Android 在按矩阵缩放imageview时,如何定义最大和最小缩放lvl
霍伊, 这是我的班级:Android 在按矩阵缩放imageview时,如何定义最大和最小缩放lvl,android,android-imageview,Android,Android Imageview,霍伊, 这是我的班级: public class MultiTouchHandler implements OnTouchListener { private static final int NONE = 0; private static final int DRAG = 1; private static final int ZOOM = 2; private static final float MIN_ZOOM = 0.5f; private static final float MA
public class MultiTouchHandler implements OnTouchListener {
private static final int NONE = 0;
private static final int DRAG = 1;
private static final int ZOOM = 2;
private static final float MIN_ZOOM = 0.5f;
private static final float MAX_ZOOM = 2.0f;
private int mode = NONE;
private float oldDist;
private PointF mid;
private PointF start;
private Matrix matrix;
private Matrix savedMatrix;
private ImageView reticle;
private int imageWidth;
private int imageHeight;
private float[] values;
private boolean isTouched;
private float width;
private float height;
private float scale;
public MultiTouchHandler(ImageView v) {
reticle = v;
v.setOnTouchListener(this);
mid = new PointF();
start = new PointF();
imageWidth = v.getDrawable().getIntrinsicWidth();
imageHeight = v.getDrawable().getIntrinsicHeight();
matrix = new Matrix();
savedMatrix = new Matrix();
values = new float[9];
}
public boolean onTouch(View v, MotionEvent event) {
synchronized (this) {
if(reticle.getScaleType() != ScaleType.MATRIX){
reticle.setScaleType(ScaleType.MATRIX);
matrix.postTranslate(reticle.getWidth()/2 - imageWidth/2, reticle.getHeight()/2 - imageHeight/2);
reticle.setImageMatrix(matrix);
}
matrix.getValues(values);
width = values[0]*imageWidth;
height = values[4]*imageHeight;
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
if(event.getX() > values[2] && event.getX() < values[2] + width &&
event.getY() > values[5] && event.getY() < values[5] + height){
start.set(event.getX(), event.getY());
isTouched = true;
}
mode = DRAG;
break;
case MotionEvent.ACTION_POINTER_DOWN:
oldDist = spacing(event);
if (oldDist > 10f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
isTouched = false;
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG && isTouched) {
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);
}
else if (mode == ZOOM) {
float newDist = spacing(event);
if (newDist > 10f) {
matrix.set(savedMatrix);
scale = newDist / oldDist;
Log.v("scale", "" + scale);
scale = Math.max(MIN_ZOOM, Math.min(scale, MAX_ZOOM));
Log.v("new scale", "" + scale);
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
reticle.setImageMatrix(matrix);
return true;
}
}
private float spacing(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
公共类多点触控处理器实现OnTouchListener{
私有静态final int NONE=0;
专用静态最终整数拖动=1;
私有静态最终整数缩放=2;
专用静态最终浮动最小值(放大倍数=0.5f);
专用静态最终浮点最大缩放=2.0f;
私有int模式=无;
私人浮动区;
私有点f-mid;
专用点启动;
私有矩阵;
私有矩阵存储矩阵;
专用图像视图十字线;
私有整数图像宽度;
私人内部图像高度;
私有浮动[]值;
私有布尔值被触发;
私有浮动宽度;
私人浮动高度;
私人浮动比例;
公共多点触控处理器(ImageView v){
十字线=v;
v、 setOnTouchListener(这个);
mid=新点F();
开始=新的点f();
imageWidth=v.getDrawable().getIntrinsicWidth();
imageHeight=v.getDrawable().getIntrinsicHeight();
矩阵=新矩阵();
savedMatrix=新矩阵();
数值=新的浮动[9];
}
公共布尔onTouch(视图v,运动事件){
已同步(此){
if(十字线.getScaleType()!=ScaleType.MATRIX){
十字线.设置刻度类型(刻度类型.矩阵);
postTranslate(retile.getWidth()/2-imageWidth/2,retile.getHeight()/2-imageHeight/2);
十字线。setImageMatrix(矩阵);
}
矩阵。获取值(值);
宽度=值[0]*imageWidth;
高度=值[4]*图像高度;
开关(event.getAction()&MotionEvent.ACTION\u掩码){
case MotionEvent.ACTION\u DOWN:
savedMatrix.set(矩阵);
if(event.getX()>values[2]&&event.getX()值[5]&&event.getY(){
set(event.getX(),event.getY());
isTouched=true;
}
模式=拖动;
打破
case MotionEvent.ACTION\u指针\u向下:
oldDist=间距(事件);
如果(旧区>10f){
savedMatrix.set(矩阵);
中点(中点,事件);
模式=缩放;
}
打破
case MotionEvent.ACTION\u UP:
case MotionEvent.ACTION\u指针\u向上:
模式=无;
isTouched=false;
打破
case MotionEvent.ACTION\u移动:
如果(模式==拖动并触摸(&I){
矩阵集(savedMatrix);
postTranslate(event.getX()-start.x,event.getY()-start.y);
}
else if(模式==缩放){
float newDist=间距(事件);
如果(新距离>10f){
矩阵集(savedMatrix);
比例=新距离/旧距离;
对数v(“刻度”,“刻度+刻度”);
scale=Math.max(最小缩放,数学最小(缩放,最大缩放));
对数v(“新标度”、“标度+标度”);
矩阵。后标度(标度、标度、中x、中y);
}
}
打破
}
十字线。setImageMatrix(矩阵);
返回true;
}
}
专用浮动间距(MotionEvent事件){
float x=event.getX(0)-event.getX(1);
float y=event.getY(0)-event.getY(1);
返回FloatMath.sqrt(x*x+y*y);
}
专用空心中点(点F点、MotionEvent事件){
float x=event.getX(0)+event.getX(1);
float y=event.getY(0)+event.getY(1);
点集(x/2,y/2);
}
}
问题是,它只适用于实际的收缩/缩放,而不适用于全局缩放。。。我试图保存全局比例,每次我缩放时,我将实际比例乘以全局比例,但这是有用的。。。从矩阵中得到的比例a是全局的,但它的行为不像一。我做错了什么?有人能帮忙吗?谢谢你的回答。我就是这样解决的。。。它不是很优雅,但很管用
else if (mode == ZOOM) {
float newDist = spacing(event);
if (newDist > 10f) {
matrix.set(savedMatrix);
matrix.getValues(values);
if(values[0] < MAX_ZOOM && values[0] > MIN_ZOOM){
scale = newDist / oldDist;
scale = Math.max(MIN_ZOOM, Math.min(scale, MAX_ZOOM));
matrix.postScale(scale, scale, mid.x, mid.y);
reticle.setImageMatrix(matrix);
} else if(values[0] >= MAX_ZOOM){
newScale = newDist / oldDist;
if(newScale < scale){
scale = newScale;
scale = Math.max(MIN_ZOOM, Math.min(scale, MAX_ZOOM));
matrix.postScale(scale, scale, mid.x, mid.y);
reticle.setImageMatrix(matrix);
}
} else if(values[0] <= MIN_ZOOM){
newScale = newDist / oldDist;
if(newScale > scale){
scale = newScale;
scale = Math.max(MIN_ZOOM, Math.min(scale, MAX_ZOOM));
matrix.postScale(scale, scale, mid.x, mid.y);
reticle.setImageMatrix(matrix);
}
}
}
}
else if(模式==缩放){
float newDist=间距(事件);
如果(新距离>10f){
矩阵集(savedMatrix);
矩阵。获取值(值);
if(值[0]MIN\u缩放){
比例=新距离/旧距离;
scale=Math.max(最小缩放,数学最小(缩放,最大缩放));
矩阵。后标度(标度、标度、中x、中y);
十字线。setImageMatrix(矩阵);
}else if(值[0]>=最大缩放){
newScale=newDist/oldDist;
if(新闻规模<规模){
规模=新闻规模;
scale=Math.max(最小缩放,数学最小(缩放,最大缩放));
矩阵。后标度(标度、标度、中x、中y);
十字线。setImageMatrix(矩阵);
}
}else if(值[0]比例){
规模=新闻规模;
scale=Math.max(最小缩放,数学最小(缩放,最大缩放));
矩阵。后标度(标度、标度、中x、中y);
十字线。setImageMatrix(矩阵);
}
}
}
}
这是我编辑的代码中唯一的和平为什么没有人使用
scalegestruedetector
?我正在做一些非常类似的工作,并使用一个扩展了ScaleGestureDetector.SimpleOnScaleListener
的小助手类
class ScaleListener extends
ScaleGestureDetector.SimpleOnScaleGestureListener {
float scaleFactor;
Matrix matrix;
public ScaleListener(){
super();
scaleFactor = 1.0f;
matrix = new Matrix();
}
public boolean onScale(ScaleGestureDetector detector){
//updating the scalefactor after the current gesture
scaleFactor *= detector.getScaleFactor();
//making sure the scale is within the limits
scaleFactor = Math.max(MIN_ZOOM, Math.min(scaleFactor, MAX_ZOOM));
//applying the scale via a matrix to the imageview
matrix.setScale(scaleFactor, scaleFactor);
imageview.setImageMatrix(matrix)
}
}
您关于全局比例的问题让我有点困惑,但是矩阵/比例因子包含imageview的全局比例。希望这有帮助,尽管这是一个