstructing(context);
}
private void sharedConstructing(Context context) {
super.setClickable(true);
this.context = context;
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
matrix = new Matrix();
m = new float[9];
setImageMatrix(matrix);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
PointF curr = new PointF(event.getX(), event.getY());
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
last.set(curr);
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 fixTransX = getFixDragTrans(deltaX, viewWidth,
origWidth * saveScale);
float fixTransY = getFixDragTrans(deltaY, viewHeight,
origHeight * saveScale);
matrix.postTranslate(fixTransX, fixTransY);
fixTrans();
last.set(curr.x, curr.y);
}
break;
case MotionEvent.ACTION_UP:
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)
performClick();
break;
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
}
setImageMatrix(matrix);
invalidate();
return true; // indicate event was handled
}
});
}
public void setMaxZoom(float x) {
maxScale = x;
}
private class ScaleListener extends
ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
mode = ZOOM;
return true;
}
@Override
public boolean onScale(ScaleGestureDetector detector) {
float mScaleFactor = detector.getScaleFactor();
float origScale = saveScale;
saveScale *= mScaleFactor;
if (saveScale > maxScale) {
saveScale = maxScale;
mScaleFactor = maxScale / origScale;
} else if (saveScale < minScale) {
saveScale = minScale;
mScaleFactor = minScale / origScale;
}
if (origWidth * saveScale <= viewWidth
|| origHeight * saveScale <= viewHeight)
matrix.postScale(mScaleFactor, mScaleFactor, viewWidth / 2,
viewHeight / 2);
else
matrix.postScale(mScaleFactor, mScaleFactor,
detector.getFocusX(), detector.getFocusY());
fixTrans();
return true;
}
}
void fixTrans() {
matrix.getValues(m);
float transX = m[Matrix.MTRANS_X];
float transY = m[Matrix.MTRANS_Y];
float fixTransX = getFixTrans(transX, viewWidth, origWidth * saveScale);
float fixTransY = getFixTrans(transY, viewHeight, origHeight
* saveScale);
if (fixTransX != 0 || fixTransY != 0)
matrix.postTranslate(fixTransX, fixTransY);
}
float getFixTrans(float trans, float viewSize, float contentSize) {
float minTrans, maxTrans;
if (contentSize <= viewSize) {
minTrans = 0;
maxTrans = viewSize - contentSize;
} else {
minTrans = viewSize - contentSize;
maxTrans = 0;
}
if (trans < minTrans)
return -trans + minTrans;
if (trans > maxTrans)
return -trans + maxTrans;
return 0;
}
float getFixDragTrans(float delta, float viewSize, float contentSize) {
if (contentSize <= viewSize) {
return 0;
}
return delta;
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
viewWidth = MeasureSpec.getSize(widthMeasureSpec);
viewHeight = MeasureSpec.getSize(heightMeasureSpec);
//
// Rescales image on rotation
//
if (oldMeasuredHeight == viewWidth && oldMeasuredHeight == viewHeight
|| viewWidth == 0 || viewHeight == 0)
return;
oldMeasuredHeight = viewHeight;
oldMeasuredWidth = viewWidth;
if (saveScale == 1) {
// Fit to screen.
float scale;
Drawable drawable = getDrawable();
if (drawable == null || drawable.getIntrinsicWidth() == 0
|| drawable.getIntrinsicHeight() == 0)
return;
int bmWidth = drawable.getIntrinsicWidth();
int bmHeight = drawable.getIntrinsicHeight();
Log.d("bmSize", "bmWidth: " + bmWidth + " bmHeight : " + bmHeight);
float scaleX = (float) viewWidth / (float) bmWidth;
float scaleY = (float) viewHeight / (float) bmHeight;
scale = Math.min(scaleX, scaleY);
matrix.setScale(scale, scale);
// Center the image
float redundantYSpace = (float) viewHeight
- (scale * (float) bmHeight);
float redundantXSpace = (float) viewWidth
- (scale * (float) bmWidth);
redundantYSpace /= (float) 2;
redundantXSpace /= (float) 2;
matrix.postTranslate(redundantXSpace, redundantYSpace);
origWidth = viewWidth - 2 * redundantXSpace;
origHeight = viewHeight - 2 * redundantYSpace;
setImageMatrix(matrix);
}
fixTrans();
}
}
将这些行放在MainActivity.java类中......
TouchImageView imgView;
imgView = (TouchImageView) findViewById(R.id.imgmstlv);
更多信息。请点击此链接Zoom In & Zoom out