/* * Copyright (C) 2006 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.view; import android.content.ClipData; import android.content.Context; import android.content.res.Configuration; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.Bitmap; import android.graphics.Camera; import android.graphics.Canvas; import android.graphics.Insets; import android.graphics.Interpolator; import android.graphics.LinearGradient; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.PixelFormat; import android.graphics.Point; import android.graphics.PorterDuff; import android.graphics.PorterDuffXfermode; import android.graphics.Rect; import android.graphics.RectF; import android.graphics.Region; import android.graphics.Shader; import android.graphics.drawable.ColorDrawable; import android.graphics.drawable.Drawable; import android.hardware.display.DisplayManagerGlobal; import android.os.Build; import android.os.Bundle; import android.os.Handler; import android.os.IBinder; import android.os.Parcel; import android.os.Parcelable; import android.os.RemoteException; import android.os.SystemClock; import android.os.SystemProperties; import android.text.TextUtils; import android.util.AttributeSet; import android.util.FloatProperty; import android.util.Log; import android.util.Pools.SynchronizedPool; import android.util.Property; import android.util.SparseArray; import android.util.TypedValue; import android.view.ContextMenu.ContextMenuInfo; import android.view.AccessibilityIterators.TextSegmentIterator; import android.view.AccessibilityIterators.CharacterTextSegmentIterator; import android.view.AccessibilityIterators.WordTextSegmentIterator; import android.view.AccessibilityIterators.ParagraphTextSegmentIterator; import android.view.accessibility.AccessibilityEvent; import android.view.accessibility.AccessibilityEventSource; import android.view.accessibility.AccessibilityManager; import android.view.accessibility.AccessibilityNodeInfo; import android.view.accessibility.AccessibilityNodeProvider; import android.view.animation.Animation; import android.view.animation.AnimationUtils; import android.view.animation.Transformation; import android.view.inputmethod.EditorInfo; import android.view.inputmethod.InputConnection; import android.view.inputmethod.InputMethodManager; import android.widget.ScrollBarDrawable; import static android.os.Build.VERSION_CODES.*; import static java.lang.Math.max; import com.android.internal.R; import com.android.internal.util.Predicate; import com.android.internal.view.menu.MenuBuilder; import com.google.android.collect.Lists; import com.google.android.collect.Maps; import java.lang.ref.WeakReference; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.HashMap; import java.util.Locale; import java.util.concurrent.CopyOnWriteArrayList; import java.util.concurrent.atomic.AtomicInteger; /** *

* This class represents the basic building block for user interface components. A View * occupies a rectangular area on the screen and is responsible for drawing and * event handling. View is the base class for widgets, which are * used to create interactive UI components (buttons, text fields, etc.). The * {@link android.view.ViewGroup} subclass is the base class for layouts, which * are invisible containers that hold other Views (or other ViewGroups) and define * their layout properties. *

* *

Developer Guides

For information about using this class to develop your application's user interface, * read the User Interface developer guide. *

* * *

Using Views

* All of the views in a window are arranged in a single tree. You can add views * either from code or by specifying a tree of views in one or more XML layout * files. There are many specialized subclasses of views that act as controls or * are capable of displaying text, images, or other content. *

* Once you have created a tree of views, there are typically a few types of * common operations you may wish to perform: *

Set properties: for example setting the text of a * {@link android.widget.TextView}. The available properties and the methods * that set them will vary among the different subclasses of views. Note that * properties that are known at build time can be set in the XML layout * files.
Set focus: The framework will handled moving focus in * response to user input. To force focus to a specific view, call * {@link #requestFocus}.
Set up listeners: Views allow clients to set listeners * that will be notified when something interesting happens to the view. For * example, all views will let you set a listener to be notified when the view * gains or loses focus. You can register such a listener using * {@link #setOnFocusChangeListener(android.view.View.OnFocusChangeListener)}. * Other view subclasses offer more specialized listeners. For example, a Button * exposes a listener to notify clients when the button is clicked.
Set visibility: You can hide or show views using * {@link #setVisibility(int)}.

* Note: The Android framework is responsible for measuring, laying out and * drawing views. You should not call methods that perform these actions on * views yourself unless you are actually implementing a * {@link android.view.ViewGroup}. *

* * *

Implementing a Custom View

* *

* To implement a custom view, you will usually begin by providing overrides for * some of the standard methods that the framework calls on all views. You do * not need to override all of these methods. In fact, you can start by just * overriding {@link #onDraw(android.graphics.Canvas)}. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Category Methods Description
Creation Constructors There is a form of the constructor that are called when the view * is created from code and a form that is called when the view is * inflated from a layout file. The second form should parse and apply * any attributes defined in the layout file. *
{@link #onFinishInflate()} Called after a view and all of its children has been inflated * from XML.
Layout {@link #onMeasure(int, int)} Called to determine the size requirements for this view and all * of its children. *
{@link #onLayout(boolean, int, int, int, int)} Called when this view should assign a size and position to all * of its children. *
{@link #onSizeChanged(int, int, int, int)} Called when the size of this view has changed. *
Drawing {@link #onDraw(android.graphics.Canvas)} Called when the view should render its content. *
Event processing {@link #onKeyDown(int, KeyEvent)} Called when a new hardware key event occurs. *
{@link #onKeyUp(int, KeyEvent)} Called when a hardware key up event occurs. *
{@link #onTrackballEvent(MotionEvent)} Called when a trackball motion event occurs. *
{@link #onTouchEvent(MotionEvent)} Called when a touch screen motion event occurs. *
Focus {@link #onFocusChanged(boolean, int, android.graphics.Rect)} Called when the view gains or loses focus. *
{@link #onWindowFocusChanged(boolean)} Called when the window containing the view gains or loses focus. *
Attaching {@link #onAttachedToWindow()} Called when the view is attached to a window. *
{@link #onDetachedFromWindow} Called when the view is detached from its window. *
{@link #onWindowVisibilityChanged(int)} Called when the visibility of the window containing the view * has changed. *
*

Category	Methods	Description
Creation	Constructors	There is a form of the constructor that are called when the view * is created from code and a form that is called when the view is * inflated from a layout file. The second form should parse and apply * any attributes defined in the layout file. *
`{@link #onFinishInflate()}`	Called after a view and all of its children has been inflated * from XML.
Layout	`{@link #onMeasure(int, int)}`	Called to determine the size requirements for this view and all * of its children. *
`{@link #onLayout(boolean, int, int, int, int)}`	Called when this view should assign a size and position to all * of its children. *
`{@link #onSizeChanged(int, int, int, int)}`	Called when the size of this view has changed. *
Drawing	`{@link #onDraw(android.graphics.Canvas)}`	Called when the view should render its content. *
Event processing	`{@link #onKeyDown(int, KeyEvent)}`	Called when a new hardware key event occurs. *
`{@link #onKeyUp(int, KeyEvent)}`	Called when a hardware key up event occurs. *
`{@link #onTrackballEvent(MotionEvent)}`	Called when a trackball motion event occurs. *
`{@link #onTouchEvent(MotionEvent)}`	Called when a touch screen motion event occurs. *
Focus	`{@link #onFocusChanged(boolean, int, android.graphics.Rect)}`	Called when the view gains or loses focus. *
`{@link #onWindowFocusChanged(boolean)}`	Called when the window containing the view gains or loses focus. *
Attaching	`{@link #onAttachedToWindow()}`	Called when the view is attached to a window. *
`{@link #onDetachedFromWindow}`	Called when the view is detached from its window. *
`{@link #onWindowVisibilityChanged(int)}`	Called when the visibility of the window containing the view * has changed. *

* * *

IDs

* Views may have an integer id associated with them. These ids are typically * assigned in the layout XML files, and are used to find specific views within * the view tree. A common pattern is to: *

Define a Button in the layout file and assign it a unique ID. *

 * <Button
 *     android:id="@+id/my_button"
 *     android:layout_width="wrap_content"
 *     android:layout_height="wrap_content"
 *     android:text="@string/my_button_text"/>
 *

From the onCreate method of an Activity, find the Button *

 *      Button myButton = (Button) findViewById(R.id.my_button);
 *

* View IDs need not be unique throughout the tree, but it is good practice to * ensure that they are at least unique within the part of the tree you are * searching. *

* * *

Position

* The geometry of a view is that of a rectangle. A view has a location, * expressed as a pair of left and top coordinates, and * two dimensions, expressed as a width and a height. The unit for location * and dimensions is the pixel. *

* *

* It is possible to retrieve the location of a view by invoking the methods * {@link #getLeft()} and {@link #getTop()}. The former returns the left, or X, * coordinate of the rectangle representing the view. The latter returns the * top, or Y, coordinate of the rectangle representing the view. These methods * both return the location of the view relative to its parent. For instance, * when getLeft() returns 20, that means the view is located 20 pixels to the * right of the left edge of its direct parent. *

* *

* In addition, several convenience methods are offered to avoid unnecessary * computations, namely {@link #getRight()} and {@link #getBottom()}. * These methods return the coordinates of the right and bottom edges of the * rectangle representing the view. For instance, calling {@link #getRight()} * is similar to the following computation: getLeft() + getWidth() * (see Size for more information about the width.) *

* * *

Size, padding and margins

* The size of a view is expressed with a width and a height. A view actually * possess two pairs of width and height values. *

* *

* The first pair is known as measured width and * measured height. These dimensions define how big a view wants to be * within its parent (see Layout for more details.) The * measured dimensions can be obtained by calling {@link #getMeasuredWidth()} * and {@link #getMeasuredHeight()}. *

* *

* The second pair is simply known as width and height, or * sometimes drawing width and drawing height. These * dimensions define the actual size of the view on screen, at drawing time and * after layout. These values may, but do not have to, be different from the * measured width and height. The width and height can be obtained by calling * {@link #getWidth()} and {@link #getHeight()}. *

* *

* To measure its dimensions, a view takes into account its padding. The padding * is expressed in pixels for the left, top, right and bottom parts of the view. * Padding can be used to offset the content of the view by a specific amount of * pixels. For instance, a left padding of 2 will push the view's content by * 2 pixels to the right of the left edge. Padding can be set using the * {@link #setPadding(int, int, int, int)} or {@link #setPaddingRelative(int, int, int, int)} * method and queried by calling {@link #getPaddingLeft()}, {@link #getPaddingTop()}, * {@link #getPaddingRight()}, {@link #getPaddingBottom()}, {@link #getPaddingStart()}, * {@link #getPaddingEnd()}. *

* *

* Even though a view can define a padding, it does not provide any support for * margins. However, view groups provide such a support. Refer to * {@link android.view.ViewGroup} and * {@link android.view.ViewGroup.MarginLayoutParams} for further information. *

* * *

Layout

* Layout is a two pass process: a measure pass and a layout pass. The measuring * pass is implemented in {@link #measure(int, int)} and is a top-down traversal * of the view tree. Each view pushes dimension specifications down the tree * during the recursion. At the end of the measure pass, every view has stored * its measurements. The second pass happens in * {@link #layout(int,int,int,int)} and is also top-down. During * this pass each parent is responsible for positioning all of its children * using the sizes computed in the measure pass. *

* *

* When a view's measure() method returns, its {@link #getMeasuredWidth()} and * {@link #getMeasuredHeight()} values must be set, along with those for all of * that view's descendants. A view's measured width and measured height values * must respect the constraints imposed by the view's parents. This guarantees * that at the end of the measure pass, all parents accept all of their * children's measurements. A parent view may call measure() more than once on * its children. For example, the parent may measure each child once with * unspecified dimensions to find out how big they want to be, then call * measure() on them again with actual numbers if the sum of all the children's * unconstrained sizes is too big or too small. *

* *

* The measure pass uses two classes to communicate dimensions. The * {@link MeasureSpec} class is used by views to tell their parents how they * want to be measured and positioned. The base LayoutParams class just * describes how big the view wants to be for both width and height. For each * dimension, it can specify one of: *

an exact number *
MATCH_PARENT, which means the view wants to be as big as its parent * (minus padding) *
WRAP_CONTENT, which means that the view wants to be just big enough to * enclose its content (plus padding). *

* There are subclasses of LayoutParams for different subclasses of ViewGroup. * For example, AbsoluteLayout has its own subclass of LayoutParams which adds * an X and Y value. *

* *

* MeasureSpecs are used to push requirements down the tree from parent to * child. A MeasureSpec can be in one of three modes: *

UNSPECIFIED: This is used by a parent to determine the desired dimension * of a child view. For example, a LinearLayout may call measure() on its child * with the height set to UNSPECIFIED and a width of EXACTLY 240 to find out how * tall the child view wants to be given a width of 240 pixels. *
EXACTLY: This is used by the parent to impose an exact size on the * child. The child must use this size, and guarantee that all of its * descendants will fit within this size. *
AT_MOST: This is used by the parent to impose a maximum size on the * child. The child must gurantee that it and all of its descendants will fit * within this size. *

* *

* To intiate a layout, call {@link #requestLayout}. This method is typically * called by a view on itself when it believes that is can no longer fit within * its current bounds. *

* * *

Drawing

* Drawing is handled by walking the tree and rendering each view that * intersects the invalid region. Because the tree is traversed in-order, * this means that parents will draw before (i.e., behind) their children, with * siblings drawn in the order they appear in the tree. * If you set a background drawable for a View, then the View will draw it for you * before calling back to its onDraw() method. *

* *

* Note that the framework will not draw views that are not in the invalid region. *

* *

* To force a view to draw, call {@link #invalidate()}. *

* * *

Event Handling and Threading

* The basic cycle of a view is as follows: *

An event comes in and is dispatched to the appropriate view. The view * handles the event and notifies any listeners.
If in the course of processing the event, the view's bounds may need * to be changed, the view will call {@link #requestLayout()}.
Similarly, if in the course of processing the event the view's appearance * may need to be changed, the view will call {@link #invalidate()}.
If either {@link #requestLayout()} or {@link #invalidate()} were called, * the framework will take care of measuring, laying out, and drawing the tree * as appropriate.

* *

Note: The entire view tree is single threaded. You must always be on * the UI thread when calling any method on any view. * If you are doing work on other threads and want to update the state of a view * from that thread, you should use a {@link Handler}. *

* * *

Focus Handling

* The framework will handle routine focus movement in response to user input. * This includes changing the focus as views are removed or hidden, or as new * views become available. Views indicate their willingness to take focus * through the {@link #isFocusable} method. To change whether a view can take * focus, call {@link #setFocusable(boolean)}. When in touch mode (see notes below) * views indicate whether they still would like focus via {@link #isFocusableInTouchMode} * and can change this via {@link #setFocusableInTouchMode(boolean)}. *

* Focus movement is based on an algorithm which finds the nearest neighbor in a * given direction. In rare cases, the default algorithm may not match the * intended behavior of the developer. In these situations, you can provide * explicit overrides by using these XML attributes in the layout file: *

 * nextFocusDown
 * nextFocusLeft
 * nextFocusRight
 * nextFocusUp
 *

* * *

* To get a particular view to take focus, call {@link #requestFocus()}. *

* * *

Touch Mode

* When a user is navigating a user interface via directional keys such as a D-pad, it is * necessary to give focus to actionable items such as buttons so the user can see * what will take input. If the device has touch capabilities, however, and the user * begins interacting with the interface by touching it, it is no longer necessary to * always highlight, or give focus to, a particular view. This motivates a mode * for interaction named 'touch mode'. *

* For a touch capable device, once the user touches the screen, the device * will enter touch mode. From this point onward, only views for which * {@link #isFocusableInTouchMode} is true will be focusable, such as text editing widgets. * Other views that are touchable, like buttons, will not take focus when touched; they will * only fire the on click listeners. *

* Any time a user hits a directional key, such as a D-pad direction, the view device will * exit touch mode, and find a view to take focus, so that the user may resume interacting * with the user interface without touching the screen again. *

* The touch mode state is maintained across {@link android.app.Activity}s. Call * {@link #isInTouchMode} to see whether the device is currently in touch mode. *

* * *

Scrolling

* The framework provides basic support for views that wish to internally * scroll their content. This includes keeping track of the X and Y scroll * offset as well as mechanisms for drawing scrollbars. See * {@link #scrollBy(int, int)}, {@link #scrollTo(int, int)}, and * {@link #awakenScrollBars()} for more details. *

* * *

Properties

* The View class exposes an {@link #ALPHA} property, as well as several transform-related * properties, such as {@link #TRANSLATION_X} and {@link #TRANSLATION_Y}. These properties are * available both in the {@link Property} form as well as in similarly-named setter/getter * methods (such as {@link #setAlpha(float)} for {@link #ALPHA}). These properties can * be used to set persistent state associated with these rendering-related properties on the view. * The properties and methods can also be used in conjunction with * {@link android.animation.Animator Animator}-based animations, described more in the * Animation section. *

* * *

Animation

* Starting with Android 3.0, the preferred way of animating views is to use the * {@link android.animation} package APIs. These {@link android.animation.Animator Animator}-based * classes change actual properties of the View object, such as {@link #setAlpha(float) alpha} and * {@link #setTranslationX(float) translationX}. This behavior is contrasted to that of the pre-3.0 * {@link android.view.animation.Animation Animation}-based classes, which instead animate only * how the view is drawn on the display. In particular, the {@link ViewPropertyAnimator} class * makes animating these View properties particularly easy and efficient. *

* Alternatively, you can use the pre-3.0 animation classes to animate how Views are rendered. * You can attach an {@link Animation} object to a view using * {@link #setAnimation(Animation)} or * {@link #startAnimation(Animation)}. The animation can alter the scale, * rotation, translation and alpha of a view over time. If the animation is * attached to a view that has children, the animation will affect the entire * subtree rooted by that node. When an animation is started, the framework will * take care of redrawing the appropriate views until the animation completes. *

* * *

Security

* Sometimes it is essential that an application be able to verify that an action * is being performed with the full knowledge and consent of the user, such as * granting a permission request, making a purchase or clicking on an advertisement. * Unfortunately, a malicious application could try to spoof the user into * performing these actions, unaware, by concealing the intended purpose of the view. * As a remedy, the framework offers a touch filtering mechanism that can be used to * improve the security of views that provide access to sensitive functionality. *

* To enable touch filtering, call {@link #setFilterTouchesWhenObscured(boolean)} or set the * android:filterTouchesWhenObscured layout attribute to true. When enabled, the framework * will discard touches that are received whenever the view's window is obscured by * another visible window. As a result, the view will not receive touches whenever a * toast, dialog or other window appears above the view's window. *

* For more fine-grained control over security, consider overriding the * {@link #onFilterTouchEventForSecurity(MotionEvent)} method to implement your own * security policy. See also {@link MotionEvent#FLAG_WINDOW_IS_OBSCURED}. *

* * @attr ref android.R.styleable#View_alpha * @attr ref android.R.styleable#View_background * @attr ref android.R.styleable#View_clickable * @attr ref android.R.styleable#View_contentDescription * @attr ref android.R.styleable#View_drawingCacheQuality * @attr ref android.R.styleable#View_duplicateParentState * @attr ref android.R.styleable#View_id * @attr ref android.R.styleable#View_requiresFadingEdge * @attr ref android.R.styleable#View_fadeScrollbars * @attr ref android.R.styleable#View_fadingEdgeLength * @attr ref android.R.styleable#View_filterTouchesWhenObscured * @attr ref android.R.styleable#View_fitsSystemWindows * @attr ref android.R.styleable#View_isScrollContainer * @attr ref android.R.styleable#View_focusable * @attr ref android.R.styleable#View_focusableInTouchMode * @attr ref android.R.styleable#View_hapticFeedbackEnabled * @attr ref android.R.styleable#View_keepScreenOn * @attr ref android.R.styleable#View_layerType * @attr ref android.R.styleable#View_layoutDirection * @attr ref android.R.styleable#View_longClickable * @attr ref android.R.styleable#View_minHeight * @attr ref android.R.styleable#View_minWidth * @attr ref android.R.styleable#View_nextFocusDown * @attr ref android.R.styleable#View_nextFocusLeft * @attr ref android.R.styleable#View_nextFocusRight * @attr ref android.R.styleable#View_nextFocusUp * @attr ref android.R.styleable#View_onClick * @attr ref android.R.styleable#View_padding * @attr ref android.R.styleable#View_paddingBottom * @attr ref android.R.styleable#View_paddingLeft * @attr ref android.R.styleable#View_paddingRight * @attr ref android.R.styleable#View_paddingTop * @attr ref android.R.styleable#View_paddingStart * @attr ref android.R.styleable#View_paddingEnd * @attr ref android.R.styleable#View_saveEnabled * @attr ref android.R.styleable#View_rotation * @attr ref android.R.styleable#View_rotationX * @attr ref android.R.styleable#View_rotationY * @attr ref android.R.styleable#View_scaleX * @attr ref android.R.styleable#View_scaleY * @attr ref android.R.styleable#View_scrollX * @attr ref android.R.styleable#View_scrollY * @attr ref android.R.styleable#View_scrollbarSize * @attr ref android.R.styleable#View_scrollbarStyle * @attr ref android.R.styleable#View_scrollbars * @attr ref android.R.styleable#View_scrollbarDefaultDelayBeforeFade * @attr ref android.R.styleable#View_scrollbarFadeDuration * @attr ref android.R.styleable#View_scrollbarTrackHorizontal * @attr ref android.R.styleable#View_scrollbarThumbHorizontal * @attr ref android.R.styleable#View_scrollbarThumbVertical * @attr ref android.R.styleable#View_scrollbarTrackVertical * @attr ref android.R.styleable#View_scrollbarAlwaysDrawHorizontalTrack * @attr ref android.R.styleable#View_scrollbarAlwaysDrawVerticalTrack * @attr ref android.R.styleable#View_soundEffectsEnabled * @attr ref android.R.styleable#View_tag * @attr ref android.R.styleable#View_textAlignment * @attr ref android.R.styleable#View_textDirection * @attr ref android.R.styleable#View_transformPivotX * @attr ref android.R.styleable#View_transformPivotY * @attr ref android.R.styleable#View_translationX * @attr ref android.R.styleable#View_translationY * @attr ref android.R.styleable#View_visibility * * @see android.view.ViewGroup */ public class View implements Drawable.Callback, KeyEvent.Callback, AccessibilityEventSource { private static final boolean DBG = false; /** * The logging tag used by this class with android.util.Log. */ protected static final String VIEW_LOG_TAG = "View"; /** * When set to true, apps will draw debugging information about their layouts. * * @hide */ public static final String DEBUG_LAYOUT_PROPERTY = "debug.layout"; /** * Used to mark a View that has no ID. */ public static final int NO_ID = -1; private static boolean sUseBrokenMakeMeasureSpec = false; /** * This view does not want keystrokes. Use with TAKES_FOCUS_MASK when * calling setFlags. */ private static final int NOT_FOCUSABLE = 0x00000000; /** * This view wants keystrokes. Use with TAKES_FOCUS_MASK when calling * setFlags. */ private static final int FOCUSABLE = 0x00000001; /** * Mask for use with setFlags indicating bits used for focus. */ private static final int FOCUSABLE_MASK = 0x00000001; /** * This view will adjust its padding to fit sytem windows (e.g. status bar) */ private static final int FITS_SYSTEM_WINDOWS = 0x00000002; /** * This view is visible. * Use with {@link #setVisibility} and {@code * android:visibility}. */ public static final int VISIBLE = 0x00000000; /** * This view is invisible, but it still takes up space for layout purposes. * Use with {@link #setVisibility} and {@code * android:visibility}. */ public static final int INVISIBLE = 0x00000004; /** * This view is invisible, and it doesn't take any space for layout * purposes. Use with {@link #setVisibility} and {@code * android:visibility}. */ public static final int GONE = 0x00000008; /** * Mask for use with setFlags indicating bits used for visibility. * {@hide} */ static final int VISIBILITY_MASK = 0x0000000C; private static final int[] VISIBILITY_FLAGS = {VISIBLE, INVISIBLE, GONE}; /** * This view is enabled. Interpretation varies by subclass. * Use with ENABLED_MASK when calling setFlags. * {@hide} */ static final int ENABLED = 0x00000000; /** * This view is disabled. Interpretation varies by subclass. * Use with ENABLED_MASK when calling setFlags. * {@hide} */ static final int DISABLED = 0x00000020; /** * Mask for use with setFlags indicating bits used for indicating whether * this view is enabled * {@hide} */ static final int ENABLED_MASK = 0x00000020; /** * This view won't draw. {@link #onDraw(android.graphics.Canvas)} won't be * called and further optimizations will be performed. It is okay to have * this flag set and a background. Use with DRAW_MASK when calling setFlags. * {@hide} */ static final int WILL_NOT_DRAW = 0x00000080; /** * Mask for use with setFlags indicating bits used for indicating whether * this view is will draw * {@hide} */ static final int DRAW_MASK = 0x00000080; /** *

This view doesn't show scrollbars.

* {@hide} */ static final int SCROLLBARS_NONE = 0x00000000; /** *

This view shows horizontal scrollbars.

* {@hide} */ static final int SCROLLBARS_HORIZONTAL = 0x00000100; /** *

This view shows vertical scrollbars.

* {@hide} */ static final int SCROLLBARS_VERTICAL = 0x00000200; /** *

Mask for use with setFlags indicating bits used for indicating which * scrollbars are enabled.

* {@hide} */ static final int SCROLLBARS_MASK = 0x00000300; /** * Indicates that the view should filter touches when its window is obscured. * Refer to the class comments for more information about this security feature. * {@hide} */ static final int FILTER_TOUCHES_WHEN_OBSCURED = 0x00000400; /** * Set for framework elements that use FITS_SYSTEM_WINDOWS, to indicate * that they are optional and should be skipped if the window has * requested system UI flags that ignore those insets for layout. */ static final int OPTIONAL_FITS_SYSTEM_WINDOWS = 0x00000800; /** *

This view doesn't show fading edges.

* {@hide} */ static final int FADING_EDGE_NONE = 0x00000000; /** *

This view shows horizontal fading edges.

* {@hide} */ static final int FADING_EDGE_HORIZONTAL = 0x00001000; /** *

This view shows vertical fading edges.

* {@hide} */ static final int FADING_EDGE_VERTICAL = 0x00002000; /** *

Mask for use with setFlags indicating bits used for indicating which * fading edges are enabled.

* {@hide} */ static final int FADING_EDGE_MASK = 0x00003000; /** *

Indicates this view can be clicked. When clickable, a View reacts * to clicks by notifying the OnClickListener.

* {@hide} */ static final int CLICKABLE = 0x00004000; /** *

Indicates this view is caching its drawing into a bitmap.

* {@hide} */ static final int DRAWING_CACHE_ENABLED = 0x00008000; /** *

Indicates that no icicle should be saved for this view.

* {@hide} */ static final int SAVE_DISABLED = 0x000010000; /** *

Mask for use with setFlags indicating bits used for the saveEnabled * property.

* {@hide} */ static final int SAVE_DISABLED_MASK = 0x000010000; /** *

Indicates that no drawing cache should ever be created for this view.

* {@hide} */ static final int WILL_NOT_CACHE_DRAWING = 0x000020000; /** *

Indicates this view can take / keep focus when int touch mode.

* {@hide} */ static final int FOCUSABLE_IN_TOUCH_MODE = 0x00040000; /** *

Enables low quality mode for the drawing cache.

*/ public static final int DRAWING_CACHE_QUALITY_LOW = 0x00080000; /** *

Enables high quality mode for the drawing cache.

*/ public static final int DRAWING_CACHE_QUALITY_HIGH = 0x00100000; /** *

Enables automatic quality mode for the drawing cache.

*/ public static final int DRAWING_CACHE_QUALITY_AUTO = 0x00000000; private static final int[] DRAWING_CACHE_QUALITY_FLAGS = { DRAWING_CACHE_QUALITY_AUTO, DRAWING_CACHE_QUALITY_LOW, DRAWING_CACHE_QUALITY_HIGH }; /** *

Mask for use with setFlags indicating bits used for the cache * quality property.

* {@hide} */ static final int DRAWING_CACHE_QUALITY_MASK = 0x00180000; /** *

* Indicates this view can be long clicked. When long clickable, a View * reacts to long clicks by notifying the OnLongClickListener or showing a * context menu. *

* {@hide} */ static final int LONG_CLICKABLE = 0x00200000; /** *

Indicates that this view gets its drawable states from its direct parent * and ignores its original internal states.

* * @hide */ static final int DUPLICATE_PARENT_STATE = 0x00400000; /** * The scrollbar style to display the scrollbars inside the content area, * without increasing the padding. The scrollbars will be overlaid with * translucency on the view's content. */ public static final int SCROLLBARS_INSIDE_OVERLAY = 0; /** * The scrollbar style to display the scrollbars inside the padded area, * increasing the padding of the view. The scrollbars will not overlap the * content area of the view. */ public static final int SCROLLBARS_INSIDE_INSET = 0x01000000; /** * The scrollbar style to display the scrollbars at the edge of the view, * without increasing the padding. The scrollbars will be overlaid with * translucency. */ public static final int SCROLLBARS_OUTSIDE_OVERLAY = 0x02000000; /** * The scrollbar style to display the scrollbars at the edge of the view, * increasing the padding of the view. The scrollbars will only overlap the * background, if any. */ public static final int SCROLLBARS_OUTSIDE_INSET = 0x03000000; /** * Mask to check if the scrollbar style is overlay or inset. * {@hide} */ static final int SCROLLBARS_INSET_MASK = 0x01000000; /** * Mask to check if the scrollbar style is inside or outside. * {@hide} */ static final int SCROLLBARS_OUTSIDE_MASK = 0x02000000; /** * Mask for scrollbar style. * {@hide} */ static final int SCROLLBARS_STYLE_MASK = 0x03000000; /** * View flag indicating that the screen should remain on while the * window containing this view is visible to the user. This effectively * takes care of automatically setting the WindowManager's * {@link WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON}. */ public static final int KEEP_SCREEN_ON = 0x04000000; /** * View flag indicating whether this view should have sound effects enabled * for events such as clicking and touching. */ public static final int SOUND_EFFECTS_ENABLED = 0x08000000; /** * View flag indicating whether this view should have haptic feedback * enabled for events such as long presses. */ public static final int HAPTIC_FEEDBACK_ENABLED = 0x10000000; /** *

Indicates that the view hierarchy should stop saving state when * it reaches this view. If state saving is initiated immediately at * the view, it will be allowed. * {@hide} */ static final int PARENT_SAVE_DISABLED = 0x20000000; /** *

Mask for use with setFlags indicating bits used for PARENT_SAVE_DISABLED.

Developer Guides

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