我正在使用Chris Bane的
PhotoView在ViewPager中显示ImageViews.我想在用户放大图像时禁用ViewPager的滚动.我已经找到了这个
Hacky ViewPager,可以通过调用toggleLock()来启用/禁用滚动.
public class HackyViewPager extends ViewPager {
private boolean isLocked;
public HackyViewPager(Context context) {
super(context);
isLocked = false;
}
public HackyViewPager(Context context,AttributeSet attrs) {
super(context,attrs);
isLocked = false;
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
if (!isLocked) {
try {
return super.onInterceptTouchEvent(ev);
}
catch (IllegalArgumentException e) {
e.printStackTrace();
return false;
}
}
return false;
}
@Override
public boolean onTouchEvent(MotionEvent event) {
return !isLocked && super.onTouchEvent(event);
}
public void toggleLock() {
isLocked = !isLocked;
}
public void setLocked(boolean isLocked) {
this.isLocked = isLocked;
}
public boolean isLocked() {
return isLocked;
}
}
所以我的问题是,我不确定我必须在哪个位置调用toogleLock().我想我必须实现一个监听器,但我不确定哪一个是最好的.在此先感谢帮助我！
编辑：我自己想出来了！
photoview.setOnMatrixChangeListener(new PhotoViewAttacher.OnMatrixChangedListener() {
@Override
public void onMatrixChanged(RectF rectF) {
if (photoview.getScale() > 1) {
sPager.setLocked(true);
} else {
sPager.setLocked(false);
}
}
});
解决方法
对我来说,photoview.getScale()== 1总是和我一起使用缩放.
setOnScaleChangeListener中的scaleFactor只是某个时间的刻度,与前一个值无关.我们需要计算累积scaleFactor.
private float cumulScaleFactor = 1;
photoViewAttacher.setOnScaleChangeListener(new PhotoViewAttacher.OnScaleChangeListener() {
@Override
public void onScaleChange(final float scaleFactor,final float focusX,final float focusY) {
cumulScaleFactor = cumulScaleFactor * scaleFactor;
sPager.setLocked(isValueApproximate(1.0f,cumulScaleFactor));
}
});
private boolean isValueApproximate(final float expectedValue,final float value) {
final float errorMargin = 0.01f;
return Math.abs(expectedValue - value) < errorMargin;
}
