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Is it possible to split an image into many parts in Android?

I'm creating a puzzle game where the player can choose a picture and then the program splits it into multi-parts.
I tried to search on many posts answers for my problem, but all of them are talking about BufferedImage or Graphic components. I'm coding on android studio to export my application later, and BufferedImage, Graphics, and others are not known by android. So I think that I should use BitmapDrawable to manipulate my images.
public void initImage(int image) {
this.base = setImage(puzzle.getApplicationContext(), image, 800, 800);
}
public BitmapDrawable setImage(final Context c, final int ressource, final int w, final int h)
{
try {
Drawable dr = c.getResources().getDrawable(ressource);
Bitmap bitmap = ((BitmapDrawable) dr).getBitmap();
return new BitmapDrawable(c.getResources(), Bitmap.createScaledBitmap(bitmap, w, h, true));
} catch(ClassCastException cce) { cce.printStackTrace(); return null; }
}
#Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(this.base.getBitmap(), 0, 0, null);
}
I draw my first image, and now I want to split it into multi parts.
If anyone could help me, I would be very grateful. :)

Android, creating custom ImageView shape

I need to create a view that is filled with a dynamic color at runtime. I've accomplished this task however the actual view needs to have a "peak" on the right side. Typically ImageView's are only square or rectangular. Does anyone know how I would accomplish adding a triangular peak to the view?
For example:

You can override the onDraw event of the ImageView and do whatever you need with the canvas object.
public class MyImageView extends ImageView {
...
#Override
public void onDraw(Canvas canvas){
super.onDraw(canvas);
Point[] point = ... //create three points here for the triangle
Paint paint = ... // create your desired color
drawTriangle(canvas, point, paint);
}
And for the triagle draw (see this SO answer):
private void drawTriangle(Canvas canvas, Point[] point, Paint paint) {
float [] points = new float[8];
points[0] = point[0].x;
points[1] = point[0].y;
points[2] = point[1].x;
points[3] = point[1].y;
points[4] = point[2].x;
points[5] = point[2].y;
points[6] = point[0].x;
points[7] = point[0].y;
canvas.drawVertices(VertexMode.TRIANGLES, 8, points, 0, null, 0, null, 0, null, 0, 0, paint);
Path path = new Path();
path.moveTo(point[0].x , point[0].y);
path.lineTo(point[1].x,point[1].y);
path.lineTo(point[2].x,point[2].y);
canvas.drawPath(path,paint);
}

How to use BitmapShader without repeat

I want to create a heart shape drown on screen when user touches the smartphone screen(working on a drawing android app). So i setup the BitmapShader as below code
//Initialize the bitmap object by loading an image from the resources folder
Bitmap fillBMP = BitmapFactory.decodeResource(context.getResources(), R.drawable.heart);
fillBMP = Bitmap.createScaledBitmap(fillBMP, 20, 20, false);
//Initialize the BitmapShader with the Bitmap object and set the texture tile mode
shader= new BitmapShader(fillBMP, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
Then i assign the shader paint object.
paint.setShader(preset.shader);
I have also setup the touch listener to track the user finger. On user touch i draw this on canvas object as.
Path path = new Path();
path.moveTo(mid1.x, mid1.y);
path.quadTo(midmid.x, midmid.y, mid2.x, mid2.y);
canvas.drawPath(path, paint);
This give me this
Where some heart shape are croped and also these are repeated. What i want not these are repeated and never croped like this.
Thanks in advance.

I had a bit of trouble uploading to Git, so for now, I'll post the solution here.
Here's a helper class I wrote to create the effect you want. I added comments in-line to explain what I'm doing.
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PathMeasure;
// Use this class with a Canvas to create the effect you want.
public class CurvedBitmapDrawer
{
private Context mContext;
private Paint mPaint;
private int mResourceId;
private Bitmap mBitmap;
private Path mPath;
private int mBitmapMargin;
// Create with a context so that this class can use resource ids.
public CurvedBitmapDrawer(Context context) {
mContext = context;
mPath = new Path();
}
// getters setters for paint.
// this paint will be used to draw the bitmaps, and the strokeWidth value in the paint
// will be used to set the thickness of the curve / line that is drawn.
public Paint getPaint() {
return mPaint;
}
public void setPaint(Paint paint) {
mPaint = paint;
}
// getters setters for the space between the bitmaps.
public int getBitmapMargin()
{
return mBitmapMargin;
}
public void setBitmapMargin(int bitmapMargin)
{
mBitmapMargin = bitmapMargin;
}
// getters setters for res id
public int getResourceId() {
return mResourceId;
}
public void setResourceId(int resourceId)
{
mResourceId = resourceId;
mBitmap = null;
}
// alternative optional getters setters for bitmap.
public Bitmap getBitmap()
{
return mBitmap;
}
public void setBitmap(Bitmap bitmap)
{
mBitmap = bitmap;
mResourceId = 0;
}
// I decided to only use a local path here, but feel free to change it.
// call getPath to perform actions on the path that is drawn by this class.
public Path getPath()
{
return mPath;
}
// draw method. comments inline.
public void draw(Canvas canvas)
{
// grab a bitmap in the desired size.
final Bitmap scaledBitmap = getScaledBitmap();
// find the center of the bitmap.
final float centerX = scaledBitmap.getWidth() / 2;
final float centerY = scaledBitmap.getHeight() / 2;
// wrap the path with a measurement tool for paths - PathMeasure
final PathMeasure pathMeasure = new PathMeasure(mPath, false);
// initialize the distance to the center of the bitmap.
float distance = scaledBitmap.getWidth() / 2;
// initialize position and slope buffers.
float[] position = new float[2];
float[] slope = new float[2];
float slopeDegree;
// draw so long as the distance traveled on the path isn't longer than
// the total distance of the path.
while (distance < pathMeasure.getLength())
{
// grab the position & slope (tangent) on a particular distance along the path.
pathMeasure.getPosTan(distance, position, slope);
// convert the vector to a degree.
slopeDegree = (float)((Math.atan2(slope[1], slope[0]) * 180f) / Math.PI);
// preserve the current state of the canvas
canvas.save();
// translate the canvas to the position on the path.
canvas.translate(position[0] - centerX, position[1] - centerY);
// rotate the canvas around the center of the bitmap the amount of degrees needed.
canvas.rotate(slopeDegree, centerX, centerY);
// draw the bitmap
canvas.drawBitmap(scaledBitmap, 0, 0, mPaint);
// revert the bitmap to the previous state
canvas.restore();
// increase the distance by the bitmap's width + the desired margin.
distance += scaledBitmap.getWidth() + mBitmapMargin;
}
}
// returns a scaled bitmap from the asset specified.
private Bitmap getScaledBitmap()
{
// no bitmap or resId, return null (no special handing of this! add if you like).
if (mBitmap == null && mResourceId == 0)
return null;
// if no bitmap is specified, create one from the resource id.
// Optimization: be sure to clear the bitmap once done.
if (mBitmap == null)
mBitmap = BitmapFactory.decodeResource(mContext.getResources(), mResourceId);
// width / height of the bitmap[
float width = mBitmap.getWidth();
float height = mBitmap.getHeight();
// ratio of the bitmap
float ratio = width / height;
// set the height of the bitmap to the width of the path (from the paint object).
float scaledHeight = mPaint.getStrokeWidth();
// to maintain aspect ratio of the bitmap, use the height * ratio for the width.
float scaledWidth = scaledHeight * ratio;
// return the generated bitmap, scaled to the correct size.
return Bitmap.createScaledBitmap(mBitmap, (int)scaledWidth, (int)scaledHeight, true);
}
}
Here's a usage example:
ImageView image = (ImageView)findViewById(R.id.img);
CurvedBitmapDrawer drawer = new CurvedBitmapDrawer(this);
Paint paint = new Paint();
paint.setStrokeWidth(50);
drawer.setPaint(paint);
drawer.setResourceId(R.drawable.heart_icon);
drawer.setBitmapMargin(10);
Path path = drawer.getPath();
path.moveTo(80, 90);
path.cubicTo(160, 470, 750, 290, 440, 880);
Bitmap finalBitmap = Bitmap.createBitmap(800, 1000, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(finalBitmap);
drawer.draw(canvas);
image.setImageBitmap(finalBitmap);
I've tested it here and it seems to work well, minus some edge cases perhaps. Here's what it looks like with the given usage example:
Remember to set the stroke width on the paint object you supply, or else nothing will be drawn (and probably will cause an exception with the current code).
Hope this helps you.

Animate rotation of an image in Android

I have a gear image which I want to continuously rotate about a fixed point.
Earlier I was accomplishing this by including the image in my Android class as an ImageView and applying a RotateAnimation to it.
#InjectView(R.id.gear00) ImageView gear00;
RotateAnimation ra07 = new RotateAnimation(0, 359, 129, 186);
ra07.setDuration(10000);
ra07.setRepeatCount(RotateAnimation.INFINITE);
ra07.setInterpolator(new LinearInterpolator());
gear00.setAnimation(ra07);
Basically, I was injecting the ImageView into the class and applying a rotation animation.
However, I dont have the luxury of using an ImageView anymore. I have to use a Bitmap and rotate it on the canvas.
How can I go about accomplishing what I was doing earlier in the onDraw() method with a bitmap rotating about a fixed point continiously on the canvas?
Edit1:
I tried one of the suggestions mentioned below my code looks a little like the following
in onCreate():
Matrix matrix = new Matrix();
matrix.setRotate(10, 100, 200);
Then in onDraw() (where gear00Scaled is a bitmap to be rotated on the canvas):
canvas.drawBitmap(gear00Scaled, matrix, new Paint());
Another method I tried involved saving the canvas, rotating it, then restoring it:
canvas.save();
canvas.rotate(10);
canvas.drawBitmap(gear00Scaled, 100, 200, null);
canvas.restore();
Neither seem to be working though!

Make an XML class (suppose: rotate.xml) and place it in res/anim folder and then write the following code in it:
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="0"
android:interpolator="#android:anim/linear_interpolator"
android:pivotX="50%"
android:pivotY="50%"
android:repeatCount="infinite"
android:toDegrees="360" />
Then in your java class, do the following in OnCreate:
final Animation a = AnimationUtils.loadAnimation(CustomActivity.this,
R.anim.rotate);
a.setDuration(3000);
gear00.startAnimation(a);
OR
To do it using bitmap, I hope the following sequence of code helps you:
Bitmap targetBitmap = Bitmap.createBitmap(targetWidth, targetHeight, config);
Canvas canvas = new Canvas(targetBitmap);
Matrix matrix = new Matrix();
matrix.setRotate(mRotation,source.getWidth()/2,source.getHeight()/2);
canvas.drawBitmap(source, matrix, new Paint());
If you check the following method from:
~frameworks\base\graphics\java\android\graphics\Bitmap.java
public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height,
Matrix m, boolean filter)
this would explain what it does with rotation and translate.

I want to rotate a custom image as progress dialog in my application. You can use the code below to rotate an image:
RotateAnimation anim = new RotateAnimation(0.0f, 360.0f ,
Animation.RELATIVE_TO_SELF, .5f, Animation.RELATIVE_TO_SELF, .5f);
anim.setInterpolator(new LinearInterpolator());
anim.setRepeatCount(Animation.INFINITE);
anim.setDuration(1000);
imageView.setAnimation(anim);
imageView.startAnimation(anim);

In your onCreate() do
Matrix matrix = new Matrix();
And in onDraw
float angle = (float) (System.currentTimeMillis() % ROTATE_TIME_MILLIS)
/ ROTATE_TIME_MILLIS * 360;
matrix.reset();
matrix.postTranslate(-source.getWidth() / 2, -source.getHeight() / 2);
matrix.postRotate(angle);
matrix.postTranslate(centerX, centerY)
canvas.drawBitmap(source, matrix, null);
invalidate(); // Cause a re-draw
ROTATE_TIME_MILLIS is the full circle time, e.g. 2000 is 2 seconds.

Two things before the code:
You can't use imageview at all at all? Cause you could link it to a canvas and use a bitmap, but it is still an imageview.
I believe the main issue you are having is the other answer is not animating it and you are missing the call to invalidate() the view and redraw it as rotated.
So there are two approaches:
1st is with the imageview, personally I think it is easier and nicer. Below is a method in my activity class and mLittleChef is an ImageView.
public void doCanvas(){
//Create our resources
Bitmap bitmap = Bitmap.createBitmap(mLittleChef.getWidth(), mLittleChef.getHeight(), Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
final Bitmap chefBitmap = BitmapFactory.decodeResource(getResources(),R.drawable.dish_special);
//Link the canvas to our ImageView
mLittleChef.setImageBitmap(bitmap);
ValueAnimator animation= ValueAnimator.ofFloat(0, 359, 129, 186);
animation.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator animation) {
float value = (Float) animation.getAnimatedValue();
//Clear the canvas
canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
canvas.save();
canvas.rotate(value, canvas.getWidth()/2, canvas.getHeight()/2);
canvas.drawBitmap(chefBitmap, 0, 0, null);
canvas.restore();
mLittleChef.invalidate();
}
});
animation.setInterpolator(new LinearInterpolator());
animation.setDuration(1000);
animation.start();
}
The other way to do it is with a custom canvas class. Instead of an ImageView, I create my own custom view class for ExampleDrawView mLittleChefDraw; in my layout. You will probably have to monkey with this one a bit to get exactly what you are looking for in terms of rotation, I made it just do a 360 degree turn using the middle of the canvas as the pivot point.
public class ExampleDrawView extends View {
Bitmap bitmap;
Float mRotate= 0f;
Handler h;
//State variables
final int STATE_PAUSE = 2;
final int STATE_ROTATE = 3;
int STATE_CURRENT;
public ExampleDrawView(Context context, AttributeSet attrs) {
super(context, attrs);
h = new Handler();
bitmap= BitmapFactory.decodeResource(getResources(), R.drawable.dish_special);
STATE_CURRENT= STATE_PAUSE;
}
Runnable move = new Runnable() {
#Override
public void run() {
switch (STATE_CURRENT){
case STATE_ROTATE:
if (mRotate<360){
mRotate++;
invalidate();
}else{
STATE_CURRENT= STATE_PAUSE;
}
h.postDelayed(move, 20);
break;
}
}
};
public void startDrawing(){
if(STATE_CURRENT == STATE_PAUSE){
STATE_CURRENT= STATE_ROTATE;
mRotate=(float) 0;
h.postDelayed(move, 20);
}
}
#Override
protected void onDraw(Canvas canvas){
super.onDraw(canvas);
//change your rotate point here, i just made it the middle of the canvas
canvas.rotate(mRotate,getWidth()/2,getHeight()/2);
canvas.drawBitmap(bitmap, 0, 0, null);
}
}
And then back in the activity call this to start it:
public void doCanvasCustomView(){
mLittleChefDraw.startDrawing();
}

Android Custom Brush Colors

I'm trying to make custom brushes for my Android painting app. I started with Michael's code (found here) and I have managed to get .png brushes and use that as a bitmap and redraw it. It works fine but I can't change the colour. Tried using the setcolorfilter and colormatrixfilter but it doesn't seem to be working. Anyone knows how I can do this?
private Bitmap mBitmapBrush;
private Vector2 mBitmapBrushDimensions;
private List<Vector2> mPositions = new ArrayList<Vector2>(100);
private Paint mPanit;
public MyView(Context c) {
super(c);
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
mBitmapBrush = BitmapFactory.decodeResource(c.getResources(),R.drawable.brush1);
mBitmapBrushDimensions = new Vector2(mBitmapBrush.getWidth(), mBitmapBrush.getHeight());
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(0xFFAAAAAA);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
for (Vector2 pos : mPositions) {
canvas.drawBitmap(mBitmapBrush, pos.a, pos.b, mPanit);
}
invalidate();
}
When I tried using the Colormatrixfilter, the .set function was giving an error.

I had the same issue. In order to change the bitmap color you need to add color to your paint object and apply it into bitmap. See the working example here,
for (Vector2 pos : customBrushMap.get(p)) {
Paint paint = new Paint();
ColorFilter filter = new PorterDuffColorFilter(R.Color.GREEN, PorterDuff.Mode.SRC_IN);
paint.setColorFilter(filter);
canvas.drawBitmap(mBitmapBrush, pos.x, pos.y, paint);
}
Result,