/*
* 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.graphics.drawable.shapes;
import android.annotation.NonNull;
import android.graphics.Canvas;
import android.graphics.Outline;
import android.graphics.Paint;
/**
* Defines a generic graphical "shape."
* Any Shape can be drawn to a Canvas with its own draw() method,
* but more graphical control is available if you instead pass
* it to a {@link android.graphics.drawable.ShapeDrawable}.
*/
public abstract class Shape implements Cloneable {
private float mWidth;
private float mHeight;
/**
* Returns the width of the Shape.
*/
public final float getWidth() {
return mWidth;
}
/**
* Returns the height of the Shape.
*/
public final float getHeight() {
return mHeight;
}
/**
* Draw this shape into the provided Canvas, with the provided Paint.
* Before calling this, you must call {@link #resize(float,float)}.
*
* @param canvas the Canvas within which this shape should be drawn
* @param paint the Paint object that defines this shape's characteristics
*/
public abstract void draw(Canvas canvas, Paint paint);
/**
* Resizes the dimensions of this shape.
* Must be called before {@link #draw(Canvas,Paint)}.
*
* @param width the width of the shape (in pixels)
* @param height the height of the shape (in pixels)
*/
public final void resize(float width, float height) {
if (width < 0) {
width = 0;
}
if (height < 0) {
height =0;
}
if (mWidth != width || mHeight != height) {
mWidth = width;
mHeight = height;
onResize(width, height);
}
}
/**
* Checks whether the Shape is opaque.
* Default impl returns true. Override if your subclass can be opaque.
*
* @return true if any part of the drawable is <em>not</em> opaque.
*/
public boolean hasAlpha() {
return true;
}
/**
* Callback method called when {@link #resize(float,float)} is executed.
*
* @param width the new width of the Shape
* @param height the new height of the Shape
*/
protected void onResize(float width, float height) {}
/**
* Compute the Outline of the shape and return it in the supplied Outline
* parameter. The default implementation does nothing and {@code outline} is not changed.
*
* @param outline The Outline to be populated with the result. Should not be null.
*/
public void getOutline(@NonNull Outline outline) {}
@Override
public Shape clone() throws CloneNotSupportedException {
return (Shape) super.clone();
}
}