* Note that this view could be still smaller than 100 x 100 using this approach if the original * image is small. To set an image to a fixed size, specify that size in the layout params and * then use {@link #setScaleType(android.widget.ImageView.ScaleType)} to determine how to fit * the image within the bounds. *
* * @param maxWidth maximum width for this view * * @see #getMaxWidth() * * @attr ref android.R.styleable#ImageView_maxWidth */ @android.view.RemotableViewMethod public void setMaxWidth(int maxWidth) { mMaxWidth = maxWidth; } /** * The maximum height of this view. * * @return The maximum height of this view * * @see #setMaxHeight(int) * * @attr ref android.R.styleable#ImageView_maxHeight */ public int getMaxHeight() { return mMaxHeight; } /** * An optional argument to supply a maximum height for this view. Only valid if * {@link #setAdjustViewBounds(boolean)} has been set to true. To set an image to be a * maximum of 100 x 100 while preserving the original aspect ratio, do the following: 1) set * adjustViewBounds to true 2) set maxWidth and maxHeight to 100 3) set the height and width * layout params to WRAP_CONTENT. * ** Note that this view could be still smaller than 100 x 100 using this approach if the original * image is small. To set an image to a fixed size, specify that size in the layout params and * then use {@link #setScaleType(android.widget.ImageView.ScaleType)} to determine how to fit * the image within the bounds. *
* * @param maxHeight maximum height for this view * * @see #getMaxHeight() * * @attr ref android.R.styleable#ImageView_maxHeight */ @android.view.RemotableViewMethod public void setMaxHeight(int maxHeight) { mMaxHeight = maxHeight; } /** Return the view's drawable, or null if no drawable has been assigned. */ public Drawable getDrawable() { return mDrawable; } /** * Sets a drawable as the content of this ImageView. * *This does Bitmap reading and decoding on the UI * thread, which can cause a latency hiccup. If that's a concern, * consider using {@link #setImageDrawable(android.graphics.drawable.Drawable)} or * {@link #setImageBitmap(android.graphics.Bitmap)} and * {@link android.graphics.BitmapFactory} instead.
* * @param resId the resource identifier of the the drawable * * @attr ref android.R.styleable#ImageView_src */ @android.view.RemotableViewMethod public void setImageResource(int resId) { if (mUri != null || mResource != resId) { updateDrawable(null); mResource = resId; mUri = null; final int oldWidth = mDrawableWidth; final int oldHeight = mDrawableHeight; resolveUri(); if (oldWidth != mDrawableWidth || oldHeight != mDrawableHeight) { requestLayout(); } invalidate(); } } /** * Sets the content of this ImageView to the specified Uri. * *This does Bitmap reading and decoding on the UI * thread, which can cause a latency hiccup. If that's a concern, * consider using {@link #setImageDrawable(android.graphics.drawable.Drawable)} or * {@link #setImageBitmap(android.graphics.Bitmap)} and * {@link android.graphics.BitmapFactory} instead.
* * @param uri The Uri of an image */ @android.view.RemotableViewMethod public void setImageURI(Uri uri) { if (mResource != 0 || (mUri != uri && (uri == null || mUri == null || !uri.equals(mUri)))) { updateDrawable(null); mResource = 0; mUri = uri; final int oldWidth = mDrawableWidth; final int oldHeight = mDrawableHeight; resolveUri(); if (oldWidth != mDrawableWidth || oldHeight != mDrawableHeight) { requestLayout(); } invalidate(); } } /** * Sets a drawable as the content of this ImageView. * * @param drawable The drawable to set */ public void setImageDrawable(Drawable drawable) { if (mDrawable != drawable) { mResource = 0; mUri = null; final int oldWidth = mDrawableWidth; final int oldHeight = mDrawableHeight; updateDrawable(drawable); if (oldWidth != mDrawableWidth || oldHeight != mDrawableHeight) { requestLayout(); } invalidate(); } } /** * Sets a Bitmap as the content of this ImageView. * * @param bm The bitmap to set */ @android.view.RemotableViewMethod public void setImageBitmap(Bitmap bm) { // if this is used frequently, may handle bitmaps explicitly // to reduce the intermediate drawable object setImageDrawable(new BitmapDrawable(mContext.getResources(), bm)); } public void setImageState(int[] state, boolean merge) { mState = state; mMergeState = merge; if (mDrawable != null) { refreshDrawableState(); resizeFromDrawable(); } } @Override public void setSelected(boolean selected) { super.setSelected(selected); resizeFromDrawable(); } /** * Sets the image level, when it is constructed from a * {@link android.graphics.drawable.LevelListDrawable}. * * @param level The new level for the image. */ @android.view.RemotableViewMethod public void setImageLevel(int level) { mLevel = level; if (mDrawable != null) { mDrawable.setLevel(level); resizeFromDrawable(); } } /** * Options for scaling the bounds of an image to the bounds of this view. */ public enum ScaleType { /** * Scale using the image matrix when drawing. The image matrix can be set using * {@link ImageView#setImageMatrix(Matrix)}. From XML, use this syntax: *android:scaleType="matrix".
*/
MATRIX (0),
/**
* Scale the image using {@link Matrix.ScaleToFit#FILL}.
* From XML, use this syntax: android:scaleType="fitXY".
*/
FIT_XY (1),
/**
* Scale the image using {@link Matrix.ScaleToFit#START}.
* From XML, use this syntax: android:scaleType="fitStart".
*/
FIT_START (2),
/**
* Scale the image using {@link Matrix.ScaleToFit#CENTER}.
* From XML, use this syntax:
* android:scaleType="fitCenter".
*/
FIT_CENTER (3),
/**
* Scale the image using {@link Matrix.ScaleToFit#END}.
* From XML, use this syntax: android:scaleType="fitEnd".
*/
FIT_END (4),
/**
* Center the image in the view, but perform no scaling.
* From XML, use this syntax: android:scaleType="center".
*/
CENTER (5),
/**
* Scale the image uniformly (maintain the image's aspect ratio) so
* that both dimensions (width and height) of the image will be equal
* to or larger than the corresponding dimension of the view
* (minus padding). The image is then centered in the view.
* From XML, use this syntax: android:scaleType="centerCrop".
*/
CENTER_CROP (6),
/**
* Scale the image uniformly (maintain the image's aspect ratio) so
* that both dimensions (width and height) of the image will be equal
* to or less than the corresponding dimension of the view
* (minus padding). The image is then centered in the view.
* From XML, use this syntax: android:scaleType="centerInside".
*/
CENTER_INSIDE (7);
ScaleType(int ni) {
nativeInt = ni;
}
final int nativeInt;
}
/**
* Controls how the image should be resized or moved to match the size
* of this ImageView.
*
* @param scaleType The desired scaling mode.
*
* @attr ref android.R.styleable#ImageView_scaleType
*/
public void setScaleType(ScaleType scaleType) {
if (scaleType == null) {
throw new NullPointerException();
}
if (mScaleType != scaleType) {
mScaleType = scaleType;
setWillNotCacheDrawing(mScaleType == ScaleType.CENTER);
requestLayout();
invalidate();
}
}
/**
* Return the current scale type in use by this ImageView.
*
* @see ImageView.ScaleType
*
* @attr ref android.R.styleable#ImageView_scaleType
*/
public ScaleType getScaleType() {
return mScaleType;
}
/** Return the view's optional matrix. This is applied to the
view's drawable when it is drawn. If there is not matrix,
this method will return null.
Do not change this matrix in place. If you want a different matrix
applied to the drawable, be sure to call setImageMatrix().
*/
public Matrix getImageMatrix() {
return mMatrix;
}
public void setImageMatrix(Matrix matrix) {
// collaps null and identity to just null
if (matrix != null && matrix.isIdentity()) {
matrix = null;
}
// don't invalidate unless we're actually changing our matrix
if (matrix == null && !mMatrix.isIdentity() ||
matrix != null && !mMatrix.equals(matrix)) {
mMatrix.set(matrix);
configureBounds();
invalidate();
}
}
/**
* Return whether this ImageView crops to padding.
*
* @return whether this ImageView crops to padding
*
* @see #setCropToPadding(boolean)
*
* @attr ref android.R.styleable#ImageView_cropToPadding
*/
public boolean getCropToPadding() {
return mCropToPadding;
}
/**
* Sets whether this ImageView will crop to padding.
*
* @param cropToPadding whether this ImageView will crop to padding
*
* @see #getCropToPadding()
*
* @attr ref android.R.styleable#ImageView_cropToPadding
*/
public void setCropToPadding(boolean cropToPadding) {
if (mCropToPadding != cropToPadding) {
mCropToPadding = cropToPadding;
requestLayout();
invalidate();
}
}
private void resolveUri() {
if (mDrawable != null) {
return;
}
Resources rsrc = getResources();
if (rsrc == null) {
return;
}
Drawable d = null;
if (mResource != 0) {
try {
d = rsrc.getDrawable(mResource);
} catch (Exception e) {
Log.w("ImageView", "Unable to find resource: " + mResource, e);
// Don't try again.
mUri = null;
}
} else if (mUri != null) {
String scheme = mUri.getScheme();
if (ContentResolver.SCHEME_ANDROID_RESOURCE.equals(scheme)) {
try {
// Load drawable through Resources, to get the source density information
ContentResolver.OpenResourceIdResult r =
mContext.getContentResolver().getResourceId(mUri);
d = r.r.getDrawable(r.id);
} catch (Exception e) {
Log.w("ImageView", "Unable to open content: " + mUri, e);
}
} else if (ContentResolver.SCHEME_CONTENT.equals(scheme)
|| ContentResolver.SCHEME_FILE.equals(scheme)) {
try {
d = Drawable.createFromStream(
mContext.getContentResolver().openInputStream(mUri),
null);
} catch (Exception e) {
Log.w("ImageView", "Unable to open content: " + mUri, e);
}
} else {
d = Drawable.createFromPath(mUri.toString());
}
if (d == null) {
System.out.println("resolveUri failed on bad bitmap uri: "
+ mUri);
// Don't try again.
mUri = null;
}
} else {
return;
}
updateDrawable(d);
}
@Override
public int[] onCreateDrawableState(int extraSpace) {
if (mState == null) {
return super.onCreateDrawableState(extraSpace);
} else if (!mMergeState) {
return mState;
} else {
return mergeDrawableStates(
super.onCreateDrawableState(extraSpace + mState.length), mState);
}
}
private void updateDrawable(Drawable d) {
if (mDrawable != null) {
mDrawable.setCallback(null);
unscheduleDrawable(mDrawable);
}
mDrawable = d;
if (d != null) {
d.setCallback(this);
if (d.isStateful()) {
d.setState(getDrawableState());
}
d.setLevel(mLevel);
d.setLayoutDirection(getLayoutDirection());
mDrawableWidth = d.getIntrinsicWidth();
mDrawableHeight = d.getIntrinsicHeight();
applyColorMod();
configureBounds();
} else {
mDrawableWidth = mDrawableHeight = -1;
}
}
private void resizeFromDrawable() {
Drawable d = mDrawable;
if (d != null) {
int w = d.getIntrinsicWidth();
if (w < 0) w = mDrawableWidth;
int h = d.getIntrinsicHeight();
if (h < 0) h = mDrawableHeight;
if (w != mDrawableWidth || h != mDrawableHeight) {
mDrawableWidth = w;
mDrawableHeight = h;
requestLayout();
}
}
}
private static final Matrix.ScaleToFit[] sS2FArray = {
Matrix.ScaleToFit.FILL,
Matrix.ScaleToFit.START,
Matrix.ScaleToFit.CENTER,
Matrix.ScaleToFit.END
};
private static Matrix.ScaleToFit scaleTypeToScaleToFit(ScaleType st) {
// ScaleToFit enum to their corresponding Matrix.ScaleToFit values
return sS2FArray[st.nativeInt - 1];
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
resolveUri();
int w;
int h;
// Desired aspect ratio of the view's contents (not including padding)
float desiredAspect = 0.0f;
// We are allowed to change the view's width
boolean resizeWidth = false;
// We are allowed to change the view's height
boolean resizeHeight = false;
final int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
final int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
if (mDrawable == null) {
// If no drawable, its intrinsic size is 0.
mDrawableWidth = -1;
mDrawableHeight = -1;
w = h = 0;
} else {
w = mDrawableWidth;
h = mDrawableHeight;
if (w <= 0) w = 1;
if (h <= 0) h = 1;
// We are supposed to adjust view bounds to match the aspect
// ratio of our drawable. See if that is possible.
if (mAdjustViewBounds) {
resizeWidth = widthSpecMode != MeasureSpec.EXACTLY;
resizeHeight = heightSpecMode != MeasureSpec.EXACTLY;
desiredAspect = (float) w / (float) h;
}
}
int pleft = mPaddingLeft;
int pright = mPaddingRight;
int ptop = mPaddingTop;
int pbottom = mPaddingBottom;
int widthSize;
int heightSize;
if (resizeWidth || resizeHeight) {
/* If we get here, it means we want to resize to match the
drawables aspect ratio, and we have the freedom to change at
least one dimension.
*/
// Get the max possible width given our constraints
widthSize = resolveAdjustedSize(w + pleft + pright, mMaxWidth, widthMeasureSpec);
// Get the max possible height given our constraints
heightSize = resolveAdjustedSize(h + ptop + pbottom, mMaxHeight, heightMeasureSpec);
if (desiredAspect != 0.0f) {
// See what our actual aspect ratio is
float actualAspect = (float)(widthSize - pleft - pright) /
(heightSize - ptop - pbottom);
if (Math.abs(actualAspect - desiredAspect) > 0.0000001) {
boolean done = false;
// Try adjusting width to be proportional to height
if (resizeWidth) {
int newWidth = (int)(desiredAspect * (heightSize - ptop - pbottom)) +
pleft + pright;
if (newWidth <= widthSize) {
widthSize = newWidth;
done = true;
}
}
// Try adjusting height to be proportional to width
if (!done && resizeHeight) {
int newHeight = (int)((widthSize - pleft - pright) / desiredAspect) +
ptop + pbottom;
if (newHeight <= heightSize) {
heightSize = newHeight;
}
}
}
}
} else {
/* We are either don't want to preserve the drawables aspect ratio,
or we are not allowed to change view dimensions. Just measure in
the normal way.
*/
w += pleft + pright;
h += ptop + pbottom;
w = Math.max(w, getSuggestedMinimumWidth());
h = Math.max(h, getSuggestedMinimumHeight());
widthSize = resolveSizeAndState(w, widthMeasureSpec, 0);
heightSize = resolveSizeAndState(h, heightMeasureSpec, 0);
}
setMeasuredDimension(widthSize, heightSize);
}
private int resolveAdjustedSize(int desiredSize, int maxSize,
int measureSpec) {
int result = desiredSize;
int specMode = MeasureSpec.getMode(measureSpec);
int specSize = MeasureSpec.getSize(measureSpec);
switch (specMode) {
case MeasureSpec.UNSPECIFIED:
/* Parent says we can be as big as we want. Just don't be larger
than max size imposed on ourselves.
*/
result = Math.min(desiredSize, maxSize);
break;
case MeasureSpec.AT_MOST:
// Parent says we can be as big as we want, up to specSize.
// Don't be larger than specSize, and don't be larger than
// the max size imposed on ourselves.
result = Math.min(Math.min(desiredSize, specSize), maxSize);
break;
case MeasureSpec.EXACTLY:
// No choice. Do what we are told.
result = specSize;
break;
}
return result;
}
@Override
protected boolean setFrame(int l, int t, int r, int b) {
boolean changed = super.setFrame(l, t, r, b);
mHaveFrame = true;
configureBounds();
return changed;
}
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));
}
}
}
@Override
protected void drawableStateChanged() {
super.drawableStateChanged();
Drawable d = mDrawable;
if (d != null && d.isStateful()) {
d.setState(getDrawableState());
}
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (mDrawable == null) {
return; // couldn't resolve the URI
}
if (mDrawableWidth == 0 || mDrawableHeight == 0) {
return; // nothing to draw (empty bounds)
}
if (mDrawMatrix == null && mPaddingTop == 0 && mPaddingLeft == 0) {
mDrawable.draw(canvas);
} else {
int saveCount = canvas.getSaveCount();
canvas.save();
if (mCropToPadding) {
final int scrollX = mScrollX;
final int scrollY = mScrollY;
canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop,
scrollX + mRight - mLeft - mPaddingRight,
scrollY + mBottom - mTop - mPaddingBottom);
}
canvas.translate(mPaddingLeft, mPaddingTop);
if (mDrawMatrix != null) {
canvas.concat(mDrawMatrix);
}
mDrawable.draw(canvas);
canvas.restoreToCount(saveCount);
}
}
/**
* Return the offset of the widget's text baseline from the widget's top * boundary.
* * @return the offset of the baseline within the widget's bounds or -1 * if baseline alignment is not supported. */ @Override @ViewDebug.ExportedProperty(category = "layout") public int getBaseline() { if (mBaselineAlignBottom) { return getMeasuredHeight(); } else { return mBaseline; } } /** *Set the offset of the widget's text baseline from the widget's top * boundary. This value is overridden by the {@link #setBaselineAlignBottom(boolean)} * property.
* * @param baseline The baseline to use, or -1 if none is to be provided. * * @see #setBaseline(int) * @attr ref android.R.styleable#ImageView_baseline */ public void setBaseline(int baseline) { if (mBaseline != baseline) { mBaseline = baseline; requestLayout(); } } /** * Set whether to set the baseline of this view to the bottom of the view. * Setting this value overrides any calls to setBaseline. * * @param aligned If true, the image view will be baseline aligned with * based on its bottom edge. * * @attr ref android.R.styleable#ImageView_baselineAlignBottom */ public void setBaselineAlignBottom(boolean aligned) { if (mBaselineAlignBottom != aligned) { mBaselineAlignBottom = aligned; requestLayout(); } } /** * Return whether this view's baseline will be considered the bottom of the view. * * @see #setBaselineAlignBottom(boolean) */ public boolean getBaselineAlignBottom() { return mBaselineAlignBottom; } /** * Set a tinting option for the image. * * @param color Color tint to apply. * @param mode How to apply the color. The standard mode is * {@link PorterDuff.Mode#SRC_ATOP} * * @attr ref android.R.styleable#ImageView_tint */ public final void setColorFilter(int color, PorterDuff.Mode mode) { setColorFilter(new PorterDuffColorFilter(color, mode)); } /** * Set a tinting option for the image. Assumes * {@link PorterDuff.Mode#SRC_ATOP} blending mode. * * @param color Color tint to apply. * @attr ref android.R.styleable#ImageView_tint */ @RemotableViewMethod public final void setColorFilter(int color) { setColorFilter(color, PorterDuff.Mode.SRC_ATOP); } public final void clearColorFilter() { setColorFilter(null); } /** * Returns the active color filter for this ImageView. * * @return the active color filter for this ImageView * * @see #setColorFilter(android.graphics.ColorFilter) */ public ColorFilter getColorFilter() { return mColorFilter; } /** * Apply an arbitrary colorfilter to the image. * * @param cf the colorfilter to apply (may be null) * * @see #getColorFilter() */ public void setColorFilter(ColorFilter cf) { if (mColorFilter != cf) { mColorFilter = cf; mColorMod = true; applyColorMod(); invalidate(); } } /** * Returns the alpha that will be applied to the drawable of this ImageView. * * @return the alpha that will be applied to the drawable of this ImageView * * @see #setImageAlpha(int) */ public int getImageAlpha() { return mAlpha; } /** * Sets the alpha value that should be applied to the image. * * @param alpha the alpha value that should be applied to the image * * @see #getImageAlpha() */ @RemotableViewMethod public void setImageAlpha(int alpha) { setAlpha(alpha); } /** * Sets the alpha value that should be applied to the image. * * @param alpha the alpha value that should be applied to the image * * @deprecated use #setImageAlpha(int) instead */ @Deprecated @RemotableViewMethod public void setAlpha(int alpha) { alpha &= 0xFF; // keep it legal if (mAlpha != alpha) { mAlpha = alpha; mColorMod = true; applyColorMod(); invalidate(); } } private void applyColorMod() { // Only mutate and apply when modifications have occurred. This should // not reset the mColorMod flag, since these filters need to be // re-applied if the Drawable is changed. if (mDrawable != null && mColorMod) { mDrawable = mDrawable.mutate(); mDrawable.setColorFilter(mColorFilter); mDrawable.setAlpha(mAlpha * mViewAlphaScale >> 8); } } @RemotableViewMethod @Override public void setVisibility(int visibility) { super.setVisibility(visibility); if (mDrawable != null) { mDrawable.setVisible(visibility == VISIBLE, false); } } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); if (mDrawable != null) { mDrawable.setVisible(getVisibility() == VISIBLE, false); } } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); if (mDrawable != null) { mDrawable.setVisible(false, false); } } @Override public void onInitializeAccessibilityEvent(AccessibilityEvent event) { super.onInitializeAccessibilityEvent(event); event.setClassName(ImageView.class.getName()); } @Override public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { super.onInitializeAccessibilityNodeInfo(info); info.setClassName(ImageView.class.getName()); } }