Material Design Team d8cc690b51 [ExposedDropdownMenu][A11y] Add keyboard support for dropdown menus
PiperOrigin-RevId: 788007779
2025-07-28 17:10:55 +00:00

664 lines
24 KiB
Java

/*
* Copyright (C) 2019 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
*
* http://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.textfield;
import com.google.android.material.R;
import static com.google.android.material.theme.overlay.MaterialThemeOverlay.wrap;
import android.accessibilityservice.AccessibilityServiceInfo;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.Rect;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.RippleDrawable;
import androidx.appcompat.widget.AppCompatAutoCompleteTextView;
import androidx.appcompat.widget.ListPopupWindow;
import android.text.InputType;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.view.ViewParent;
import android.view.accessibility.AccessibilityManager;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Filterable;
import android.widget.ListAdapter;
import android.widget.TextView;
import androidx.annotation.ArrayRes;
import androidx.annotation.ColorInt;
import androidx.annotation.LayoutRes;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.VisibleForTesting;
import com.google.android.material.color.MaterialColors;
import com.google.android.material.internal.ManufacturerUtils;
import com.google.android.material.internal.ThemeEnforcement;
import com.google.android.material.resources.MaterialResources;
import com.google.android.material.shape.MaterialShapeDrawable;
import java.util.List;
/**
* A special sub-class of {@link android.widget.AutoCompleteTextView} that is auto-inflated so that
* auto-complete text fields (e.g., for an Exposed Dropdown Menu) are accessible when being
* interacted through a screen reader.
*
* <p>The {@link ListPopupWindow} of the {@link android.widget.AutoCompleteTextView} is not modal,
* so it does not grab accessibility focus. The {@link MaterialAutoCompleteTextView} changes that by
* having a modal {@link ListPopupWindow} that is displayed instead of the non-modal one, so that
* the first item of the popup is automatically focused. This simulates the behavior of the {@link
* android.widget.Spinner}.
*/
public class MaterialAutoCompleteTextView extends AppCompatAutoCompleteTextView {
private static final int MAX_ITEMS_MEASURED = 15;
private static final String SWITCH_ACCESS_ACTIVITY_NAME = "SwitchAccess";
@NonNull private final ListPopupWindow modalListPopup;
@Nullable private final AccessibilityManager accessibilityManager;
@NonNull private final Rect tempRect = new Rect();
@LayoutRes private final int simpleItemLayout;
private final float popupElevation;
@Nullable private ColorStateList dropDownBackgroundTint;
private int simpleItemSelectedColor;
@Nullable private ColorStateList simpleItemSelectedRippleColor;
public MaterialAutoCompleteTextView(@NonNull Context context) {
this(context, null);
}
public MaterialAutoCompleteTextView(
@NonNull Context context, @Nullable AttributeSet attributeSet) {
this(context, attributeSet, androidx.appcompat.R.attr.autoCompleteTextViewStyle);
}
public MaterialAutoCompleteTextView(
@NonNull Context context, @Nullable AttributeSet attributeSet, int defStyleAttr) {
super(wrap(context, attributeSet, defStyleAttr, 0), attributeSet, defStyleAttr);
// Ensure we are using the correctly themed context rather than the context that was passed in.
context = getContext();
TypedArray attributes =
ThemeEnforcement.obtainStyledAttributes(
context,
attributeSet,
R.styleable.MaterialAutoCompleteTextView,
defStyleAttr,
androidx.appcompat.R.style.Widget_AppCompat_AutoCompleteTextView);
// Due to a framework bug, setting android:inputType="none" on xml has no effect. Therefore,
// we check it here in case the autoCompleteTextView should be non-editable.
if (attributes.hasValue(R.styleable.MaterialAutoCompleteTextView_android_inputType)) {
int inputType =
attributes.getInt(
R.styleable.MaterialAutoCompleteTextView_android_inputType, InputType.TYPE_NULL);
if (inputType == InputType.TYPE_NULL) {
setKeyListener(null);
}
}
simpleItemLayout =
attributes.getResourceId(
R.styleable.MaterialAutoCompleteTextView_simpleItemLayout,
R.layout.mtrl_auto_complete_simple_item);
popupElevation =
attributes.getDimensionPixelOffset(
R.styleable.MaterialAutoCompleteTextView_android_popupElevation,
R.dimen.mtrl_exposed_dropdown_menu_popup_elevation);
if (attributes.hasValue(R.styleable.MaterialAutoCompleteTextView_dropDownBackgroundTint)) {
dropDownBackgroundTint =
ColorStateList.valueOf(
attributes.getColor(
R.styleable.MaterialAutoCompleteTextView_dropDownBackgroundTint,
Color.TRANSPARENT));
}
simpleItemSelectedColor =
attributes.getColor(
R.styleable.MaterialAutoCompleteTextView_simpleItemSelectedColor, Color.TRANSPARENT);
simpleItemSelectedRippleColor =
MaterialResources.getColorStateList(
context,
attributes,
R.styleable.MaterialAutoCompleteTextView_simpleItemSelectedRippleColor);
accessibilityManager =
(AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
modalListPopup = new ListPopupWindow(context);
modalListPopup.setModal(true);
modalListPopup.setAnchorView(this);
modalListPopup.setInputMethodMode(ListPopupWindow.INPUT_METHOD_NOT_NEEDED);
modalListPopup.setAdapter(getAdapter());
modalListPopup.setOnItemClickListener(
new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View selectedView, int position, long id) {
Object selectedItem =
position < 0 ? modalListPopup.getSelectedItem() : getAdapter().getItem(position);
setText(convertSelectionToString(selectedItem), false);
OnItemClickListener userOnItemClickListener = getOnItemClickListener();
if (userOnItemClickListener != null) {
if (selectedView == null || position < 0) {
selectedView = modalListPopup.getSelectedView();
position = modalListPopup.getSelectedItemPosition();
id = modalListPopup.getSelectedItemId();
}
userOnItemClickListener.onItemClick(
modalListPopup.getListView(), selectedView, position, id);
}
modalListPopup.dismiss();
}
});
if (attributes.hasValue(R.styleable.MaterialAutoCompleteTextView_simpleItems)) {
setSimpleItems(
attributes.getResourceId(R.styleable.MaterialAutoCompleteTextView_simpleItems, 0));
}
attributes.recycle();
}
@Override
public void showDropDown() {
if (isPopupRequired()) {
modalListPopup.show();
} else {
super.showDropDown();
}
}
@Override
public void dismissDropDown() {
if (isPopupRequired()) {
modalListPopup.dismiss();
} else {
super.dismissDropDown();
}
}
@Override
public boolean onKeyDown(int keyCode, @NonNull KeyEvent event) {
if (shouldShowPopup(keyCode)) {
TextInputLayout textInputLayout = findTextInputLayoutAncestor();
if (textInputLayout != null) {
// A click on the end icon will show the dropdown and animate the icon
// Note that View.performClick() is a programmatic action that works even if the view is
// not clickable.
textInputLayout.getEndIconView().performClick();
}
return true;
}
return super.onKeyDown(keyCode, event);
}
/**
* Determines whether the dropdown should be shown based on the key press.
*
* <p>If the view is editable and single-line, the dropdown is shown only for the Enter or D-pad
* Center keys.
*
* <p>If the view is not editable, the dropdown is shown if the user presses the Enter, D-pad
* Center, or Space keys.
*/
@VisibleForTesting
boolean shouldShowPopup(int keyCode) {
boolean isEnterKey =
keyCode == KeyEvent.KEYCODE_ENTER || keyCode == KeyEvent.KEYCODE_DPAD_CENTER;
boolean isSpaceKey = keyCode == KeyEvent.KEYCODE_SPACE;
boolean isEditable = getKeyListener() != null;
if (isEditable) {
return isEnterKey && getMaxLines() == 1;
} else {
return isEnterKey || isSpaceKey;
}
}
@Override
public void onWindowFocusChanged(boolean hasWindowFocus) {
if (isPopupRequired()) {
// Do not dismissDropDown if touch exploration or switch access is enabled, in case the window
// lost focus in favor of the modalListPopup.
return;
}
super.onWindowFocusChanged(hasWindowFocus);
}
private boolean isPopupRequired() {
return isTouchExplorationEnabled() || isSwitchAccessEnabled();
}
private boolean isTouchExplorationEnabled() {
return accessibilityManager != null && accessibilityManager.isTouchExplorationEnabled();
}
private boolean isSwitchAccessEnabled() {
if (accessibilityManager == null || !accessibilityManager.isEnabled()) {
return false;
}
List<AccessibilityServiceInfo> accessibilityServiceInfos =
accessibilityManager.getEnabledAccessibilityServiceList(
AccessibilityServiceInfo.FEEDBACK_GENERIC);
if (accessibilityServiceInfos != null) {
for (AccessibilityServiceInfo info : accessibilityServiceInfos) {
if (info.getSettingsActivityName() != null
&& info.getSettingsActivityName().contains(SWITCH_ACCESS_ACTIVITY_NAME)) {
return true;
}
}
}
return false;
}
@Override
public <T extends ListAdapter & Filterable> void setAdapter(@Nullable T adapter) {
super.setAdapter(adapter);
modalListPopup.setAdapter(getAdapter());
}
@Override
public void setRawInputType(int type) {
super.setRawInputType(type);
onInputTypeChanged();
}
@Override
public void setOnItemSelectedListener(@Nullable OnItemSelectedListener listener) {
super.setOnItemSelectedListener(listener);
modalListPopup.setOnItemSelectedListener(getOnItemSelectedListener());
}
/**
* Sets the simple string items of auto-completion with the given string array resource. This
* method will create a default {@link ArrayAdapter} with a default item layout specified by
* {@code R.attr.simpleItemLayout} to display auto-complete items.
*
* @see #setSimpleItems(String[])
* @see #setAdapter(ListAdapter)
*/
public void setSimpleItems(@ArrayRes int stringArrayResId) {
setSimpleItems(getResources().getStringArray(stringArrayResId));
}
/**
* Sets the simple string items of auto-completion with the given string array. This method will
* create a default {@link ArrayAdapter} with a default item layout specified by
* {@code R.attr.simpleItemLayout} to display auto-complete items.
*
* @see #setSimpleItems(int)
* @see #setAdapter(ListAdapter)
*/
public void setSimpleItems(@NonNull String[] stringArray) {
setAdapter(new MaterialArrayAdapter<>(getContext(), simpleItemLayout, stringArray));
}
/**
* Sets the color of the popup dropdown container. It will take effect only if the popup
* background is a {@link MaterialShapeDrawable}, which is the default when using a Material
* theme.
*
* @param dropDownBackgroundColor the popup dropdown container color
* @see #setDropDownBackgroundTintList(ColorStateList)
* @see #getDropDownBackgroundTintList()
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_dropDownBackgroundTint
*/
public void setDropDownBackgroundTint(@ColorInt int dropDownBackgroundColor) {
setDropDownBackgroundTintList(ColorStateList.valueOf(dropDownBackgroundColor));
}
/**
* Sets the color of the popup dropdown container. It will take effect only if the popup
* background is a {@link MaterialShapeDrawable}, which is the default when using a Material
* theme.
*
* @param dropDownBackgroundTint the popup dropdown container tint as a {@link ColorStateList}
* object.
* @see #setDropDownBackgroundTint(int)
* @see #getDropDownBackgroundTintList()
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_dropDownBackgroundTint
*/
public void setDropDownBackgroundTintList(@Nullable ColorStateList dropDownBackgroundTint) {
this.dropDownBackgroundTint = dropDownBackgroundTint;
Drawable dropDownBackground = getDropDownBackground();
if (dropDownBackground instanceof MaterialShapeDrawable) {
((MaterialShapeDrawable) dropDownBackground).setFillColor(this.dropDownBackgroundTint);
}
}
/**
* Returns the color of the popup dropdown container.
*
* @see #setDropDownBackgroundTint(int)
* @see #setDropDownBackgroundTintList(ColorStateList)
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_dropDownBackgroundTint
*/
@Nullable
public ColorStateList getDropDownBackgroundTintList() {
return dropDownBackgroundTint;
}
/**
* Sets the color of the default selected popup dropdown item to be used along with
* {@code R.attr.simpleItemLayout}.
*
* @param simpleItemSelectedColor the selected item color
* @see #getSimpleItemSelectedColor()
* @see #setSimpleItems(int)
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_simpleItemSelectedColor
*/
public void setSimpleItemSelectedColor(int simpleItemSelectedColor) {
this.simpleItemSelectedColor = simpleItemSelectedColor;
if (getAdapter() instanceof MaterialArrayAdapter) {
((MaterialArrayAdapter) getAdapter()).updateSelectedItemColorStateList();
}
}
/**
* Returns the color of the default selected popup dropdown item.
*
* @see #setSimpleItemSelectedColor(int)
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_simpleItemSelectedColor
*/
public int getSimpleItemSelectedColor() {
return simpleItemSelectedColor;
}
/**
* Sets the ripple color of the selected popup dropdown item to be used along with
* {@code R.attr.simpleItemLayout}.
*
* @param simpleItemSelectedRippleColor the ripple color state list
* @see #getSimpleItemSelectedRippleColor()
* @see #setSimpleItems(int)
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_simpleItemSelectedRippleColor
*/
public void setSimpleItemSelectedRippleColor(
@Nullable ColorStateList simpleItemSelectedRippleColor) {
this.simpleItemSelectedRippleColor = simpleItemSelectedRippleColor;
if (getAdapter() instanceof MaterialArrayAdapter) {
((MaterialArrayAdapter) getAdapter()).updateSelectedItemColorStateList();
}
}
/**
* Returns the ripple color of the default selected popup dropdown item, or null if not set.
*
* @see #setSimpleItemSelectedRippleColor(ColorStateList)
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_simpleItemSelectedRippleColor
*/
@Nullable
public ColorStateList getSimpleItemSelectedRippleColor() {
return simpleItemSelectedRippleColor;
}
@Override
public void setDropDownBackgroundDrawable(Drawable d) {
super.setDropDownBackgroundDrawable(d);
if (modalListPopup != null) {
modalListPopup.setBackgroundDrawable(d);
}
}
/**
* Returns the elevation of the dropdown popup.
*
* @attr ref
* com.google.android.material.R.styleable#MaterialAutoCompleteTextView_android_popupElevation
*/
public float getPopupElevation() {
return popupElevation;
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
// Meizu devices expect TextView#mHintLayout to be non-null if TextView#getHint() is non-null.
// In order to avoid crashing, we force the creation of the layout by setting an empty non-null
// hint.
TextInputLayout layout = findTextInputLayoutAncestor();
if (layout != null
&& layout.isProvidingHint()
&& super.getHint() == null
&& ManufacturerUtils.isMeizuDevice()) {
setHint("");
}
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
modalListPopup.dismiss();
}
@Nullable
@Override
public CharSequence getHint() {
// Certain test frameworks expect the actionable element to expose its hint as a label. Retrieve
// the hint from the TextInputLayout when it's providing it.
TextInputLayout textInputLayout = findTextInputLayoutAncestor();
if (textInputLayout != null && textInputLayout.isProvidingHint()) {
return textInputLayout.getHint();
}
return super.getHint();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
// Similar to a Spinner, make sure the view's width is at minimum the width of the largest
// dropdown item.
if (MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.AT_MOST) {
final int measuredWidth = getMeasuredWidth();
setMeasuredDimension(
Math.min(
Math.max(measuredWidth, measureContentWidth()),
MeasureSpec.getSize(widthMeasureSpec)),
getMeasuredHeight());
}
}
private int measureContentWidth() {
ListAdapter adapter = getAdapter();
TextInputLayout textInputLayout = findTextInputLayoutAncestor();
if (adapter == null || textInputLayout == null) {
return 0;
}
int width = 0;
View itemView = null;
int itemType = 0;
final int widthMeasureSpec =
MeasureSpec.makeMeasureSpec(getMeasuredWidth(), MeasureSpec.UNSPECIFIED);
final int heightMeasureSpec =
MeasureSpec.makeMeasureSpec(getMeasuredHeight(), MeasureSpec.UNSPECIFIED);
// Cap the number of items that will be measured.
int start = Math.max(0, modalListPopup.getSelectedItemPosition());
final int end = Math.min(adapter.getCount(), start + MAX_ITEMS_MEASURED);
start = Math.max(0, end - MAX_ITEMS_MEASURED);
for (int i = start; i < end; i++) {
final int positionType = adapter.getItemViewType(i);
if (positionType != itemType) {
itemType = positionType;
itemView = null;
}
itemView = adapter.getView(i, itemView, textInputLayout);
if (itemView.getLayoutParams() == null) {
itemView.setLayoutParams(new LayoutParams(
LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT));
}
itemView.measure(widthMeasureSpec, heightMeasureSpec);
width = Math.max(width, itemView.getMeasuredWidth());
}
// Add background padding to measured width.
Drawable background = modalListPopup.getBackground();
if (background != null) {
background.getPadding(tempRect);
width += tempRect.left + tempRect.right;
}
// Add icon width to measured width.
int iconWidth = textInputLayout.getEndIconView().getMeasuredWidth();
width += iconWidth;
return width;
}
private void onInputTypeChanged() {
TextInputLayout textInputLayout = findTextInputLayoutAncestor();
if (textInputLayout != null) {
textInputLayout.updateEditTextBoxBackgroundIfNeeded();
}
}
@Nullable
private TextInputLayout findTextInputLayoutAncestor() {
ViewParent parent = getParent();
while (parent != null) {
if (parent instanceof TextInputLayout) {
return (TextInputLayout) parent;
}
parent = parent.getParent();
}
return null;
}
/** ArrayAdapter for the {@link MaterialAutoCompleteTextView}. */
private class MaterialArrayAdapter<T> extends ArrayAdapter<String> {
@Nullable private ColorStateList selectedItemRippleOverlaidColor;
@Nullable private ColorStateList pressedRippleColor;
MaterialArrayAdapter(
@NonNull Context context, int resource, @NonNull String[] objects) {
super(context, resource, objects);
updateSelectedItemColorStateList();
}
void updateSelectedItemColorStateList() {
pressedRippleColor = sanitizeDropdownItemSelectedRippleColor();
selectedItemRippleOverlaidColor = createItemSelectedColorStateList();
}
@Override
public View getView(int position, @Nullable View convertView, ViewGroup parent) {
View view = super.getView(position, convertView, parent);
if (view instanceof TextView) {
TextView textView = (TextView) view;
boolean isSelectedItem = getText().toString().contentEquals(textView.getText());
textView.setBackground(isSelectedItem ? getSelectedItemDrawable() : null);
}
return view;
}
@Nullable
private Drawable getSelectedItemDrawable() {
if (!hasSelectedColor()) {
return null;
}
// The adapter calls getView with the same position multiple times with different views,
// meaning we can't know which view is actually being used to show the list item. We need to
// create the drawable on every call, otherwise there can be a race condition causing the
// background color to not be updated to the right state.
Drawable colorDrawable = new ColorDrawable(simpleItemSelectedColor);
if (pressedRippleColor != null) {
// The ListPopupWindow takes over the states of its list items in order to implement its
// own ripple. That makes the RippleDrawable not work as expected, i.e. it will respond to
// pressed states, but not to other states like focused and hovered. To solve that, we
// create the selectedItemRippleOverlaidColor that will work in those missing states, making
// the selected list item stateful as expected.
colorDrawable.setTintList(selectedItemRippleOverlaidColor);
return new RippleDrawable(pressedRippleColor, colorDrawable, null);
} else {
return colorDrawable;
}
}
@Nullable
private ColorStateList createItemSelectedColorStateList() {
if (!hasSelectedColor() || !hasSelectedRippleColor()) {
return null;
}
int[] stateHovered = new int[] {android.R.attr.state_hovered, -android.R.attr.state_pressed};
int[] stateSelected =
new int[] {android.R.attr.state_selected, -android.R.attr.state_pressed};
int colorSelected =
simpleItemSelectedRippleColor.getColorForState(stateSelected, Color.TRANSPARENT);
int colorHovered =
simpleItemSelectedRippleColor.getColorForState(stateHovered, Color.TRANSPARENT);
// Use ripple colors overlaid over selected color.
int[] colors =
new int[] {
MaterialColors.layer(simpleItemSelectedColor, colorSelected),
MaterialColors.layer(simpleItemSelectedColor, colorHovered),
simpleItemSelectedColor
};
int[][] states = new int[][] {stateSelected, stateHovered, new int[] {}};
return new ColorStateList(states, colors);
}
private ColorStateList sanitizeDropdownItemSelectedRippleColor() {
if (!hasSelectedRippleColor()) {
return null;
}
// We need to ensure that the ripple drawable we create will show a color only for the pressed
// state so that the final ripple over the item view will be the correct color.
int[] statePressed = new int[] {android.R.attr.state_pressed};
int[] colors =
new int[] {
simpleItemSelectedRippleColor.getColorForState(statePressed, Color.TRANSPARENT),
Color.TRANSPARENT
};
int[][] states = new int[][] {statePressed, new int[] {}};
return new ColorStateList(states, colors);
}
private boolean hasSelectedColor() {
return simpleItemSelectedColor != Color.TRANSPARENT;
}
private boolean hasSelectedRippleColor() {
return simpleItemSelectedRippleColor != null;
}
}
}