// --参数计算---------------------------------------------------------------
public void resetZoomState(ImageZoomView view, Bitmap bitmap) {
mView = view;
mBitmap = bitmap;
mAspectQuotient = -1;
do {
if (null == mView || null == mBitmap) {
break;
}
if (mView.getHeight() <= 0
|| mView.getWidth() <= 0
|| mBitmap.getHeight() <= 0
|| mBitmap.getWidth() <= 0) {
break;
}
mAspectQuotient =
(((float) mBitmap.getWidth()) / mBitmap.getHeight())
/ (((float) mView.getWidth()) / mView.getHeight());
logd("mAspectQuotient = " + mAspectQuotient);
calculateMinMaxZoom();
calculateMinMaxPanX();
calculateMinMaxPanY();
// 初始化OK，通知外部，显示小图标
setZoomChanged();
notifyObservers();
} while (false);
}
private void calculateMinMaxPanY() {
if (mAspectQuotient > 0) {
float bmpH = mBitmap.getHeight();
float viewH = mView.getHeight();
float zoomY = getZoomY();
mStdMinPanY = viewH / (zoomY * 2 * bmpH);
mStdMaxPanY = 1 - mStdMinPanY;
if (mAspectQuotient > 1) {
if (mZoom <= mMidZoom) { // 上下两边出现空隙时，居中显示
mStdMinPanY = mStdMaxPanY = 0.5f;
}
} else {
if (mZoom <= mStdMinZoom) {
mStdMinPanY = mStdMaxPanY = 0.5f;
}
}
mMinPanY = (viewH / 2 + 10) / (zoomY * 2 * bmpH);
mMaxPanY = 1 - mMinPanY;
logd("mStdMinPanY,mStdMaxPanY =" + mStdMinPanY + "," + mStdMaxPanY);
logd("mMinPanY,mMaxPanY =" + mMinPanY + "," + mMaxPanY);
}
}
private void calculateMinMaxZoom() {
if (mAspectQuotient > 0) {
float bmpW = mBitmap.getWidth();
float viewW = mView.getWidth();
float bmpH = mBitmap.getHeight();
float viewH = mView.getHeight();
if (mAspectQuotient > 1) {
mStdMinZoom = 1;
mMidZoom = mAspectQuotient;
mStdMaxZoom = bmpW / viewW;
} else {
mStdMinZoom = 1;
mMidZoom = 1 / mAspectQuotient;
mStdMaxZoom = bmpH / viewH;
}
mZoom = mStdMinZoom;
mMinZoom = mStdMinZoom * (1 - 0.35f);
mMaxZoom = mStdMaxZoom * (1 + 0.2f);
logd("mStdMinZoom,mStdMaxZoom =" + mStdMinZoom + "," + mStdMaxZoom);
logd("mMinZoom,mMidZoom,mMaxZoom =" + mMinZoom + "," + mMidZoom + "," + mMaxZoom);
}
}
public float getZoomY() {
mZoom = adjustZoom(mZoom);
return Math.min(mZoom, mZoom / mAspectQuotient) * mView.getHeight() / mBitmap.getHeight();
}
