I started implementation of android live wallpaper, following the examples and tutorials found on the internet, and I can't include png background as wallpaper. Also checked with similar problems here, and still can't make it work.
This is the code:
public class LiveWallpaper extends WallpaperService {
/* IDs of recurces needed for animations*/
private SurfaceHolder holder;
private static final String TAG = "MyActivity";
#Override
public void onCreate() {
super.onCreate();
}
#Override
public void onDestroy() {
super.onDestroy();
}
#Override
public Engine onCreateEngine() {
return new WallpaperEngine();
}
class WallpaperEngine extends Engine {
public final Runnable mDrawWallpaper = new Runnable(){
public void run(){
drawWallpaper();
}
};
#Override
public void onCreate(SurfaceHolder surfaceHolder){
super.onCreate(surfaceHolder);
setTouchEventsEnabled(false);
loadImagesIntoMemory(R.drawable.wallpaper);
holder = getSurfaceHolder();
}
void drawWallpaperContent(Canvas c, int resourceId){
Bitmap decodeResoure = BitmapFactory.decodeResource (getResources(), resourceId);
c.drawBitmap(decodeResoure, 0, 0, null);
}
void drawWallpaper(){
final SurfaceHolder holder = getSurfaceHolder();
Canvas c = null;
c = holder.lockCanvas();
if(c!=null){
c.save();
drawWallpaperContent(c, R.drawable.wallpaper);
c.restore();
}
}
private void loadImagesIntoMemory(int resourceId){
Resources res = getResources();
BitmapFactory.decodeResource(res, resourceId);
}
#Override
public void onDestroy(){
super.onDestroy();
mHandler.removeCallbacks(mDrawWallpaper);
}
}
}
Bitmap is stored in drawable folder, and the version of android sdk is 2.2.
After launching the live wallpaper, I only get 'Loading Wallpaper' without showing the wallpaper image.
Does anyone knows what could be the problem?
Thank you.
Dj.
use this in your draw
' Bitmap image = BitmapFactory.decodeResource(getResources(),R.drawable.image);'
canvas.drawBitmap(image, 0, 0, paint);
you can pass null in paint parameter. m using this and its working
I struggled with a similar problem, c.drawColor(0xff000000); before drawing the bitmap was the solution for me.
Related
To preface, I'm probably going to work with Views instead of SurfaceView given this weird interaction, but my curiosity is getting the better of me and I want to know what's going on.
So I have a matrix class variable. I run matrix.setTranslate() once, and every other frame I say matrix.setTranslate(). After this I call canvas.drawBitmap(, matrix, null). After 100 frames, I stop drawing the bitmap.
Here's the code:
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
// matrix = new Matrix(); //Doesn't matter if I add this.
// matrix.reset(); //This doesn't matter either.
if (!once) {
matrix.setTranslate(100, 100);
} else {
matrix.setTranslate(800,800);
}
once = true;
if (++timer < 100) {
canvas.drawBitmap(ball, matrix, null);
}
}
What I expect to happen: Three possibilities.
Only the bottom right bitmap is visible since the entire screen was invalidated
Both bitmaps are visible because SurfaceView was smart with the dirty rectangle
Nothing is shown because nothing was drawn.
What actually happens: The top left bitmap blinks, bottom right bitmap displays solidly.
I'm pretty sure I have all of my bases covered:
All class variables are properly set in the constructor.
SurfaceView.onDraw() is called every 33 millis in its own thread.
Thread calls lockCanvas, then onDraw, then unlockCanvasAndPost
So, what's going on here? And bonus question, do these ghost images consume any extra resources and how can I clear them?
Rest of the code, mostly boilerplate:
public class FullscreenActivity extends Activity {
GameSurface ball;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ball = new GameSurface(this);
setContentView(ball);
}
}
class GameSurface extends SurfaceView implements SurfaceHolder.Callback {
GameThread thread;
boolean once = false;
Bitmap ball;
Matrix matrix;
int timer = 0;
public GameSurface(Context context) {
super(context);
ball = BitmapFactory.decodeResource(getResources(),R.drawable.football);
matrix = new Matrix();
getHolder().addCallback(this);
setFocusable(true);
}
#Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
// matrix = new Matrix(); //Doesn't matter if I add this.
// matrix.reset(); //This doesn't matter either.
if (!once) {
matrix.setTranslate(100, 100);
} else {
matrix.setTranslate(800,800);
}
//matrix.postRotate(timer); //For even more weirdness...
once = true;
if (++timer < 100) {
canvas.drawBitmap(ball, matrix, null);
}
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
thread = new GameThread(getHolder(), this);
thread.setRunning(true);
thread.start();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
class GameThread extends Thread {
private SurfaceHolder surfaceHolder;
private GameSurface gameView;
private boolean run = false;
public GameThread(SurfaceHolder surfaceHolder, GameSurface gameView) {
this.surfaceHolder = surfaceHolder;
this.gameView = gameView;
}
public void setRunning(boolean run) {
this.run = run;
}
#Override
public void run() {
Canvas c;
while (run) {
c = null;
try {
Thread.sleep(33);
}
catch(InterruptedException e) {}
try {
c = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
gameView.onDraw(c);
}
} finally {
if (c != null) {
surfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
}
I have this android application.
It use a SurfaceView, from where I get the Surface through the SurfaceHolder.
It also use ExoPlayer to stream videos. However I have instantiated an ImageReader, getting its Surface and passing to the ExoPlayer.
Now, I am in the ImageReader.OnImageAvailableListener#onImageAvailable and I access the latest Image.
I want to manipulate the Image and send the new data to the "SurfaceView" Surface.
How can I "draw" an android.media.Image to an android.view.Surface ?
The question is not clear to me.
The way to get android.media.Image is by the Camera2 API, and there you can provide a surface and the "camera" will draw over it. Please refer to Camera2Video example
Another way to get the Image object is from ImageReader (while decoding video for example). In this case you want to draw the image, but you can not provide a surface to the ImageReader(there is an internal surface that is not displayed). In this case you can draw the Image on a SurfaceView.
Assuming this is the case, you need to convert an Image to a Bitmap objects.
You have discussion about how perform this here
Possible duplicate of: how to draw image on surfaceview android
First get your canvas by using lockCanvas() (see here), second get your image and make it a drawable using:
my_bitmap = Bitmap.createBitmap(
MediaStore.Images.Media.getBitmap(getContentResolver(), uri),
0,0,90, 90);
drawable=new BitmapDrawable(my_bitmap);
After that you can draw the drawable to the locked canvas and use unlockCanvasAndPost (Canvas canvas) to post the updated canvas back to the surfaceview.
here is the answer for your question.
MainActivity.java
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mySurfaceView mySurfaceView = new mySurfaceView(getApplicationContext());
setContentView(mySurfaceView);
}
}
mySurfaceView.java
public class mySurfaceView extends SurfaceView implements
SurfaceHolder.Callback {
private TutorialThread _thread;
public mySurfaceView(Context context) {
super(context);
getHolder().addCallback(this);
_thread = new TutorialThread(getHolder(), this);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Bitmap _scratch = BitmapFactory.decodeResource(getResources(),
R.drawable.icon);
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(_scratch, 10, 10, null);
}
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
}
public void surfaceCreated(SurfaceHolder arg0) {
_thread.setRunning(true);
_thread.start();
}
public void surfaceDestroyed(SurfaceHolder arg0) {
boolean retry = true;
_thread.setRunning(false);
while (retry) {
try {
_thread.join();
retry = false;
} catch (InterruptedException e) {
}
}
}
class TutorialThread extends Thread {
private SurfaceHolder _surfaceHolder;
private mySurfaceView _panel;
private boolean _run = false;
public TutorialThread(SurfaceHolder surfaceHolder, mySurfaceView panel) {
_surfaceHolder = surfaceHolder;
_panel = panel;
}
public void setRunning(boolean run) {
_run = run;
}
#Override
public void run() {
Canvas c;
while (_run) {
c = null;
try {
c = _surfaceHolder.lockCanvas(null);
synchronized (_surfaceHolder) {
_panel.onDraw(c);
}
} finally {
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
}
I need to create a live wallpaper where it just pulls an image from the drawable directory.
Is there an example somewhere that I can refer to?
It would be nice if the example also shows how to draw something simple on top of the image as well. If not, its ok =)
the one on the Android.com site just has drawing a cube =(
thanks for any comment
It is very easy))). Use something like this.
In your Engine constructor use something like this
Bitmap _background = BitmapFactory.decodeResource(getResources(), R.drawable.test);
and in your code use this
private final int WEATHER_ANIMATION_INTERVAL = 1000;
private final Handler _handler = new Handler();
private final Runnable weatherAnimation = new Runnable()
{
#Override
public void run()
{
drawNextFrame();
}
};
private void drawNextFrame()
{
final SurfaceHolder holder = getSurfaceHolder();
try {
_canvas = holder.lockCanvas();
if (_canvas != null)
{
drawAnimation(_canvas);
}
}
finally
{
if (_canvas != null)
holder.unlockCanvasAndPost(_canvas);
}
// schedule the next frame
_handler.removeCallbacks(weatherAnimation);
if (_visible)
{
_handler.postDelayed(weatherAnimation, WEATHER_ANIMATION_INTERVAL);
}
return;
}
private void drawAnimation(Canvas c)
{
c.drawBitmap(_background, _xOffset, _yOffset, _paint);
_weather.draw(c, _xOffset, _yOffset, _paint);
}
I hope this help you
I am working on streaming a video from web. Where I decode the video/audio stuff in native code and get the raw pixels for video
I create a bitmap in java code, with surfaceholder and canvas and update pixels for each bitmap from native code and then stream the bitmaps as video. My problem here is, the video crashes after a few seconds because of low memory.
I want to know whether there is anything that i need to make sure to not to crash app and use low memory.
Here is my code.
public CanvasThread(SurfaceHolder surfaceHolder, Panel panel) {
_surfaceHolder = surfaceHolder;
_panel = panel; }
public void setRunning(boolean run) {
_run = run; }
#Override
public void run() {
Canvas c;
while (_run) {
c = null;
try {
c = _surfaceHolder.lockCanvas(null);
synchronized (_surfaceHolder) {
_panel.onDraw(c);
}
} finally {
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
public class Panel extends SurfaceView implements SurfaceHolder.Callback{
private CanvasThread canvasthread;
private static Bitmap mBitmap;
private static boolean ii=false;
public Panel(Context context, AttributeSet attrs) {
super(context, attrs);
getHolder().addCallback(this);
canvasthread = new CanvasThread(getHolder(), this);
setFocusable(true);
mBitmap=Bitmap.createBitmap(480, 320, Bitmap.Config.RGB_565);//bitmap created in constructor
}
public Panel(Context context) {
super(context);
getHolder().addCallback(this);
canvasthread = new CanvasThread(getHolder(), this);
setFocusable(true);
}
private static native void renderbitmap(Bitmap bitmap); //native function
#Override
public void onDraw(Canvas canvas) {
renderbitmap(mBitmap); //Update pixels from native code
canvas.drawBitmap(mBitmap, 0,0,null);//draw on canvas
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) { }
#Override
public void surfaceCreated(SurfaceHolder holder) {
canvasthread.setRunning(true);
canvasthread.start(); }
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
boolean retry = true;
canvasthread.setRunning(false);
while (retry) {
try {
canvasthread.join();
retry = false;
} catch (InterruptedException e) { }
}
You might check out Richard Quirk's glbuffer. I'm using it in a video player app.
In general you want to hold on to the video packets you're receiving and only decode them right before they are needed for display. It should be easy to integrate your code with glbuffer and bypass any Bitmap allocation in Java code.
There would be one decoded frame at any given time present in the native code and in GL texture memory and several encoded packets that you're keeping around for buffering.
That will probably not because you have limited amount of memory. Probably around 16MB for the emulator. You should not store all the images in memory. You have to options
Fix your algorithm so it doesn't
need everything in memory
Or only keep one image in memory and
the rest on disk
From a quick scan of your code, it looks like your basic problem is that you're creating a new bitmap each time your OnDraw method is called. Instead, comment that line out, and create the bitmap for mBitmap just once at startup.
I'd like to open up a SurfaceView with a icon placed in the center of the screen when an application is first started. I'm evoking icon creation using an implementation of SurfaceHolder.Callback to track when the 'Canvas' object is ready. My question is is there a better way? Are there less cumbersome methods of starting a SurfaceView with some Drawables loaded on creation without having to resort to placing draw logic within a callback object?
Here's my code for reference. First the object which does drawing:
public class CanvasDraw{
protected final SurfaceHolder mHolder;
protected final Drawable mDrawable;
public interface DrawLogic{
void draw(Rect _surface);
}
public CanvasDraw(SurfaceView _view, Drawable _drawable){
mHolder = _view.getHolder();
mDrawable = _drawable;
}
public void draw(DrawLogic _logic){
Canvas canvas = null;
try{
canvas = mHolder.lockCanvas();
if( canvas != null ){
Log.i("DRAWABLE", "Drawing " + mDrawable.toString());
_logic.draw( mHolder.getSurfaceFrame() );
mDrawable.draw(canvas);
}
else{
Log.i("DRAWABLE", "Canvas null valued");
}
}
finally{
if( canvas != null ){
mHolder.unlockCanvasAndPost(canvas);
}
}
}
}
and then my private callback object:
private class DrawOnceCallback implements SurfaceHolder.Callback {
private final SurfaceHolder mHolder;
public DrawOnceCallback(SurfaceHolder _holder ){
mHolder = _holder;
mHolder.addCallback(this);
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {}
#Override
public void surfaceCreated(SurfaceHolder holder) {
Log.i("SURFACEHOLDER","Surface created. Canvas available.");
mDrawTiles.draw( new CanvasDraw.DrawLogic(){
#Override
public void draw(Rect _surface) {
mTiles.setBounds(
_surface.centerX() - mDrawWidth/2,
_surface.centerY() - mDrawHeight/2,
_surface.centerX() + mDrawHeight/2,
_surface.centerY() + mDrawHeight/2);
}
});
mHolder.removeCallback(this);
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {Log.i("SURFACEHOLDER","Surface destroyed.");}
}
I did something like this simply by assigning the image I wanted to a view in the layout XML file. If you've got to wait until your canvas and all that is ready anyways why not just use a default property? My opening splash screen was just a view with
android:background="#drawable/splash"
added to its layout.