Some small features of Android

1. Image compression

To load a picture from a directory:
Bitmap bm=bitmapfactory.decodefile ("/mnt/sdcard/xxx.bmp"); Load----Original Size
Iv.setimagebitmap (BM); Slow----speed
Compression loading:
When----------compression, you often calculate the compression factor
To get the screen width High:
WindowManager Widow=getwindowmanager ();
int Screenwidth=widow.getdefultdisplay (). GetWidth ();
int Screenheight=widow.getdefultdisplay.getheight ();
Get Picture Width Height:
Options ops=new options ();
Ops.injustdecodebounds=true; Loads only the properties of the picture.
Bitmap bm=bitmapfactory.decodefile ("/mnt/sdcard/xxx.bmp", OPS);
int Bmpwidth=ops.outwidth ();
int Bmpheight=ops.outheight ();
Calculate the compression scale:
int Times=1;
int wtims=bmpwidth/screenwidth;
int htimes=bmpheight/screenheight;
if (wtims>htimes) {times=wtims;}
Else{times=htimes;}

Ops.insamplesize=times; --------Compression ratio
Ops.injustdecodebounds=flase;
Bitmap bm=bitmapfactory.decodefile ("/mnt/sdcard/xxx.bmp", OPS);
Iv.setimagebitmap (BM);

2. Picture copy

public void Copyimage (view view) {
Bitmap BM;
1. Create a blank image
Bitmap Copybm=bitmap.createbitmap (Bm.getwidth (), Bm.getheight,bm.getconfig ());
2. Draw the contents of the old picture bm into the COPYBM
----Call the drawing () class
Canvas canvas=new canvas (COPYBM);
-----Matrix Rectangle Object
Matrix matrix=new Matrix ();
-----Paint Brush
Paint paint=new paint ();
Canvas.drawbitmap (Bm,matrix,paint); -----Matrix,paint

Iv.setimagebitmap (COPYBM);
}

' 3, tear the clothes

Set Transparency:
Bm.setpixel (x,y,color.transparent);

Set two ImageView, to upper Layer IV:
Iv.setontouchlistener (New View.ontouchlistener () {--Listen for click events
public boolean OnTouch (View v,motionevent event) {
int action=event.getaction ();
Switch (action) {
Case MOTIONEVENT.ACTION_UP:
Break
Case Motionevent.action_down:
Break
Case Motionevent.move:
int x= (int) event.getx ();
int y= (int) event.gety ();
for (int xi=x-2;xi<x+2;xi++) {
for (int yi=y-2;yi<y+2;yi++) {
Copyimage,setpixel (xi,yi,color.transparent);
}
}
Break
}
return (ture);
}
});


4. Play Music

MediaPlayer player=new MediaPlayer ();
1. Play
Player.setdatasource ("/.../. /xxx.mp3 ");

Player.setaudiostreamtype (Audiomanager.stream_music); --Set type
Player.prepare (); -------Player Ready
Player.start (); -------Start

The above way, loading from the network may be very slow. So use one-step loading:
Player.prepareasync ();
Player.setonpreparedlistener (New Onpreparedlistener () {
pulic void onprepared (MediaPlayer MP) {
Player.start (); -------set listener, play after loading is complete
}
});

Playerbutton.setenabled (flase); -----Disable the Play button
--Set the listener, when the song is finished, the button is enabled
Player.setoncompletionlistener (New Oncompletionlistener () {
public void Oncompletion (MediaPlayer MP) {
Playerbutton.setenabled (TRUE);
}
});
2. Pause
Player.pause ();
3. Replay
Player.seekto (0); -----jumps to 0 milliseconds. Unit milliseconds.
4. Stop
Player.stop ();
After---Stop, release, set empty
Player.release ();
Player=null;

5. Play Video

Method:
MediaPlayer object, with control <surfaceview/>-----can be used for video, game interface, etc.

public class Mainactivity extends Activity {
Private MediaPlayer player;
Private Surfaceview surface;
Private Surfaceholder sh;
Private Button pausebt;
private int Jindu;
@Override
protected void OnCreate (Bundle savedinstancestate) {
Super.oncreate (savedinstancestate);
Setcontentview (R.layout.activity_main);
Surface= (Surfaceview) This.findviewbyid (r.id.surface);
pausebt= (Button) This.findviewbyid (r.id.pause);
}

public void player (view view) {
Player=new MediaPlayer ();
try {
Player.setdatasource ("Http://192.168.0.129:8080/fuwuqi/123.mp4");
} catch (Exception e)
{E.printstacktrace ();}
Sh=surface.getholder ();
Sh.addcallback (New Callback () {
@Override
public void surfacechanged (surfaceholder holder, int format,
int width, int height) {
TODO auto-generated Method Stub
SYSTEM.OUT.PRINTLN ("BM");
}
@Override
public void surfacecreated (Surfaceholder holder) {
Sh=surface.getholder ();
Player.setdisplay (SH);
Player.prepareasync ();
Player.setonpreparedlistener (New Onpreparedlistener () {
@Override
public void onprepared (MediaPlayer MP) {
TODO auto-generated Method Stub
Player.seekto (Jindu);
Player.start ();
}
});
}

@Override
public void surfacedestroyed (Surfaceholder holder) {
TODO auto-generated Method Stub
Jindu=player.getcurrentposition ();
Player.stop ();
}

});
Player.setdisplay (SH);
Player.prepareasync ();
Player.setonpreparedlistener (New Onpreparedlistener () {
@Override
public void onprepared (MediaPlayer MP) {
TODO auto-generated Method Stub
Player.start ();

}
});
}
public void Pause (view view) {
if (Pausebt.gettext (). toString (). Equals ("pause")) {
if (player!=null&&player.isplaying ()) {
Player.pause ();
Pausebt.settext ("Continue");}
}else{
Player.start ();
Pausebt.settext ("pause");
}
}
public void Stop (view view) {
if (player!=null)
{player.stop ();
Player.release ();}
}
}

Some small features of Android