Drawable.ConstantState
public static abstract class Drawable.ConstantState
extends Object
| java.lang.Object | |
| ↳ | android.graphics.drawable.Drawable.ConstantState |
This abstract class is used by Drawables to store shared constant state and data between Drawables. BitmapDrawables created from the same resource will for instance share a unique bitmap stored in their ConstantState.
newDrawable(android.content.res.Resources) can be used as a factory to create new Drawable instances from this ConstantState.
Drawable.getConstantState() to retrieve the ConstantState of a Drawable. Calling Drawable.mutate() on a Drawable should typically create a new ConstantState for that Drawable. Summary
Public constructors | |
|---|---|
ConstantState() | |
Public methods | |
|---|---|
boolean | canApplyTheme() Return whether this constant state can have a theme applied. |
abstract int | getChangingConfigurations() Return a bit mask of configuration changes that will impact this drawable (and thus require completely reloading it). |
Drawable | newDrawable(Resources res) Creates a new Drawable instance from its constant state using the specified resources. |
abstract Drawable | newDrawable() Creates a new Drawable instance from its constant state. |
Drawable | newDrawable(Resources res, Resources.Theme theme) Creates a new Drawable instance from its constant state using the specified resources and theme. |
Inherited methods | |
|---|---|
Public constructors
ConstantState
public ConstantState ()
Public methods
canApplyTheme
public boolean canApplyTheme ()
Return whether this constant state can have a theme applied.
| Returns | |
|---|---|
boolean | |
getChangingConfigurations
public abstract int getChangingConfigurations ()
Return a bit mask of configuration changes that will impact this drawable (and thus require completely reloading it).
newDrawable
public Drawable newDrawable (Resources res)
Creates a new Drawable instance from its constant state using the specified resources. This method should be implemented for drawables that have density-dependent properties.
The default implementation for this method calls through to newDrawable().
| Parameters | |
|---|---|
res | Resources: the resources of the context in which the drawable will be displayed This value may be null. |
| Returns | |
|---|---|
Drawable | a new drawable object based on this constant state This value cannot be null. |
newDrawable
public abstract Drawable newDrawable ()
Creates a new Drawable instance from its constant state.
Note: Using this method means density-dependent properties, such as pixel dimensions or bitmap images, will not be updated to match the density of the target display. To ensure correct scaling, use newDrawable(android.content.res.Resources) instead to provide an appropriate Resources object.
| Returns | |
|---|---|
Drawable | a new drawable object based on this constant state This value cannot be null. |
See also:
newDrawable
public Drawable newDrawable (Resources res, Resources.Theme theme)
Creates a new Drawable instance from its constant state using the specified resources and theme. This method should be implemented for drawables that have theme-dependent properties.
The default implementation for this method calls through to newDrawable(android.content.res.Resources).
| Parameters | |
|---|---|
res | Resources: the resources of the context in which the drawable will be displayed This value may be null. |
theme | Resources.Theme: the theme of the context in which the drawable will be displayed This value may be null. |
| Returns | |
|---|---|
Drawable | a new drawable object based on this constant state This value cannot be null. |