アンドロイドのペイントでアンドゥ機能のビットマップを保存する方法は？

Question

私は元の描画線を得るために私は元に戻す機能を実装することができるアプリケーションを作っています..しかし、私はそれを行うことができません。誰もが私が感謝して感謝するためのいくつかの例を与えることができます。 ありがとう

Answer 1

ポイントのスタックを取得（ArrayListを取る）し、アクションの移動位置に基づいて。

はコンセプトhttp://www.tutorialforandroid.com/2010/11/drawing-with-canvas-in-android-undoredo.html

完璧Android add undo feature to finger paint example in api demo

Answer 2

uがUndro、やり直しでき、implemementする[方法のあまりに...

import android.app.Activity; 
import android.app.AlertDialog; 
import android.content.Context; 
import android.content.DialogInterface; 
import android.content.Intent; 
import android.graphics.Bitmap; 
import android.graphics.Paint; 
import android.graphics.Path; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.os.Handler; 
import android.os.Message; 
import android.view.MotionEvent; 
import android.view.View; 
import android.widget.Button; 
import com.almondmendoza.R; 
import com.almondmendoza.drawings.brush.Brush; 
import com.almondmendoza.drawings.brush.CircleBrush; 
import com.almondmendoza.drawings.brush.PenBrush; 

import java.io.File; 
import java.io.FileOutputStream; 
public class DrawingActivity extends Activity implements View.OnTouchListener{ 
    private DrawingSurface drawingSurface; 
    private DrawingPath currentDrawingPath; 
    private Paint currentPaint; 

    private Button redoBtn; 
    private Button undoBtn; 

    private Brush currentBrush; 

    private File APP_FILE_PATH = new File("/sdcard/TutorialForAndroidDrawings"); 




    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.drawing_activity); 

     setCurrentPaint(); 
     currentBrush = new PenBrush(); 

     drawingSurface = (DrawingSurface) findViewById(R.id.drawingSurface); 
     drawingSurface.setOnTouchListener(this); 

     redoBtn = (Button) findViewById(R.id.redoBtn); 
     undoBtn = (Button) findViewById(R.id.undoBtn); 

     redoBtn.setEnabled(false); 
     undoBtn.setEnabled(false); 
    } 

    private void setCurrentPaint(){ 
     currentPaint = new Paint(); 
     currentPaint.setDither(true); 
     currentPaint.setColor(0xFFFFFF00); 
     currentPaint.setStyle(Paint.Style.STROKE); 
     currentPaint.setStrokeJoin(Paint.Join.ROUND); 
     currentPaint.setStrokeCap(Paint.Cap.ROUND); 
     currentPaint.setStrokeWidth(3); 

    } 




    public boolean onTouch(View view, MotionEvent motionEvent) { 
     if(motionEvent.getAction() == MotionEvent.ACTION_DOWN){ 
      currentDrawingPath = new DrawingPath(); 
      currentDrawingPath.paint = currentPaint; 
      currentDrawingPath.path = new Path(); 
      currentBrush.mouseDown(currentDrawingPath.path, motionEvent.getX(), motionEvent.getY()); 


     }else if(motionEvent.getAction() == MotionEvent.ACTION_MOVE){ 
      currentBrush.mouseMove(currentDrawingPath.path, motionEvent.getX(), motionEvent.getY()); 

     }else if(motionEvent.getAction() == MotionEvent.ACTION_UP){ 
      currentBrush.mouseUp(currentDrawingPath.path, motionEvent.getX(), motionEvent.getY()); 


      drawingSurface.addDrawingPath(currentDrawingPath); 
      drawingSurface.isDrawing = true; 
      undoBtn.setEnabled(true); 
      redoBtn.setEnabled(false); 
     } 

     return true; 
    } 


    public void onClick(View view){ 
     switch (view.getId()){ 
      case R.id.colorRedBtn: 
       currentPaint = new Paint(); 
       currentPaint.setDither(true); 
       currentPaint.setColor(0xFFFF0000); 
       currentPaint.setStyle(Paint.Style.STROKE); 
       currentPaint.setStrokeJoin(Paint.Join.ROUND); 
       currentPaint.setStrokeCap(Paint.Cap.ROUND); 
       currentPaint.setStrokeWidth(3); 
      break; 
      case R.id.colorBlueBtn: 
       currentPaint = new Paint(); 
       currentPaint.setDither(true); 
       currentPaint.setColor(0xFF00FF00); 
       currentPaint.setStyle(Paint.Style.STROKE); 
       currentPaint.setStrokeJoin(Paint.Join.ROUND); 
       currentPaint.setStrokeCap(Paint.Cap.ROUND); 
       currentPaint.setStrokeWidth(3); 
      break; 
      case R.id.colorGreenBtn: 
       currentPaint = new Paint(); 
       currentPaint.setDither(true); 
       currentPaint.setColor(0xFF0000FF); 
       currentPaint.setStyle(Paint.Style.STROKE); 
       currentPaint.setStrokeJoin(Paint.Join.ROUND); 
       currentPaint.setStrokeCap(Paint.Cap.ROUND); 
       currentPaint.setStrokeWidth(3); 
      break; 

      case R.id.undoBtn: 
       drawingSurface.undo(); 
       if(drawingSurface.hasMoreUndo() == false){ 
        undoBtn.setEnabled(false); 
       } 
       redoBtn.setEnabled(true); 
      break; 

      case R.id.redoBtn: 
       drawingSurface.redo(); 
       if(drawingSurface.hasMoreRedo() == false){ 
        redoBtn.setEnabled(false); 
       } 

       undoBtn.setEnabled(true); 
      break; 
      case R.id.saveBtn: 
       final Activity currentActivity = this; 
       Handler saveHandler = new Handler(){ 
        @Override 
        public void handleMessage(Message msg) { 
         final AlertDialog alertDialog = new AlertDialog.Builder(currentActivity).create(); 
         alertDialog.setTitle("Saved 1"); 
         alertDialog.setMessage("Your drawing had been saved :)"); 
         alertDialog.setButton("OK", new DialogInterface.OnClickListener() { 
          public void onClick(DialogInterface dialog, int which) { 
           return; 
          } 
         }); 
         alertDialog.show(); 
        } 
       } ; 
       new ExportBitmapToFile(this,saveHandler, drawingSurface.getBitmap()).execute(); 
      break; 
      case R.id.circleBtn: 
       currentBrush = new CircleBrush(); 
      break; 
      case R.id.pathBtn: 
       currentBrush = new PenBrush(); 
      break; 
     } 
    } 


    private class ExportBitmapToFile extends AsyncTask<Intent,Void,Boolean> { 
     private Context mContext; 
     private Handler mHandler; 
     private Bitmap nBitmap; 

     public ExportBitmapToFile(Context context,Handler handler,Bitmap bitmap) { 
      mContext = context; 
      nBitmap = bitmap; 
      mHandler = handler; 
     } 

     @Override 
     protected Boolean doInBackground(Intent... arg0) { 
      try { 
       if (!APP_FILE_PATH.exists()) { 
        APP_FILE_PATH.mkdirs(); 
       } 

       final FileOutputStream out = new FileOutputStream(new File(APP_FILE_PATH + "/myAwesomeDrawing.png")); 
       nBitmap.compress(Bitmap.CompressFormat.PNG, 90, out); 
       out.flush(); 
       out.close(); 
       return true; 
      }catch (Exception e) { 
       e.printStackTrace(); 
      } 
      //mHandler.post(completeRunnable); 
      return false; 
     } 


     @Override 
     protected void onPostExecute(Boolean bool) { 
      super.onPostExecute(bool); 
      if (bool){ 
       mHandler.sendEmptyMessage(1); 
      } 
     } 
    } 
}