Android用两个手指缩放-onTouch和setScaleX,setScaleY
保加利亚的问候:) 我正在解决一个关于使用setScaleX和setScaleY缩放的Android编程作业。问题是在我缩放并移除手指后出现的。所以我移除手指并再次将它们放在屏幕上,然后ImageView重新缩放。我不想那样Android用两个手指缩放-onTouch和setScaleX,setScaleY,android,zooming,Android,Zooming,保加利亚的问候:) 我正在解决一个关于使用setScaleX和setScaleY缩放的Android编程作业。问题是在我缩放并移除手指后出现的。所以我移除手指并再次将它们放在屏幕上,然后ImageView重新缩放。我不想那样 @Override public boolean onTouch(View v, MotionEvent event) { if (event.getPointerCount() == 1) { }
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getPointerCount() == 1) {
} else if (event.getPointerCount() == 2) {
if (event.getActionMasked() == MotionEvent.ACTION_POINTER_DOWN
|| event.getActionMasked() == MotionEvent.ACTION_DOWN) {
float diff_y = event.getY(0) - event.getY(1);
float diff_x = event.getX(0) - event.getX(1);
history_angle = (float) Math.toDegrees(Math.atan2(
diff_y, diff_x));
history_dist = FloatMath.sqrt(diff_x * diff_x
+ diff_y * diff_y);
} else if (event.getActionMasked() == MotionEvent.ACTION_MOVE) {
float diff_y = event.getY(0) - event.getY(1);
float diff_x = event.getX(0) - event.getX(1);
float angle = (float) Math.toDegrees(Math.atan2(diff_y,
diff_x));
float dist_angle = angle - history_angle;
img.setRotation(img.getRotation() + dist_angle);
history_angle = angle;
float distCurrent = FloatMath.sqrt(diff_x * diff_x
+ diff_y * diff_y);
float curScale = distCurrent / history_dist;
img.setScaleX(curScale);
img.setScaleY(curScale);
}
}
return true;
}
});
请告知
提前感谢您的帮助,祝您愉快:)
注意:在作业中,我必须使用setScaleX和setScaleY以及手指之间的距离:)你应该使用矩阵 这里是代码,我希望下面的序列将帮助您:
public class TouchImageView extends ImageView {
private static final String TAG = "Touch";
// These matrices will be used to move and zoom image
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 mid = new PointF();
float oldDist = 1f;
Context context;
public TouchImageView(Context context) {
super(context);
super.setClickable(true);
this.context = context;
matrix.setTranslate(1f, 1f);
setImageMatrix(matrix);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent rawEvent) {
WrapMotionEvent event = WrapMotionEvent.wrap(rawEvent);
// Dump touch event to log
if (Viewer.isDebug == true){
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");
}
break;
case MotionEvent.ACTION_UP:
int xDiff = (int) Math.abs(event.getX() - start.x);
int yDiff = (int) Math.abs(event.getY() - start.y);
if (xDiff < 8 && yDiff < 8){
performClick();
}
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
Log.d(TAG, "mode=NONE");
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
// ...
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, 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;
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
setImageMatrix(matrix);
return true; // indicate event was handled
}
});
}
public void setImage(Bitmap bm, int displayWidth, int displayHeight) {
super.setImageBitmap(bm);
//Fit to screen.
float scale;
if ((displayHeight / bm.getHeight()) >= (displayWidth / bm.getWidth())){
scale = (float)displayWidth / (float)bm.getWidth();
} else {
scale = (float)displayHeight / (float)bm.getHeight();
}
savedMatrix.set(matrix);
matrix.set(savedMatrix);
matrix.postScale(scale, scale, mid.x, mid.y);
setImageMatrix(matrix);
// Center the image
float redundantYSpace = (float)displayHeight - (scale * (float)bm.getHeight()) ;
float redundantXSpace = (float)displayWidth - (scale * (float)bm.getWidth());
redundantYSpace /= (float)2;
redundantXSpace /= (float)2;
savedMatrix.set(matrix);
matrix.set(savedMatrix);
matrix.postTranslate(redundantXSpace, redundantYSpace);
setImageMatrix(matrix);
}
/** 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);
}
}
公共类TouchImageView扩展了ImageView{
私有静态最终字符串TAG=“Touch”;
//这些矩阵将用于移动和缩放图像
矩阵=新矩阵();
矩阵savedMatrix=新矩阵();
//我们可能处于这三种状态之一
静态最终int NONE=0;
静态最终整数阻力=1;
静态最终整数缩放=2;
int模式=无;
//记住一些关于缩放的事情
PointF start=新的PointF();
PointF mid=新的PointF();
浮动oldDist=1f;
语境;
公共TouchImageView(上下文){
超级(上下文);
super.setClickable(true);
this.context=上下文;
矩阵.setTranslate(1f,1f);
setImageMatrix(矩阵);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(新的OnTouchListener(){
@凌驾
公共布尔onTouch(视图v、MotionEvent和rawEvent){
WrapMotionEvent=WrapMotionEvent.wrap(rawEvent);
//将触摸事件转储到日志
如果(Viewer.isDebug==true){
dumpEvent(事件);
}
//在这里处理触摸事件。。。
开关(event.getAction()&MotionEvent.ACTION\u掩码){
case MotionEvent.ACTION\u DOWN:
savedMatrix.set(矩阵);
set(event.getX(),event.getY());
Log.d(标记“mode=DRAG”);
模式=拖动;
打破
case MotionEvent.ACTION\u指针\u向下:
oldDist=间距(事件);
Log.d(标记“oldDist=“+oldDist”);
如果(旧区>10f){
savedMatrix.set(矩阵);
中点(中点,事件);
模式=缩放;
Log.d(标记“mode=ZOOM”);
}
打破
case MotionEvent.ACTION\u UP:
intxdiff=(int)Math.abs(event.getX()-start.x);
int-yDiff=(int)Math.abs(event.getY()-start.y);
if(xDiff<8&&yDiff<8){
performClick();
}
case MotionEvent.ACTION\u指针\u向上:
模式=无;
Log.d(标记“mode=NONE”);
打破
case MotionEvent.ACTION\u移动:
如果(模式==拖动){
// ...
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);
Log.d(标记“newDist=“+newDist”);
如果(新距离>10f){
矩阵集(savedMatrix);
浮动比例=新距离/旧距离;
矩阵。后标度(标度、标度、中x、中y);
}
}
打破
}
setImageMatrix(矩阵);
返回true;//指示事件已处理
}
});
}
public void setImage(位图bm、int displayWidth、int displayHeight){
super.setImageBitmap(bm);
//适合屏幕。
浮标;
如果((displayHeight/bm.getHeight())>=(displayWidth/bm.getWidth()){
scale=(float)displayWidth/(float)bm.getWidth();
}否则{
scale=(float)displayHeight/(float)bm.getHeight();
}
savedMatrix.set(矩阵);
矩阵集(savedMatrix);
矩阵。后标度(标度、标度、中x、中y);
setImageMatrix(矩阵);
//将图像居中
float redundantYSpace=(float)displayHeight-(scale*(float)bm.getHeight());
float redundantXSpace=(float)displayWidth-(scale*(float)bm.getWidth());
redundantYSpace/=(float)2;
redundantXSpace/=(float)2;
savedMatrix.set(矩阵);
矩阵集(savedMatrix);
postTranslate(redundantXSpace,redundantYSpace);
setImageMatrix(矩阵);
}
/**在LogCat视图中显示事件以进行调试*/
私有void dumpEvent(WrapMotionEvent事件){
// ...
字符串名称[]={“向下”、“向上”、“移动”、“取消”、“外部”,
“指针向下”、“指针向上”、“7?”、“8?”、“9?”;
StringBuilder sb=新的StringBuilder();
int action=event.getAction();
int actionCode=action&MotionEvent.action\u掩码;
附加(名称[动作代码]);
如果(actionCode==MotionEvent.ACTION\u指针\u向下
||actionCode==MotionEvent.ACTION(指针向上){
某人追加(“(pid”)。追加(
动作>>MotionEvent.action\u指针\u ID\u移位);
某人加上(“)”;
}
某人加上(“[”);
for(int i=0;i