LevelListDrawable

Class Overview

A resource that manages a number of alternate Drawables, each assigned a maximum numerical value. Setting the level value of the object with setLevel(int) will load the image with the next greater or equal value assigned to its max attribute. A good example use of a LevelListDrawable would be a battery level indicator icon, with different images to indicate the current battery level.

It can be defined in an XML file with the <level-list> element. Each Drawable level is defined in a nested <item>. For example:

 <level-list xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:maxLevel="0" android:drawable="@drawable/ic_wifi_signal_1" />
  <item android:maxLevel="1" android:drawable="@drawable/ic_wifi_signal_2" />
  <item android:maxLevel="2" android:drawable="@drawable/ic_wifi_signal_3" />
  <item android:maxLevel="3" android:drawable="@drawable/ic_wifi_signal_4" />
 </level-list>

With this XML saved into the res/drawable/ folder of the project, it can be referenced as the drawable for an ImageView. The default image is the first in the list. It can then be changed to one of the other levels with setImageLevel(int). For more information, see the guide to Drawable Resources.

Summary

[Expand] Inherited Methods
From class android.graphics.drawable.DrawableContainer void draw(Canvas canvas) Draw in its bounds (set via setBounds) respecting optional effects such as alpha (set via setAlpha) and color filter (set via setColorFilter). int getChangingConfigurations() Return a mask of the configuration parameters for which this drawable may change, requiring that it be re-created. Drawable.ConstantState getConstantState() Return a Drawable.ConstantState instance that holds the shared state of this Drawable. Drawable getCurrent() int getIntrinsicHeight() Return the intrinsic height of the underlying drawable object. int getIntrinsicWidth() Return the intrinsic width of the underlying drawable object. int getMinimumHeight() Returns the minimum height suggested by this Drawable. int getMinimumWidth() Returns the minimum width suggested by this Drawable. int getOpacity() Return the opacity/transparency of this Drawable. boolean getPadding(Rect padding) Return in padding the insets suggested by this Drawable for placing content inside the drawable's bounds. void invalidateDrawable(Drawable who) Called when the drawable needs to be redrawn. boolean isStateful() Indicates whether this view will change its appearance based on state. void jumpToCurrentState() If this Drawable does transition animations between states, ask that it immediately jump to the current state and skip any active animations. Drawable mutate() Make this drawable mutable. void onBoundsChange(Rect bounds) Override this in your subclass to change appearance if you recognize the specified state. boolean onLevelChange(int level) Override this in your subclass to change appearance if you vary based on level. boolean onStateChange(int[] state) Override this in your subclass to change appearance if you recognize the specified state. void scheduleDrawable(Drawable who, Runnable what, long when) A Drawable can call this to schedule the next frame of its animation. boolean selectDrawable(int idx) void setAlpha(int alpha) Specify an alpha value for the drawable. void setColorFilter(ColorFilter cf) Specify an optional colorFilter for the drawable. void setConstantState(DrawableContainer.DrawableContainerState state) void setDither(boolean dither) Set to true to have the drawable dither its colors when drawn to a device with fewer than 8-bits per color component. void setEnterFadeDuration(int ms) Change the global fade duration when a new drawable is entering the scene. void setExitFadeDuration(int ms) Change the global fade duration when a new drawable is leaving the scene. boolean setVisible(boolean visible, boolean restart) Set whether this Drawable is visible. void unscheduleDrawable(Drawable who, Runnable what) A Drawable can call this to unschedule an action previously scheduled with scheduleDrawable(Drawable, Runnable, long).
From class android.graphics.drawable.Drawable void clearColorFilter() final Rect copyBounds() Return a copy of the drawable's bounds in a new Rect. final void copyBounds(Rect bounds) Return a copy of the drawable's bounds in the specified Rect (allocated by the caller). static Drawable createFromPath(String pathName) Create a drawable from file path name. static Drawable createFromResourceStream(Resources res, TypedValue value, InputStream is, String srcName, BitmapFactory.Options opts) Create a drawable from an inputstream, using the given resources and value to determine density information. static Drawable createFromResourceStream(Resources res, TypedValue value, InputStream is, String srcName) Create a drawable from an inputstream, using the given resources and value to determine density information. static Drawable createFromStream(InputStream is, String srcName) Create a drawable from an inputstream static Drawable createFromXml(Resources r, XmlPullParser parser) Create a drawable from an XML document. static Drawable createFromXmlInner(Resources r, XmlPullParser parser, AttributeSet attrs) Create from inside an XML document. abstract void draw(Canvas canvas) Draw in its bounds (set via setBounds) respecting optional effects such as alpha (set via setAlpha) and color filter (set via setColorFilter). final Rect getBounds() Return the drawable's bounds Rect. Drawable.Callback getCallback() Return the current Drawable.Callback implementation attached to this Drawable. int getChangingConfigurations() Return a mask of the configuration parameters for which this drawable may change, requiring that it be re-created. Drawable.ConstantState getConstantState() Return a Drawable.ConstantState instance that holds the shared state of this Drawable. Drawable getCurrent() int getIntrinsicHeight() Return the intrinsic height of the underlying drawable object. int getIntrinsicWidth() Return the intrinsic width of the underlying drawable object. final int getLevel() Retrieve the current level. int getMinimumHeight() Returns the minimum height suggested by this Drawable. int getMinimumWidth() Returns the minimum width suggested by this Drawable. abstract int getOpacity() Return the opacity/transparency of this Drawable. boolean getPadding(Rect padding) Return in padding the insets suggested by this Drawable for placing content inside the drawable's bounds. int[] getState() Describes the current state, as a union of primitve states, such as state_focused, state_selected, etc. Region getTransparentRegion() Returns a Region representing the part of the Drawable that is completely transparent. void inflate(Resources r, XmlPullParser parser, AttributeSet attrs) Inflate this Drawable from an XML resource. void invalidateSelf() Use the current Drawable.Callback implementation to have this Drawable redrawn. boolean isStateful() Indicates whether this view will change its appearance based on state. final boolean isVisible() void jumpToCurrentState() If this Drawable does transition animations between states, ask that it immediately jump to the current state and skip any active animations. Drawable mutate() Make this drawable mutable. void onBoundsChange(Rect bounds) Override this in your subclass to change appearance if you recognize the specified state. boolean onLevelChange(int level) Override this in your subclass to change appearance if you vary based on level. boolean onStateChange(int[] state) Override this in your subclass to change appearance if you recognize the specified state. static int resolveOpacity(int op1, int op2) Return the appropriate opacity value for two source opacities. void scheduleSelf(Runnable what, long when) Use the current Drawable.Callback implementation to have this Drawable scheduled. abstract void setAlpha(int alpha) Specify an alpha value for the drawable. void setBounds(int left, int top, int right, int bottom) Specify a bounding rectangle for the Drawable. void setBounds(Rect bounds) Specify a bounding rectangle for the Drawable. final void setCallback(Drawable.Callback cb) Bind a Drawable.Callback object to this Drawable. void setChangingConfigurations(int configs) Set a mask of the configuration parameters for which this drawable may change, requiring that it be re-created. abstract void setColorFilter(ColorFilter cf) Specify an optional colorFilter for the drawable. void setColorFilter(int color, PorterDuff.Mode mode) Specify a color and porterduff mode to be the colorfilter for this drawable. void setDither(boolean dither) Set to true to have the drawable dither its colors when drawn to a device with fewer than 8-bits per color component. void setFilterBitmap(boolean filter) Set to true to have the drawable filter its bitmap when scaled or rotated (for drawables that use bitmaps). final boolean setLevel(int level) Specify the level for the drawable. boolean setState(int[] stateSet) Specify a set of states for the drawable. boolean setVisible(boolean visible, boolean restart) Set whether this Drawable is visible. void unscheduleSelf(Runnable what) Use the current Drawable.Callback implementation to have this Drawable unscheduled.
From class java.lang.Object Object clone() Creates and returns a copy of this Object. boolean equals(Object o) Compares this instance with the specified object and indicates if they are equal. void finalize() Invoked when the garbage collector has detected that this instance is no longer reachable. final Class<?> getClass() Returns the unique instance of Class that represents this object's class. int hashCode() Returns an integer hash code for this object. final void notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. final void notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. String toString() Returns a string containing a concise, human-readable description of this object. final void wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object. final void wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires. final void wait(long millis) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
From interface android.graphics.drawable.Drawable.Callback abstract void invalidateDrawable(Drawable who) Called when the drawable needs to be redrawn. abstract void scheduleDrawable(Drawable who, Runnable what, long when) A Drawable can call this to schedule the next frame of its animation. abstract void unscheduleDrawable(Drawable who, Runnable what) A Drawable can call this to unschedule an action previously scheduled with scheduleDrawable(Drawable, Runnable, long).