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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* 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.graphics;
/**
* The NinePatch class permits drawing a bitmap in nine or more sections.
* Essentially, it allows the creation of custom graphics that will scale the
* way that you define, when content added within the image exceeds the normal
* bounds of the graphic. For a thorough explanation of a NinePatch image,
* read the discussion in the
* 2D
* Graphics document.
*
* The Draw 9-Patch
* tool offers an extremely handy way to create your NinePatch images,
* using a WYSIWYG graphics editor.
*
*/
public class NinePatch {
private final Bitmap mBitmap;
/**
* Used by native code. This pointer is an instance of Res_png_9patch*.
*
* @hide
*/
public final int mNativeChunk;
private Paint mPaint;
private String mSrcName;
/**
* Create a drawable projection from a bitmap to nine patches.
*
* @param bitmap The bitmap describing the patches.
* @param chunk The 9-patch data chunk describing how the underlying bitmap
* is split apart and drawn.
*/
public NinePatch(Bitmap bitmap, byte[] chunk) {
this(bitmap, chunk, null);
}
/**
* Create a drawable projection from a bitmap to nine patches.
*
* @param bitmap The bitmap describing the patches.
* @param chunk The 9-patch data chunk describing how the underlying
* bitmap is split apart and drawn.
* @param srcName The name of the source for the bitmap. Might be null.
*/
public NinePatch(Bitmap bitmap, byte[] chunk, String srcName) {
mBitmap = bitmap;
mSrcName = srcName;
mNativeChunk = validateNinePatchChunk(mBitmap.ni(), chunk);
}
/**
* @hide
*/
public NinePatch(NinePatch patch) {
mBitmap = patch.mBitmap;
mSrcName = patch.mSrcName;
if (patch.mPaint != null) {
mPaint = new Paint(patch.mPaint);
}
// No need to validate the 9patch chunk again, it was done by
// the instance we're copying from
mNativeChunk = patch.mNativeChunk;
}
@Override
protected void finalize() throws Throwable {
try {
nativeFinalize(mNativeChunk);
} finally {
super.finalize();
}
}
/**
* Returns the name of this NinePatch object if one was specified
* when calling the constructor.
*/
public String getName() {
return mSrcName;
}
/**
* Returns the paint used to draw this NinePatch. The paint can be null.
*
* @see #setPaint(Paint)
* @see #draw(Canvas, Rect)
* @see #draw(Canvas, RectF)
*/
public Paint getPaint() {
return mPaint;
}
/**
* Sets the paint to use when drawing the NinePatch.
*
* @param p The paint that will be used to draw this NinePatch.
*
* @see #getPaint()
* @see #draw(Canvas, Rect)
* @see #draw(Canvas, RectF)
*/
public void setPaint(Paint p) {
mPaint = p;
}
/**
* Returns the bitmap used to draw this NinePatch.
*/
public Bitmap getBitmap() {
return mBitmap;
}
/**
* Draws the NinePatch. This method will use the paint returned by {@link #getPaint()}.
*
* @param canvas A container for the current matrix and clip used to draw the NinePatch.
* @param location Where to draw the NinePatch.
*/
public void draw(Canvas canvas, RectF location) {
canvas.drawPatch(this, location, mPaint);
}
/**
* Draws the NinePatch. This method will use the paint returned by {@link #getPaint()}.
*
* @param canvas A container for the current matrix and clip used to draw the NinePatch.
* @param location Where to draw the NinePatch.
*/
public void draw(Canvas canvas, Rect location) {
canvas.drawPatch(this, location, mPaint);
}
/**
* Draws the NinePatch. This method will ignore the paint returned
* by {@link #getPaint()} and use the specified paint instead.
*
* @param canvas A container for the current matrix and clip used to draw the NinePatch.
* @param location Where to draw the NinePatch.
* @param paint The Paint to draw through.
*/
public void draw(Canvas canvas, Rect location, Paint paint) {
canvas.drawPatch(this, location, paint);
}
void drawSoftware(Canvas canvas, RectF location, Paint paint) {
nativeDraw(canvas.mNativeCanvas, location, mBitmap.ni(), mNativeChunk,
paint != null ? paint.mNativePaint : 0, canvas.mDensity, mBitmap.mDensity);
}
void drawSoftware(Canvas canvas, Rect location, Paint paint) {
nativeDraw(canvas.mNativeCanvas, location, mBitmap.ni(), mNativeChunk,
paint != null ? paint.mNativePaint : 0, canvas.mDensity, mBitmap.mDensity);
}
/**
* Return the underlying bitmap's density, as per
* {@link Bitmap#getDensity() Bitmap.getDensity()}.
*/
public int getDensity() {
return mBitmap.mDensity;
}
/**
* Returns the intrinsic width, in pixels, of this NinePatch. This is equivalent
* to querying the width of the underlying bitmap returned by {@link #getBitmap()}.
*/
public int getWidth() {
return mBitmap.getWidth();
}
/**
* Returns the intrinsic height, in pixels, of this NinePatch. This is equivalent
* to querying the height of the underlying bitmap returned by {@link #getBitmap()}.
*/
public int getHeight() {
return mBitmap.getHeight();
}
/**
* Indicates whether this NinePatch contains transparent or translucent pixels.
* This is equivalent to calling getBitmap().hasAlpha() on this
* NinePatch.
*/
public final boolean hasAlpha() {
return mBitmap.hasAlpha();
}
/**
* Returns a {@link Region} representing the parts of the NinePatch that are
* completely transparent.
*
* @param bounds The location and size of the NinePatch.
*
* @return null if the NinePatch has no transparent region to
* report, else a {@link Region} holding the parts of the specified bounds
* that are transparent.
*/
public final Region getTransparentRegion(Rect bounds) {
int r = nativeGetTransparentRegion(mBitmap.ni(), mNativeChunk, bounds);
return r != 0 ? new Region(r) : null;
}
/**
* Verifies that the specified byte array is a valid 9-patch data chunk.
*
* @param chunk A byte array representing a 9-patch data chunk.
*
* @return True if the specified byte array represents a 9-patch data chunk,
* false otherwise.
*/
public native static boolean isNinePatchChunk(byte[] chunk);
/**
* Validates the 9-patch chunk and throws an exception if the chunk is invalid.
* If validation is successful, this method returns a native Res_png_9patch*
* object used by the renderers.
*/
private static native int validateNinePatchChunk(int bitmap, byte[] chunk);
private static native void nativeFinalize(int chunk);
private static native void nativeDraw(int canvas_instance, RectF loc, int bitmap_instance,
int c, int paint_instance_or_null, int destDensity, int srcDensity);
private static native void nativeDraw(int canvas_instance, Rect loc, int bitmap_instance,
int c, int paint_instance_or_null, int destDensity, int srcDensity);
private static native int nativeGetTransparentRegion(int bitmap, int chunk, Rect location);
}