2025-02-25 19:33:33 +00:00

308 lines
11 KiB
Java

/*
* Copyright 2022 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.android.material.carousel;
import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.accessibility.AccessibilityNodeInfo;
import android.widget.FrameLayout;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RestrictTo;
import androidx.annotation.RestrictTo.Scope;
import androidx.annotation.VisibleForTesting;
import androidx.core.math.MathUtils;
import com.google.android.material.animation.AnimationUtils;
import com.google.android.material.shape.AbsoluteCornerSize;
import com.google.android.material.shape.ClampedCornerSize;
import com.google.android.material.shape.ShapeAppearanceModel;
import com.google.android.material.shape.Shapeable;
import com.google.android.material.shape.ShapeableDelegate;
/** A {@link FrameLayout} than is able to mask itself and all children. */
public class MaskableFrameLayout extends FrameLayout implements Maskable, Shapeable {
private static final int NOT_SET = -1;
private float maskXPercentage = NOT_SET;
private final RectF maskRect = new RectF();
private final Rect screenBoundsRect = new Rect();
@Nullable private OnMaskChangedListener onMaskChangedListener;
@NonNull private ShapeAppearanceModel shapeAppearanceModel;
private final ShapeableDelegate shapeableDelegate = ShapeableDelegate.create(this);
@Nullable private Boolean savedForceCompatClippingEnabled = null;
@Nullable private OnHoverListener hoverListener;
private boolean isHovered = false;
public MaskableFrameLayout(@NonNull Context context) {
this(context, null);
}
public MaskableFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
this(context, attrs, 0);
}
public MaskableFrameLayout(
@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
setShapeAppearanceModel(
ShapeAppearanceModel.builder(context, attrs, defStyleAttr, 0, 0).build());
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
if (maskXPercentage != NOT_SET) {
updateMaskRectForMaskXPercentage();
}
}
@Override
public void getFocusedRect(Rect r) {
r.set((int) maskRect.left, (int) maskRect.top, (int) maskRect.right, (int) maskRect.bottom);
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
// Restore any saved force compat clipping setting.
if (savedForceCompatClippingEnabled != null) {
shapeableDelegate.setForceCompatClippingEnabled(this, savedForceCompatClippingEnabled);
}
}
@Override
protected void onDetachedFromWindow() {
// When detaching from the window, force canvas clipping to avoid any transitions from releasing
// the mask outline set by the MaskableDelegate's ViewOutlineProvider, if any.
savedForceCompatClippingEnabled = shapeableDelegate.isForceCompatClippingEnabled();
shapeableDelegate.setForceCompatClippingEnabled(this, true);
super.onDetachedFromWindow();
}
@Override
public void setShapeAppearanceModel(@NonNull ShapeAppearanceModel shapeAppearanceModel) {
this.shapeAppearanceModel =
shapeAppearanceModel.withTransformedCornerSizes(
cornerSize -> {
if (cornerSize instanceof AbsoluteCornerSize) {
// Enforce that the corners of the shape appearance are never larger than half the
// width of the shortest edge. As the size of the mask changes, we never want the
// corners to be larger than half the width or height of this view.
return ClampedCornerSize.createFromCornerSize((AbsoluteCornerSize) cornerSize);
} else {
// Relative corner size already enforces a max size based on shortest edge.
return cornerSize;
}
});
shapeableDelegate.onShapeAppearanceChanged(this, this.shapeAppearanceModel);
}
@NonNull
@Override
public ShapeAppearanceModel getShapeAppearanceModel() {
return shapeAppearanceModel;
}
/**
* Sets the percentage by which this {@link View} masks by along the x axis.
*
* @param percentage 0 when this view is fully unmasked. 1 when this view is fully masked.
* @deprecated This is no longer used as {@link CarouselLayoutManager} calculates its own mask
* percentages.
*/
@Override
@Deprecated
public void setMaskXPercentage(float percentage) {
percentage = MathUtils.clamp(percentage, 0F, 1F);
if (maskXPercentage != percentage) {
this.maskXPercentage = percentage;
updateMaskRectForMaskXPercentage();
}
}
private void updateMaskRectForMaskXPercentage() {
if (maskXPercentage != NOT_SET) {
// Translate the percentage into an actual pixel value of how much of this view should be
// masked away.
float maskWidth = AnimationUtils.lerp(0f, getWidth() / 2F, 0f, 1f, maskXPercentage);
setMaskRectF(new RectF(maskWidth, 0F, (getWidth() - maskWidth), getHeight()));
}
}
/**
* Sets the {@link RectF} that this {@link View} will be masked by.
*
* @param maskRect a rect in the view's coordinates to mask by
*/
@Override
public void setMaskRectF(@NonNull RectF maskRect) {
this.maskRect.set(maskRect);
onMaskChanged();
}
/**
* Gets the percentage by which this {@link View} is masked by along the x axis.
*
* @return a float between 0 and 1 where 0 is fully unmasked and 1 is fully masked.
* @deprecated This is no longer used as {@link CarouselLayoutManager} calculates its own mask
* percentages.
*/
@Override
@Deprecated
public float getMaskXPercentage() {
return maskXPercentage;
}
/** Gets a {@link RectF} that this {@link View} is masked itself by. */
@NonNull
@Override
public RectF getMaskRectF() {
return maskRect;
}
/**
* Sets an {@link OnMaskChangedListener}.
*
* @param onMaskChangedListener a listener to receive callbacks for changes in the mask or null
* to clear the listener.
*/
@Override
public void setOnMaskChangedListener(@Nullable OnMaskChangedListener onMaskChangedListener) {
this.onMaskChangedListener = onMaskChangedListener;
}
private void onMaskChanged() {
shapeableDelegate.onMaskChanged(this, maskRect);
if (onMaskChangedListener != null) {
onMaskChangedListener.onMaskChanged(maskRect);
}
}
/**
* Set whether this view should always use canvas clipping to clip to its masked shape.
*
* @hide
*/
@VisibleForTesting
@RestrictTo(Scope.LIBRARY_GROUP)
public void setForceCompatClipping(boolean forceCompatClipping) {
shapeableDelegate.setForceCompatClippingEnabled(this, forceCompatClipping);
}
@SuppressLint("ClickableViewAccessibility")
@Override
public boolean onTouchEvent(MotionEvent event) {
// Only handle touch events that are within the masked bounds of this view.
if (!maskRect.isEmpty() && event.getAction() == MotionEvent.ACTION_DOWN) {
float x = event.getX();
float y = event.getY();
if (!maskRect.contains(x, y)) {
return false;
}
}
return super.onTouchEvent(event);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent event) {
// Intercept touch events outside the masked bounds and prevent them from
// reaching the children.
if (!maskRect.isEmpty()) {
float x = event.getX();
float y = event.getY();
if (!maskRect.contains(x, y)) {
return true; // Intercept touch events outside the mask
}
}
return super.onInterceptTouchEvent(event);
}
@Override
protected void dispatchDraw(Canvas canvas) {
shapeableDelegate.maybeClip(canvas, super::dispatchDraw);
}
@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(info);
// Note: This is a workaround until b/273752775 is resolved. A11y bounds should be set by the
// a11y framework.
info.getBoundsInScreen(screenBoundsRect);
// If the child starts from a negative x, the screen bounds are already cut off at the
// parent so there is no need to reduce the screen bound's left bound. Similarly for negative y.
if (getX() > 0) {
screenBoundsRect.left = (int) (screenBoundsRect.left + maskRect.left);
}
if (getY() > 0) {
screenBoundsRect.top = (int) (screenBoundsRect.top + maskRect.top);
}
screenBoundsRect.right = screenBoundsRect.left + Math.round(maskRect.width());
screenBoundsRect.bottom = screenBoundsRect.top + Math.round(maskRect.height());
info.setBoundsInScreen(screenBoundsRect);
}
@Override
public void setOnHoverListener(@Nullable OnHoverListener l) {
hoverListener = l;
}
@Override
public boolean onHoverEvent(MotionEvent event) {
// Only handle hover events that are within the masked bounds of this view.
int action = event.getAction();
if (!maskRect.isEmpty()
&& (action == MotionEvent.ACTION_HOVER_ENTER
|| action == MotionEvent.ACTION_HOVER_EXIT
|| action== MotionEvent.ACTION_HOVER_MOVE)) {
float x = event.getX();
float y = event.getY();
if (!maskRect.contains(x, y)) {
if (isHovered && hoverListener != null) {
event.setAction(MotionEvent.ACTION_HOVER_EXIT);
hoverListener.onHover(this, event);
}
isHovered = false;
return false;
}
}
if (hoverListener != null) {
// If the MaskableFrameLayout is currently not hovered and the action is a move, it
// should be changed to an enter action
if (!isHovered && action == MotionEvent.ACTION_HOVER_MOVE) {
event.setAction(MotionEvent.ACTION_HOVER_ENTER);
isHovered = true;
}
if (action == MotionEvent.ACTION_HOVER_MOVE
|| action == MotionEvent.ACTION_HOVER_ENTER) {
isHovered = true;
}
hoverListener.onHover(this, event);
}
return super.onHoverEvent(event);
}
}