ImageView ScaleType
public class ImageView {
private void configureBounds() {
if (mDrawable == null || !mHaveFrame) {
return;
}
int dwidth = mDrawableWidth;
int dheight = mDrawableHeight;
int vwidth = getWidth() - mPaddingLeft - mPaddingRight;
int vheight = getHeight() - mPaddingTop - mPaddingBottom;
boolean fits = (dwidth < 0 || vwidth == dwidth) &&
(dheight < 0 || vheight == dheight);
if (dwidth <= 0 || dheight <= 0 || ScaleType.FIT_XY == mScaleType) {
/* If the drawable has no intrinsic size, or we're told to
scaletofit, then we just fill our entire view.
*/
mDrawable.setBounds(0, 0, vwidth, vheight);
mDrawMatrix = null;
} else {
// We need to do the scaling ourself, so have the drawable
// use its native size.
mDrawable.setBounds(0, 0, dwidth, dheight);
if (ScaleType.MATRIX == mScaleType) {
// Use the specified matrix as-is.
if (mMatrix.isIdentity()) {
mDrawMatrix = null;
} else {
mDrawMatrix = mMatrix;
}
} else if (fits) {
// The bitmap fits exactly, no transform needed.
mDrawMatrix = null;
} else if (ScaleType.CENTER == mScaleType) {
// Center bitmap in view, no scaling.
mDrawMatrix = mMatrix;
mDrawMatrix.setTranslate((int) ((vwidth - dwidth) * 0.5f + 0.5f),
(int) ((vheight - dheight) * 0.5f + 0.5f));
} else if (ScaleType.CENTER_CROP == mScaleType) {
mDrawMatrix = mMatrix;
float scale;
float dx = 0, dy = 0;
if (dwidth * vheight > vwidth * dheight) {
scale = (float) vheight / (float) dheight;
dx = (vwidth - dwidth * scale) * 0.5f;
} else {
scale = (float) vwidth / (float) dwidth;
dy = (vheight - dheight * scale) * 0.5f;
}
mDrawMatrix.setScale(scale, scale);
mDrawMatrix.postTranslate((int) (dx + 0.5f), (int) (dy + 0.5f));
} else if (ScaleType.CENTER_INSIDE == mScaleType) {
mDrawMatrix = mMatrix;
float scale;
float dx;
float dy;
if (dwidth <= vwidth && dheight <= vheight) {
scale = 1.0f;
} else {
scale = Math.min((float) vwidth / (float) dwidth,
(float) vheight / (float) dheight);
}
dx = (int) ((vwidth - dwidth * scale) * 0.5f + 0.5f);
dy = (int) ((vheight - dheight * scale) * 0.5f + 0.5f);
mDrawMatrix.setScale(scale, scale);
mDrawMatrix.postTranslate(dx, dy);
} else {
// Generate the required transform.
mTempSrc.set(0, 0, dwidth, dheight);
mTempDst.set(0, 0, vwidth, vheight);
mDrawMatrix = mMatrix;
mDrawMatrix.setRectToRect(mTempSrc, mTempDst, scaleTypeToScaleToFit(mScaleType));
}
}
}
}