/* * Copyright (C) 2007 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 android.widget; import com.android.internal.R; import com.android.internal.view.menu.ShowableListMenu; import android.annotation.DrawableRes; import android.annotation.Nullable; import android.annotation.Widget; import android.app.AlertDialog; import android.content.Context; import android.content.DialogInterface; import android.content.DialogInterface.OnClickListener; import android.content.res.Resources; import android.content.res.Resources.Theme; import android.content.res.TypedArray; import android.database.DataSetObserver; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.os.Build; import android.os.Parcel; import android.os.Parcelable; import android.util.AttributeSet; import android.util.Log; import android.view.ContextThemeWrapper; import android.view.Gravity; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.view.ViewTreeObserver; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.view.accessibility.AccessibilityNodeInfo; import android.widget.PopupWindow.OnDismissListener; /** * A view that displays one child at a time and lets the user pick among them. * The items in the Spinner come from the {@link Adapter} associated with * this view. * *
See the Spinners guide.
* * @attr ref android.R.styleable#Spinner_dropDownSelector * @attr ref android.R.styleable#Spinner_dropDownWidth * @attr ref android.R.styleable#Spinner_gravity * @attr ref android.R.styleable#Spinner_popupBackground * @attr ref android.R.styleable#Spinner_prompt * @attr ref android.R.styleable#Spinner_spinnerMode * @attr ref android.R.styleable#ListPopupWindow_dropDownVerticalOffset * @attr ref android.R.styleable#ListPopupWindow_dropDownHorizontalOffset */ @Widget public class Spinner extends AbsSpinner implements OnClickListener { private static final String TAG = "Spinner"; // Only measure this many items to get a decent max width. private static final int MAX_ITEMS_MEASURED = 15; /** * Use a dialog window for selecting spinner options. */ public static final int MODE_DIALOG = 0; /** * Use a dropdown anchored to the Spinner for selecting spinner options. */ public static final int MODE_DROPDOWN = 1; /** * Use the theme-supplied value to select the dropdown mode. */ private static final int MODE_THEME = -1; private final Rect mTempRect = new Rect(); /** Context used to inflate the popup window or dialog. */ private final Context mPopupContext; /** Forwarding listener used to implement drag-to-open. */ private ForwardingListener mForwardingListener; /** Temporary holder for setAdapter() calls from the super constructor. */ private SpinnerAdapter mTempAdapter; private SpinnerPopup mPopup; int mDropDownWidth; private int mGravity; private boolean mDisableChildrenWhenDisabled; /** * Constructs a new spinner with the given context's theme. * * @param context The Context the view is running in, through which it can * access the current theme, resources, etc. */ public Spinner(Context context) { this(context, null); } /** * Constructs a new spinner with the given context's theme and the supplied * mode of displaying choices.mode
may be one of
* {@link #MODE_DIALOG} or {@link #MODE_DROPDOWN}.
*
* @param context The Context the view is running in, through which it can
* access the current theme, resources, etc.
* @param mode Constant describing how the user will select choices from
* the spinner.
*
* @see #MODE_DIALOG
* @see #MODE_DROPDOWN
*/
public Spinner(Context context, int mode) {
this(context, null, com.android.internal.R.attr.spinnerStyle, mode);
}
/**
* Constructs a new spinner with the given context's theme and the supplied
* attribute set.
*
* @param context The Context the view is running in, through which it can
* access the current theme, resources, etc.
* @param attrs The attributes of the XML tag that is inflating the view.
*/
public Spinner(Context context, AttributeSet attrs) {
this(context, attrs, com.android.internal.R.attr.spinnerStyle);
}
/**
* Constructs a new spinner with the given context's theme, the supplied
* attribute set, and default style attribute.
*
* @param context The Context the view is running in, through which it can
* access the current theme, resources, etc.
* @param attrs The attributes of the XML tag that is inflating the view.
* @param defStyleAttr An attribute in the current theme that contains a
* reference to a style resource that supplies default
* values for the view. Can be 0 to not look for
* defaults.
*/
public Spinner(Context context, AttributeSet attrs, int defStyleAttr) {
this(context, attrs, defStyleAttr, 0, MODE_THEME);
}
/**
* Constructs a new spinner with the given context's theme, the supplied
* attribute set, and default style attribute. mode
may be one
* of {@link #MODE_DIALOG} or {@link #MODE_DROPDOWN} and determines how the
* user will select choices from the spinner.
*
* @param context The Context the view is running in, through which it can
* access the current theme, resources, etc.
* @param attrs The attributes of the XML tag that is inflating the view.
* @param defStyleAttr An attribute in the current theme that contains a
* reference to a style resource that supplies default
* values for the view. Can be 0 to not look for defaults.
* @param mode Constant describing how the user will select choices from the
* spinner.
*
* @see #MODE_DIALOG
* @see #MODE_DROPDOWN
*/
public Spinner(Context context, AttributeSet attrs, int defStyleAttr, int mode) {
this(context, attrs, defStyleAttr, 0, mode);
}
/**
* Constructs a new spinner with the given context's theme, the supplied
* attribute set, and default styles. mode
may be one of
* {@link #MODE_DIALOG} or {@link #MODE_DROPDOWN} and determines how the
* user will select choices from the spinner.
*
* @param context The Context the view is running in, through which it can
* access the current theme, resources, etc.
* @param attrs The attributes of the XML tag that is inflating the view.
* @param defStyleAttr An attribute in the current theme that contains a
* reference to a style resource that supplies default
* values for the view. Can be 0 to not look for
* defaults.
* @param defStyleRes A resource identifier of a style resource that
* supplies default values for the view, used only if
* defStyleAttr is 0 or can not be found in the theme.
* Can be 0 to not look for defaults.
* @param mode Constant describing how the user will select choices from
* the spinner.
*
* @see #MODE_DIALOG
* @see #MODE_DROPDOWN
*/
public Spinner(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes,
int mode) {
this(context, attrs, defStyleAttr, defStyleRes, mode, null);
}
/**
* Constructs a new spinner with the given context, the supplied attribute
* set, default styles, popup mode (one of {@link #MODE_DIALOG} or
* {@link #MODE_DROPDOWN}), and the theme against which the popup should be
* inflated.
*
* @param context The context against which the view is inflated, which
* provides access to the current theme, resources, etc.
* @param attrs The attributes of the XML tag that is inflating the view.
* @param defStyleAttr An attribute in the current theme that contains a
* reference to a style resource that supplies default
* values for the view. Can be 0 to not look for
* defaults.
* @param defStyleRes A resource identifier of a style resource that
* supplies default values for the view, used only if
* defStyleAttr is 0 or can not be found in the theme.
* Can be 0 to not look for defaults.
* @param mode Constant describing how the user will select choices from
* the spinner.
* @param popupTheme The theme against which the dialog or dropdown popup
* should be inflated. May be {@code null} to use the
* view theme. If set, this will override any value
* specified by
* {@link android.R.styleable#Spinner_popupTheme}.
*
* @see #MODE_DIALOG
* @see #MODE_DROPDOWN
*/
public Spinner(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes, int mode,
Theme popupTheme) {
super(context, attrs, defStyleAttr, defStyleRes);
final TypedArray a = context.obtainStyledAttributes(
attrs, R.styleable.Spinner, defStyleAttr, defStyleRes);
if (popupTheme != null) {
mPopupContext = new ContextThemeWrapper(context, popupTheme);
} else {
final int popupThemeResId = a.getResourceId(R.styleable.Spinner_popupTheme, 0);
if (popupThemeResId != 0) {
mPopupContext = new ContextThemeWrapper(context, popupThemeResId);
} else {
mPopupContext = context;
}
}
if (mode == MODE_THEME) {
mode = a.getInt(R.styleable.Spinner_spinnerMode, MODE_DIALOG);
}
switch (mode) {
case MODE_DIALOG: {
mPopup = new DialogPopup();
mPopup.setPromptText(a.getString(R.styleable.Spinner_prompt));
break;
}
case MODE_DROPDOWN: {
final DropdownPopup popup = new DropdownPopup(
mPopupContext, attrs, defStyleAttr, defStyleRes);
final TypedArray pa = mPopupContext.obtainStyledAttributes(
attrs, R.styleable.Spinner, defStyleAttr, defStyleRes);
mDropDownWidth = pa.getLayoutDimension(R.styleable.Spinner_dropDownWidth,
ViewGroup.LayoutParams.WRAP_CONTENT);
if (pa.hasValueOrEmpty(R.styleable.Spinner_dropDownSelector)) {
popup.setListSelector(pa.getDrawable(
R.styleable.Spinner_dropDownSelector));
}
popup.setBackgroundDrawable(pa.getDrawable(R.styleable.Spinner_popupBackground));
popup.setPromptText(a.getString(R.styleable.Spinner_prompt));
pa.recycle();
mPopup = popup;
mForwardingListener = new ForwardingListener(this) {
@Override
public ShowableListMenu getPopup() {
return popup;
}
@Override
public boolean onForwardingStarted() {
if (!mPopup.isShowing()) {
mPopup.show(getTextDirection(), getTextAlignment());
}
return true;
}
};
break;
}
}
mGravity = a.getInt(R.styleable.Spinner_gravity, Gravity.CENTER);
mDisableChildrenWhenDisabled = a.getBoolean(
R.styleable.Spinner_disableChildrenWhenDisabled, false);
a.recycle();
// Base constructor can call setAdapter before we initialize mPopup.
// Finish setting things up if this happened.
if (mTempAdapter != null) {
setAdapter(mTempAdapter);
mTempAdapter = null;
}
}
/**
* @return the context used to inflate the Spinner's popup or dialog window
*/
public Context getPopupContext() {
return mPopupContext;
}
/**
* Set the background drawable for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; this method is a no-op in other modes.
*
* @param background Background drawable
*
* @attr ref android.R.styleable#Spinner_popupBackground
*/
public void setPopupBackgroundDrawable(Drawable background) {
if (!(mPopup instanceof DropdownPopup)) {
Log.e(TAG, "setPopupBackgroundDrawable: incompatible spinner mode; ignoring...");
return;
}
mPopup.setBackgroundDrawable(background);
}
/**
* Set the background drawable for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; this method is a no-op in other modes.
*
* @param resId Resource ID of a background drawable
*
* @attr ref android.R.styleable#Spinner_popupBackground
*/
public void setPopupBackgroundResource(@DrawableRes int resId) {
setPopupBackgroundDrawable(getPopupContext().getDrawable(resId));
}
/**
* Get the background drawable for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; other modes will return null.
*
* @return background Background drawable
*
* @attr ref android.R.styleable#Spinner_popupBackground
*/
public Drawable getPopupBackground() {
return mPopup.getBackground();
}
/**
* Set a vertical offset in pixels for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; this method is a no-op in other modes.
*
* @param pixels Vertical offset in pixels
*
* @attr ref android.R.styleable#ListPopupWindow_dropDownVerticalOffset
*/
public void setDropDownVerticalOffset(int pixels) {
mPopup.setVerticalOffset(pixels);
}
/**
* Get the configured vertical offset in pixels for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; other modes will return 0.
*
* @return Vertical offset in pixels
*
* @attr ref android.R.styleable#ListPopupWindow_dropDownVerticalOffset
*/
public int getDropDownVerticalOffset() {
return mPopup.getVerticalOffset();
}
/**
* Set a horizontal offset in pixels for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; this method is a no-op in other modes.
*
* @param pixels Horizontal offset in pixels
*
* @attr ref android.R.styleable#ListPopupWindow_dropDownHorizontalOffset
*/
public void setDropDownHorizontalOffset(int pixels) {
mPopup.setHorizontalOffset(pixels);
}
/**
* Get the configured horizontal offset in pixels for the spinner's popup window of choices.
* Only valid in {@link #MODE_DROPDOWN}; other modes will return 0.
*
* @return Horizontal offset in pixels
*
* @attr ref android.R.styleable#ListPopupWindow_dropDownHorizontalOffset
*/
public int getDropDownHorizontalOffset() {
return mPopup.getHorizontalOffset();
}
/**
* Set the width of the spinner's popup window of choices in pixels. This value
* may also be set to {@link android.view.ViewGroup.LayoutParams#MATCH_PARENT}
* to match the width of the Spinner itself, or
* {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} to wrap to the measured size
* of contained dropdown list items.
*
* Only valid in {@link #MODE_DROPDOWN}; this method is a no-op in other modes.
* * @param pixels Width in pixels, WRAP_CONTENT, or MATCH_PARENT * * @attr ref android.R.styleable#Spinner_dropDownWidth */ public void setDropDownWidth(int pixels) { if (!(mPopup instanceof DropdownPopup)) { Log.e(TAG, "Cannot set dropdown width for MODE_DIALOG, ignoring"); return; } mDropDownWidth = pixels; } /** * Get the configured width of the spinner's popup window of choices in pixels. * The returned value may also be {@link android.view.ViewGroup.LayoutParams#MATCH_PARENT} * meaning the popup window will match the width of the Spinner itself, or * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} to wrap to the measured size * of contained dropdown list items. * * @return Width in pixels, WRAP_CONTENT, or MATCH_PARENT * * @attr ref android.R.styleable#Spinner_dropDownWidth */ public int getDropDownWidth() { return mDropDownWidth; } @Override public void setEnabled(boolean enabled) { super.setEnabled(enabled); if (mDisableChildrenWhenDisabled) { final int count = getChildCount(); for (int i = 0; i < count; i++) { getChildAt(i).setEnabled(enabled); } } } /** * Describes how the selected item view is positioned. Currently only the horizontal component * is used. The default is determined by the current theme. * * @param gravity See {@link android.view.Gravity} * * @attr ref android.R.styleable#Spinner_gravity */ public void setGravity(int gravity) { if (mGravity != gravity) { if ((gravity & Gravity.HORIZONTAL_GRAVITY_MASK) == 0) { gravity |= Gravity.START; } mGravity = gravity; requestLayout(); } } /** * Describes how the selected item view is positioned. The default is determined by the * current theme. * * @return A {@link android.view.Gravity Gravity} value */ public int getGravity() { return mGravity; } /** * Sets the {@link SpinnerAdapter} used to provide the data which backs * this Spinner. ** If this Spinner has a popup theme set in XML via the * {@link android.R.styleable#Spinner_popupTheme popupTheme} attribute, the * adapter should inflate drop-down views using the same theme. The easiest * way to achieve this is by using {@link #getPopupContext()} to obtain a * layout inflater for use in * {@link SpinnerAdapter#getDropDownView(int, View, ViewGroup)}. *
* Spinner overrides {@link Adapter#getViewTypeCount()} on the * Adapter associated with this view. Calling * {@link Adapter#getItemViewType(int) getItemViewType(int)} on the object * returned from {@link #getAdapter()} will always return 0. Calling * {@link Adapter#getViewTypeCount() getViewTypeCount()} will always return * 1. On API {@link Build.VERSION_CODES#LOLLIPOP} and above, attempting to set an * adapter with more than one view type will throw an * {@link IllegalArgumentException}. * * @param adapter the adapter to set * * @see AbsSpinner#setAdapter(SpinnerAdapter) * @throws IllegalArgumentException if the adapter has more than one view * type */ @Override public void setAdapter(SpinnerAdapter adapter) { // The super constructor may call setAdapter before we're prepared. // Postpone doing anything until we've finished construction. if (mPopup == null) { mTempAdapter = adapter; return; } super.setAdapter(adapter); mRecycler.clear(); final int targetSdkVersion = mContext.getApplicationInfo().targetSdkVersion; if (targetSdkVersion >= Build.VERSION_CODES.LOLLIPOP && adapter != null && adapter.getViewTypeCount() != 1) { throw new IllegalArgumentException("Spinner adapter view type count must be 1"); } final Context popupContext = mPopupContext == null ? mContext : mPopupContext; mPopup.setAdapter(new DropDownAdapter(adapter, popupContext.getTheme())); } @Override public int getBaseline() { View child = null; if (getChildCount() > 0) { child = getChildAt(0); } else if (mAdapter != null && mAdapter.getCount() > 0) { child = makeView(0, false); mRecycler.put(0, child); } if (child != null) { final int childBaseline = child.getBaseline(); return childBaseline >= 0 ? child.getTop() + childBaseline : -1; } else { return -1; } } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); if (mPopup != null && mPopup.isShowing()) { mPopup.dismiss(); } } /** *
A spinner does not support item click events. Calling this method * will raise an exception.
*Instead use {@link AdapterView#setOnItemSelectedListener}.
*
* @param l this listener will be ignored
*/
@Override
public void setOnItemClickListener(OnItemClickListener l) {
throw new RuntimeException("setOnItemClickListener cannot be used with a spinner.");
}
/**
* @hide internal use only
*/
public void setOnItemClickListenerInt(OnItemClickListener l) {
super.setOnItemClickListener(l);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (mForwardingListener != null && mForwardingListener.onTouch(this, event)) {
return true;
}
return super.onTouchEvent(event);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (mPopup != null && MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.AT_MOST) {
final int measuredWidth = getMeasuredWidth();
setMeasuredDimension(Math.min(Math.max(measuredWidth,
measureContentWidth(getAdapter(), getBackground())),
MeasureSpec.getSize(widthMeasureSpec)),
getMeasuredHeight());
}
}
/**
* @see android.view.View#onLayout(boolean,int,int,int,int)
*
* Creates and positions all views
*
*/
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
mInLayout = true;
layout(0, false);
mInLayout = false;
}
/**
* Creates and positions all views for this Spinner.
*
* @param delta Change in the selected position. +1 means selection is moving to the right,
* so views are scrolling to the left. -1 means selection is moving to the left.
*/
@Override
void layout(int delta, boolean animate) {
int childrenLeft = mSpinnerPadding.left;
int childrenWidth = mRight - mLeft - mSpinnerPadding.left - mSpinnerPadding.right;
if (mDataChanged) {
handleDataChanged();
}
// Handle the empty set by removing all views
if (mItemCount == 0) {
resetList();
return;
}
if (mNextSelectedPosition >= 0) {
setSelectedPositionInt(mNextSelectedPosition);
}
recycleAllViews();
// Clear out old views
removeAllViewsInLayout();
// Make selected view and position it
mFirstPosition = mSelectedPosition;
if (mAdapter != null) {
View sel = makeView(mSelectedPosition, true);
int width = sel.getMeasuredWidth();
int selectedOffset = childrenLeft;
final int layoutDirection = getLayoutDirection();
final int absoluteGravity = Gravity.getAbsoluteGravity(mGravity, layoutDirection);
switch (absoluteGravity & Gravity.HORIZONTAL_GRAVITY_MASK) {
case Gravity.CENTER_HORIZONTAL:
selectedOffset = childrenLeft + (childrenWidth / 2) - (width / 2);
break;
case Gravity.RIGHT:
selectedOffset = childrenLeft + childrenWidth - width;
break;
}
sel.offsetLeftAndRight(selectedOffset);
}
// Flush any cached views that did not get reused above
mRecycler.clear();
invalidate();
checkSelectionChanged();
mDataChanged = false;
mNeedSync = false;
setNextSelectedPositionInt(mSelectedPosition);
}
/**
* Obtain a view, either by pulling an existing view from the recycler or
* by getting a new one from the adapter. If we are animating, make sure
* there is enough information in the view's layout parameters to animate
* from the old to new positions.
*
* @param position Position in the spinner for the view to obtain
* @param addChild true to add the child to the spinner, false to obtain and configure only.
* @return A view for the given position
*/
private View makeView(int position, boolean addChild) {
View child;
if (!mDataChanged) {
child = mRecycler.get(position);
if (child != null) {
// Position the view
setUpChild(child, addChild);
return child;
}
}
// Nothing found in the recycler -- ask the adapter for a view
child = mAdapter.getView(position, null, this);
// Position the view
setUpChild(child, addChild);
return child;
}
/**
* Helper for makeAndAddView to set the position of a view
* and fill out its layout paramters.
*
* @param child The view to position
* @param addChild true if the child should be added to the Spinner during setup
*/
private void setUpChild(View child, boolean addChild) {
// Respect layout params that are already in the view. Otherwise
// make some up...
ViewGroup.LayoutParams lp = child.getLayoutParams();
if (lp == null) {
lp = generateDefaultLayoutParams();
}
addViewInLayout(child, 0, lp);
child.setSelected(hasFocus());
if (mDisableChildrenWhenDisabled) {
child.setEnabled(isEnabled());
}
// Get measure specs
int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec,
mSpinnerPadding.top + mSpinnerPadding.bottom, lp.height);
int childWidthSpec = ViewGroup.getChildMeasureSpec(mWidthMeasureSpec,
mSpinnerPadding.left + mSpinnerPadding.right, lp.width);
// Measure child
child.measure(childWidthSpec, childHeightSpec);
int childLeft;
int childRight;
// Position vertically based on gravity setting
int childTop = mSpinnerPadding.top
+ ((getMeasuredHeight() - mSpinnerPadding.bottom -
mSpinnerPadding.top - child.getMeasuredHeight()) / 2);
int childBottom = childTop + child.getMeasuredHeight();
int width = child.getMeasuredWidth();
childLeft = 0;
childRight = childLeft + width;
child.layout(childLeft, childTop, childRight, childBottom);
if (!addChild) {
removeViewInLayout(child);
}
}
@Override
public boolean performClick() {
boolean handled = super.performClick();
if (!handled) {
handled = true;
if (!mPopup.isShowing()) {
mPopup.show(getTextDirection(), getTextAlignment());
}
}
return handled;
}
public void onClick(DialogInterface dialog, int which) {
setSelection(which);
dialog.dismiss();
}
@Override
public CharSequence getAccessibilityClassName() {
return Spinner.class.getName();
}
/** @hide */
@Override
public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfoInternal(info);
if (mAdapter != null) {
info.setCanOpenPopup(true);
}
}
/**
* Sets the prompt to display when the dialog is shown.
* @param prompt the prompt to set
*/
public void setPrompt(CharSequence prompt) {
mPopup.setPromptText(prompt);
}
/**
* Sets the prompt to display when the dialog is shown.
* @param promptId the resource ID of the prompt to display when the dialog is shown
*/
public void setPromptId(int promptId) {
setPrompt(getContext().getText(promptId));
}
/**
* @return The prompt to display when the dialog is shown
*/
public CharSequence getPrompt() {
return mPopup.getHintText();
}
int measureContentWidth(SpinnerAdapter adapter, Drawable background) {
if (adapter == null) {
return 0;
}
int width = 0;
View itemView = null;
int itemType = 0;
final int widthMeasureSpec =
MeasureSpec.makeSafeMeasureSpec(getMeasuredWidth(), MeasureSpec.UNSPECIFIED);
final int heightMeasureSpec =
MeasureSpec.makeSafeMeasureSpec(getMeasuredHeight(), MeasureSpec.UNSPECIFIED);
// Make sure the number of items we'll measure is capped. If it's a huge data set
// with wildly varying sizes, oh well.
int start = Math.max(0, getSelectedItemPosition());
final int end = Math.min(adapter.getCount(), start + MAX_ITEMS_MEASURED);
final int count = end - start;
start = Math.max(0, start - (MAX_ITEMS_MEASURED - count));
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, this);
if (itemView.getLayoutParams() == null) {
itemView.setLayoutParams(new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT));
}
itemView.measure(widthMeasureSpec, heightMeasureSpec);
width = Math.max(width, itemView.getMeasuredWidth());
}
// Add background padding to measured width
if (background != null) {
background.getPadding(mTempRect);
width += mTempRect.left + mTempRect.right;
}
return width;
}
@Override
public Parcelable onSaveInstanceState() {
final SavedState ss = new SavedState(super.onSaveInstanceState());
ss.showDropdown = mPopup != null && mPopup.isShowing();
return ss;
}
@Override
public void onRestoreInstanceState(Parcelable state) {
SavedState ss = (SavedState) state;
super.onRestoreInstanceState(ss.getSuperState());
if (ss.showDropdown) {
ViewTreeObserver vto = getViewTreeObserver();
if (vto != null) {
final OnGlobalLayoutListener listener = new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
if (!mPopup.isShowing()) {
mPopup.show(getTextDirection(), getTextAlignment());
}
final ViewTreeObserver vto = getViewTreeObserver();
if (vto != null) {
vto.removeOnGlobalLayoutListener(this);
}
}
};
vto.addOnGlobalLayoutListener(listener);
}
}
}
static class SavedState extends AbsSpinner.SavedState {
boolean showDropdown;
SavedState(Parcelable superState) {
super(superState);
}
private SavedState(Parcel in) {
super(in);
showDropdown = in.readByte() != 0;
}
@Override
public void writeToParcel(Parcel out, int flags) {
super.writeToParcel(out, flags);
out.writeByte((byte) (showDropdown ? 1 : 0));
}
public static final Parcelable.Creator Wrapper class for an Adapter. Transforms the embedded Adapter instance
* into a ListAdapter.