Android programming to achieve hand-painted and saved as a picture of the method (with demo source download) _android

This article describes the Android programming implementation of hand-painted and saved as a picture of the method. Share to everyone for your reference, specific as follows:

Run Effect Chart preview:

Should be yzuo_08 required to do this demo, with the previous tablet demo is different from the canvas can be saved as a picture of the content.

Attach Key code:

Mainview.java

Package com.tszy.views; 
Import Java.io.File; 
Import java.io.FileNotFoundException; 
Import Java.io.FileOutputStream; 
Import java.io.IOException; 
Import Android.content.Context; 
Import Android.graphics.Bitmap; 
Import Android.graphics.Bitmap.CompressFormat; 
Import Android.graphics.Bitmap.Config; 
Import Android.graphics.Canvas; 
Import Android.graphics.Color; 
Import Android.graphics.Paint; 
Import Android.graphics.Path; 
Import Android.util.AttributeSet; 
Import android.view.MotionEvent; 
Import Android.view.View; 
 public class Mainview extends View {private Paint Paint; 
 Private Canvas Cachecanvas; 
 Private Bitmap Cachebbitmap; 
 private path Path; 
 private int CLR_BG, CLR_FG; 
  Public Mainview (context, AttributeSet attrs) {Super (context, attrs); 
  CLR_BG = Color.White; 
  CLR_FG = Color.cyan; 
  Paint = new paint (); Paint.setantialias (TRUE); Anti-aliasing paint.setstrokewidth (3); Line width paint.setstyle (Paint.Style.STROKE); Draw Contour Paint.setcolor (CLR_FG); Color path = new Path (); 
  Create a bitmap of the screen size, as a buffer Cachebbitmap = Bitmap.createbitmap (config.argb_8888); 
  Cachecanvas = new Canvas (CACHEBBITMAP); 
 Cachecanvas.drawcolor (CLR_BG); 
 Public Mainview {Super (context); 
  } @Override protected void OnDraw (Canvas Canvas) {canvas.drawcolor (CLR_BG); 
  Draw the previous one, otherwise incoherent canvas.drawbitmap (cachebbitmap, 0, 0, NULL);
 Canvas.drawpath (path, paint); 
  /** * Empty canvas/public void Clear () {path.reset (); 
  Cachecanvas.drawcolor (CLR_BG); 
 Invalidate (); /** * Saves the contents of the canvas to the file * @param filename * @throws filenotfoundexception */public void SaveToFile (String fil 
  ename) throws FileNotFoundException {file F = new file (filename); if (f.exists ()) throw new RuntimeException ("file: + filename +" already exists!) 
  "); 
  FileOutputStream fos = new FileOutputStream (new File (filename)); 
  Compress the bitmap into other formats of the picture data cachebbitmap.compress (compressformat.png, FOS); try {fos.clOSE (); 
  catch (IOException e) {//TODO auto-generated catch block E.printstacktrace (); 
 } private float cur_x, cur_y; 
 Private Boolean ismoving; @Override public boolean ontouchevent (Motionevent event) {//TODO auto-generated method stub float x = Event.getx 
  (); 
  Float y = event.gety (); 
    Switch (event.getaction ()) {case Motionevent.action_down: {cur_x = x; 
    cur_y = y; 
    Path.moveto (cur_x, cur_y); 
    Ismoving = true; 
   Break 
    Case Motionevent.action_move: {if (!ismoving) break; 
    Two times curve way to draw path.quadto (cur_x, cur_y, x, y); 
    The following method looks like the above//Path.lineto (x, y); 
    cur_x = x; 
    cur_y = y; 
   Break 
    Case MOTIONEVENT.ACTION_UP: {//mouse bounce Save last State cachecanvas.drawpath (path, paint); 
    Path.reset (); 
    Ismoving = false; 
   Break 
  }//Notification Refresh interface invalidate (); 
 return true;

 } 
}

Activity code:

@Override public void OnClick (View v) {//TODO auto-generated a stub switch (V.getid ()) {case R.id.iv_b 
    Tn_clear:view.clear (); 
   Break Case R.id.iv_btn_save: {try {String sdstate = environment.getexternalstoragestate ()//To determine if SD card exists//check Check if the SD card is available if (!sdstate.equals (Android.os.Environment.MEDIA_MOUNTED)) {Toast.maketext (this, "SD card is not ready!") 
      ", Toast.length_short). Show (); 
     Break 
     //Get the system picture storage path, File path = Environment.getexternalstoragepublicdirectory (environment.directory_pictures); 
     Make sure the Pictures directory exists. 
     Path.mkdirs (); 
     Generates a picture name based on the current time Calendar C = calendar.getinstance (); String name = "" + c.get (calendar.year) + c.get (calendar.month) + c.get (calendar.day_of_month) + c.get (Cal Endar. 
     Hour_of_day) + c.get (calendar.minute) + c.get (Calendar.second) + ". png"; 
 Synthetic full path, note/delimiter string = Path.getpath () + "/" + name;    View.savetofile (string); Toast.maketext (This, "Save success!) 
    \ n file is guaranteed to exist: "+ String, Toast.length_long. Show (); catch (FileNotFoundException e) {Toast.maketext (this, "Save failed!) 
    \ n "+ E, Toast.length_long). Show (); 
   } break;

 } 
  } 
}

No difficulty, mainly will be bitmap to PNG pictures there, find a Canvas not directly or indirectly save the method, just here I use double buffering, another piece of canvas content bitmap created, it is natural to think of this canvas bitmap saved as a file.

Then look at the Bitmap there is a compress (compressformat format, int quality,outputstream stream) method, it is obvious that the output of the file passed to this method is OK

@Override public void OnClick (View v) {//TODO auto-generated a stub switch (V.getid ()) {case R.id.iv_b 
    Tn_clear:view.clear (); 
   Break Case R.id.iv_btn_save: {try {String sdstate = environment.getexternalstoragestate ()//To determine if SD card exists//check Check if the SD card is available if (!sdstate.equals (Android.os.Environment.MEDIA_MOUNTED)) {Toast.maketext (this, "SD card is not ready!") 
      ", Toast.length_short). Show (); 
     Break 
     //Get the system picture storage path, File path = Environment.getexternalstoragepublicdirectory (environment.directory_pictures); 
     Make sure the Pictures directory exists. 
     Path.mkdirs (); 
     Generates a picture name based on the current time Calendar C = calendar.getinstance (); String name = "" + c.get (calendar.year) + c.get (calendar.month) + c.get (calendar.day_of_month) + c.get (Cal Endar. 
     Hour_of_day) + c.get (calendar.minute) + c.get (Calendar.second) + ". png"; 
  Synthetic full path, note/delimiter string = Path.getpath () + "/" + name;   View.savetofile (string); Toast.maketext (This, "Save success!) 
    \ n file is guaranteed to exist: "+ String, Toast.length_long. Show (); catch (FileNotFoundException e) {Toast.maketext (this, "Save failed!) 
    \ n "+ E, Toast.length_long). Show (); 
   } break;

 } 
  } 
}

Full instance code click here to download the site.

I hope this article will help you with the Android program.