Child views are drawn in a stack, with the most recently added child on top.
* The size of the FrameLayout is the size of its largest child (plus padding), visible
* or not (if the FrameLayout's parent permits). Views that are {@link android.view.View#GONE} are
* used for sizing
* only if {@link #setMeasureAllChildren(boolean) setConsiderGoneChildrenWhenMeasuring()}
* is set to true.
*
* @attr ref android.R.styleable#FrameLayout_foreground
* @attr ref android.R.styleable#FrameLayout_foregroundGravity
* @attr ref android.R.styleable#FrameLayout_measureAllChildren
*/
@RemoteView
public class FrameLayout extends ViewGroup {
private static final int DEFAULT_CHILD_GRAVITY = Gravity.TOP | Gravity.START;
@ViewDebug.ExportedProperty(category = "measurement")
boolean mMeasureAllChildren = false;
@ViewDebug.ExportedProperty(category = "drawing")
private Drawable mForeground;
private ColorStateList mForegroundTintList = null;
private PorterDuff.Mode mForegroundTintMode = null;
private boolean mHasForegroundTint = false;
private boolean mHasForegroundTintMode = false;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingLeft = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingTop = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingRight = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingBottom = 0;
private final Rect mSelfBounds = new Rect();
private final Rect mOverlayBounds = new Rect();
@ViewDebug.ExportedProperty(category = "drawing")
private int mForegroundGravity = Gravity.FILL;
/** {@hide} */
@ViewDebug.ExportedProperty(category = "drawing")
protected boolean mForegroundInPadding = true;
boolean mForegroundBoundsChanged = false;
private final ArrayList
* Subsequent calls to {@link #setForeground(Drawable)} will automatically
* mutate the drawable and apply the specified tint and tint mode using
* {@link Drawable#setTintList(ColorStateList)}.
*
* @param tint the tint to apply, may be {@code null} to clear tint
*
* @attr ref android.R.styleable#FrameLayout_foregroundTint
* @see #getForegroundTintList()
* @see Drawable#setTintList(ColorStateList)
*/
public void setForegroundTintList(@Nullable ColorStateList tint) {
mForegroundTintList = tint;
mHasForegroundTint = true;
applyForegroundTint();
}
/**
* @return the tint applied to the foreground drawable
* @attr ref android.R.styleable#FrameLayout_foregroundTint
* @see #setForegroundTintList(ColorStateList)
*/
@Nullable
public ColorStateList getForegroundTintList() {
return mForegroundTintList;
}
/**
* Specifies the blending mode used to apply the tint specified by
* {@link #setForegroundTintList(ColorStateList)}} to the foreground drawable.
* The default mode is {@link PorterDuff.Mode#SRC_IN}.
*
* @param tintMode the blending mode used to apply the tint, may be
* {@code null} to clear tint
* @attr ref android.R.styleable#FrameLayout_foregroundTintMode
* @see #getForegroundTintMode()
* @see Drawable#setTintMode(PorterDuff.Mode)
*/
public void setForegroundTintMode(@Nullable PorterDuff.Mode tintMode) {
mForegroundTintMode = tintMode;
mHasForegroundTintMode = true;
applyForegroundTint();
}
/**
* @return the blending mode used to apply the tint to the foreground
* drawable
* @attr ref android.R.styleable#FrameLayout_foregroundTintMode
* @see #setForegroundTintMode(PorterDuff.Mode)
*/
@Nullable
public PorterDuff.Mode getForegroundTintMode() {
return mForegroundTintMode;
}
private void applyForegroundTint() {
if (mForeground != null && (mHasForegroundTint || mHasForegroundTintMode)) {
mForeground = mForeground.mutate();
if (mHasForegroundTint) {
mForeground.setTintList(mForegroundTintList);
}
if (mHasForegroundTintMode) {
mForeground.setTintMode(mForegroundTintMode);
}
// The drawable (or one of its children) may not have been
// stateful before applying the tint, so let's try again.
if (mForeground.isStateful()) {
mForeground.setState(getDrawableState());
}
}
}
int getPaddingLeftWithForeground() {
return mForegroundInPadding ? Math.max(mPaddingLeft, mForegroundPaddingLeft) :
mPaddingLeft + mForegroundPaddingLeft;
}
int getPaddingRightWithForeground() {
return mForegroundInPadding ? Math.max(mPaddingRight, mForegroundPaddingRight) :
mPaddingRight + mForegroundPaddingRight;
}
private int getPaddingTopWithForeground() {
return mForegroundInPadding ? Math.max(mPaddingTop, mForegroundPaddingTop) :
mPaddingTop + mForegroundPaddingTop;
}
private int getPaddingBottomWithForeground() {
return mForegroundInPadding ? Math.max(mPaddingBottom, mForegroundPaddingBottom) :
mPaddingBottom + mForegroundPaddingBottom;
}
/**
* {@inheritDoc}
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int count = getChildCount();
final boolean measureMatchParentChildren =
MeasureSpec.getMode(widthMeasureSpec) != MeasureSpec.EXACTLY ||
MeasureSpec.getMode(heightMeasureSpec) != MeasureSpec.EXACTLY;
mMatchParentChildren.clear();
int maxHeight = 0;
int maxWidth = 0;
int childState = 0;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (mMeasureAllChildren || child.getVisibility() != GONE) {
measureChildWithMargins(child, widthMeasureSpec, 0, heightMeasureSpec, 0);
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
maxWidth = Math.max(maxWidth,
child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin);
maxHeight = Math.max(maxHeight,
child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin);
childState = combineMeasuredStates(childState, child.getMeasuredState());
if (measureMatchParentChildren) {
if (lp.width == LayoutParams.MATCH_PARENT ||
lp.height == LayoutParams.MATCH_PARENT) {
mMatchParentChildren.add(child);
}
}
}
}
// Account for padding too
maxWidth += getPaddingLeftWithForeground() + getPaddingRightWithForeground();
maxHeight += getPaddingTopWithForeground() + getPaddingBottomWithForeground();
// Check against our minimum height and width
maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight());
maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth());
// Check against our foreground's minimum height and width
final Drawable drawable = getForeground();
if (drawable != null) {
maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
}
setMeasuredDimension(resolveSizeAndState(maxWidth, widthMeasureSpec, childState),
resolveSizeAndState(maxHeight, heightMeasureSpec,
childState << MEASURED_HEIGHT_STATE_SHIFT));
count = mMatchParentChildren.size();
if (count > 1) {
for (int i = 0; i < count; i++) {
final View child = mMatchParentChildren.get(i);
final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
int childWidthMeasureSpec;
int childHeightMeasureSpec;
if (lp.width == LayoutParams.MATCH_PARENT) {
childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(getMeasuredWidth() -
getPaddingLeftWithForeground() - getPaddingRightWithForeground() -
lp.leftMargin - lp.rightMargin,
MeasureSpec.EXACTLY);
} else {
childWidthMeasureSpec = getChildMeasureSpec(widthMeasureSpec,
getPaddingLeftWithForeground() + getPaddingRightWithForeground() +
lp.leftMargin + lp.rightMargin,
lp.width);
}
if (lp.height == LayoutParams.MATCH_PARENT) {
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(getMeasuredHeight() -
getPaddingTopWithForeground() - getPaddingBottomWithForeground() -
lp.topMargin - lp.bottomMargin,
MeasureSpec.EXACTLY);
} else {
childHeightMeasureSpec = getChildMeasureSpec(heightMeasureSpec,
getPaddingTopWithForeground() + getPaddingBottomWithForeground() +
lp.topMargin + lp.bottomMargin,
lp.height);
}
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
}
}
}
/**
* {@inheritDoc}
*/
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
layoutChildren(left, top, right, bottom, false /* no force left gravity */);
}
void layoutChildren(int left, int top, int right, int bottom,
boolean forceLeftGravity) {
final int count = getChildCount();
final int parentLeft = getPaddingLeftWithForeground();
final int parentRight = right - left - getPaddingRightWithForeground();
final int parentTop = getPaddingTopWithForeground();
final int parentBottom = bottom - top - getPaddingBottomWithForeground();
mForegroundBoundsChanged = true;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() != GONE) {
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
final int width = child.getMeasuredWidth();
final int height = child.getMeasuredHeight();
int childLeft;
int childTop;
int gravity = lp.gravity;
if (gravity == -1) {
gravity = DEFAULT_CHILD_GRAVITY;
}
final int layoutDirection = getLayoutDirection();
final int absoluteGravity = Gravity.getAbsoluteGravity(gravity, layoutDirection);
final int verticalGravity = gravity & Gravity.VERTICAL_GRAVITY_MASK;
switch (absoluteGravity & Gravity.HORIZONTAL_GRAVITY_MASK) {
case Gravity.CENTER_HORIZONTAL:
childLeft = parentLeft + (parentRight - parentLeft - width) / 2 +
lp.leftMargin - lp.rightMargin;
break;
case Gravity.RIGHT:
if (!forceLeftGravity) {
childLeft = parentRight - width - lp.rightMargin;
break;
}
case Gravity.LEFT:
default:
childLeft = parentLeft + lp.leftMargin;
}
switch (verticalGravity) {
case Gravity.TOP:
childTop = parentTop + lp.topMargin;
break;
case Gravity.CENTER_VERTICAL:
childTop = parentTop + (parentBottom - parentTop - height) / 2 +
lp.topMargin - lp.bottomMargin;
break;
case Gravity.BOTTOM:
childTop = parentBottom - height - lp.bottomMargin;
break;
default:
childTop = parentTop + lp.topMargin;
}
child.layout(childLeft, childTop, childLeft + width, childTop + height);
}
}
}
/**
* {@inheritDoc}
*/
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mForegroundBoundsChanged = true;
}
/**
* {@inheritDoc}
*/
@Override
public void draw(Canvas canvas) {
super.draw(canvas);
if (mForeground != null) {
final Drawable foreground = mForeground;
if (mForegroundBoundsChanged) {
mForegroundBoundsChanged = false;
final Rect selfBounds = mSelfBounds;
final Rect overlayBounds = mOverlayBounds;
final int w = mRight-mLeft;
final int h = mBottom-mTop;
if (mForegroundInPadding) {
selfBounds.set(0, 0, w, h);
} else {
selfBounds.set(mPaddingLeft, mPaddingTop, w - mPaddingRight, h - mPaddingBottom);
}
final int layoutDirection = getLayoutDirection();
Gravity.apply(mForegroundGravity, foreground.getIntrinsicWidth(),
foreground.getIntrinsicHeight(), selfBounds, overlayBounds,
layoutDirection);
foreground.setBounds(overlayBounds);
}
foreground.draw(canvas);
}
}
/**
* {@inheritDoc}
*/
@Override
public boolean gatherTransparentRegion(Region region) {
boolean opaque = super.gatherTransparentRegion(region);
if (region != null && mForeground != null) {
applyDrawableToTransparentRegion(mForeground, region);
}
return opaque;
}
/**
* Sets whether to consider all children, or just those in
* the VISIBLE or INVISIBLE state, when measuring. Defaults to false.
*
* @param measureAll true to consider children marked GONE, false otherwise.
* Default value is false.
*
* @attr ref android.R.styleable#FrameLayout_measureAllChildren
*/
@android.view.RemotableViewMethod
public void setMeasureAllChildren(boolean measureAll) {
mMeasureAllChildren = measureAll;
}
/**
* Determines whether all children, or just those in the VISIBLE or
* INVISIBLE state, are considered when measuring.
*
* @return Whether all children are considered when measuring.
*
* @deprecated This method is deprecated in favor of
* {@link #getMeasureAllChildren() getMeasureAllChildren()}, which was
* renamed for consistency with
* {@link #setMeasureAllChildren(boolean) setMeasureAllChildren()}.
*/
@Deprecated
public boolean getConsiderGoneChildrenWhenMeasuring() {
return getMeasureAllChildren();
}
/**
* Determines whether all children, or just those in the VISIBLE or
* INVISIBLE state, are considered when measuring.
*
* @return Whether all children are considered when measuring.
*/
public boolean getMeasureAllChildren() {
return mMeasureAllChildren;
}
/**
* {@inheritDoc}
*/
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new FrameLayout.LayoutParams(getContext(), attrs);
}
@Override
public boolean shouldDelayChildPressedState() {
return false;
}
/**
* {@inheritDoc}
*/
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
return p instanceof LayoutParams;
}
@Override
protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
return new LayoutParams(p);
}
@Override
public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
super.onInitializeAccessibilityEvent(event);
event.setClassName(FrameLayout.class.getName());
}
@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(info);
info.setClassName(FrameLayout.class.getName());
}
/**
* Per-child layout information for layouts that support margins.
* See {@link android.R.styleable#FrameLayout_Layout FrameLayout Layout Attributes}
* for a list of all child view attributes that this class supports.
*
* @attr ref android.R.styleable#FrameLayout_Layout_layout_gravity
*/
public static class LayoutParams extends MarginLayoutParams {
/**
* The gravity to apply with the View to which these layout parameters
* are associated.
*
* @see android.view.Gravity
*
* @attr ref android.R.styleable#FrameLayout_Layout_layout_gravity
*/
public int gravity = -1;
/**
* {@inheritDoc}
*/
public LayoutParams(Context c, AttributeSet attrs) {
super(c, attrs);
TypedArray a = c.obtainStyledAttributes(attrs, com.android.internal.R.styleable.FrameLayout_Layout);
gravity = a.getInt(com.android.internal.R.styleable.FrameLayout_Layout_layout_gravity, -1);
a.recycle();
}
/**
* {@inheritDoc}
*/
public LayoutParams(int width, int height) {
super(width, height);
}
/**
* Creates a new set of layout parameters with the specified width, height
* and weight.
*
* @param width the width, either {@link #MATCH_PARENT},
* {@link #WRAP_CONTENT} or a fixed size in pixels
* @param height the height, either {@link #MATCH_PARENT},
* {@link #WRAP_CONTENT} or a fixed size in pixels
* @param gravity the gravity
*
* @see android.view.Gravity
*/
public LayoutParams(int width, int height, int gravity) {
super(width, height);
this.gravity = gravity;
}
/**
* {@inheritDoc}
*/
public LayoutParams(ViewGroup.LayoutParams source) {
super(source);
}
/**
* {@inheritDoc}
*/
public LayoutParams(ViewGroup.MarginLayoutParams source) {
super(source);
}
/**
* Copy constructor. Clones the width, height, margin values, and
* gravity of the source.
*
* @param source The layout params to copy from.
*/
public LayoutParams(LayoutParams source) {
super(source);
this.gravity = source.gravity;
}
}
}