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POSave a canvas for a future use
 

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  1. POSave a canvas for a future use
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    <p>I have a view that extends from <code>EditText</code> that allows the user to write a text and then draw with the finger in the same view.</p> <p>What I want is to save that item for a future use, I'm thinking on when the app is destroyed and then opened the draws are removed. What I want is a way to save this drawing for the next time that the user opens the app.</p> <p>For the text I used <code>sharedPreferences</code> that save the text in the <code>onPause</code>, and for the draw I don't know how can be saved.</p> <p>I think that saving the draw as an image file not was a way to save it, but I don't know.</p> <p>EDIT:</p> <p>I tried saving the Bitmap as a jpeg and then drawing to the canvas. But it don't work, at the end, it shows the object in color black and don't allow me to draw.</p> <p>My code is the following, at the end are written the two methods that I created, but that they don't work well. They are <code>saveBitmap()</code> and <code>openBitmap()</code>:</p> <pre><code>import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; import android.content.Context; import android.graphics.*; import android.os.Environment; import android.text.Editable; import android.text.TextWatcher; import android.util.AttributeSet; import android.view.MotionEvent; import android.widget.EditText; public class DrawEditText extends EditText { private Bitmap mBitmap; private Canvas mCanvas; private Path mPath; private Paint mBitmapPaint; private Paint mPaint; private MaskFilter mEmboss; private MaskFilter mBlur; private int brush; private Boolean drawing; private int maxLines; public DrawEditText(Context c) { super(c); //This initializes all the objects mPath = new Path(); mBitmapPaint = new Paint(Paint.DITHER_FLAG); mBitmapPaint.setColor(Color.TRANSPARENT); mPaint = new Paint(); mPaint.setColor(Color.BLACK); mPaint.setStyle(Paint.Style.STROKE); mPaint.setStrokeWidth(5); mPaint.setAntiAlias(true); mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 }, 0.4f, 6, 3.5f); mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL); drawing = false; brush = -1; maxLines = 20; } public DrawEditText(Context c, AttributeSet attrs) { super(c, attrs); //This initializes all the objects mPath = new Path(); mBitmapPaint = new Paint(Paint.DITHER_FLAG); mPaint = new Paint(); mPaint.setColor(Color.BLACK); mPaint.setStyle(Paint.Style.STROKE); mPaint.setStrokeWidth(5); mPaint.setAntiAlias(true); mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 }, 0.4f, 6, 3.5f); mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL); drawing = false; brush = -1; maxLines = 20; } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888); mCanvas = new Canvas(mBitmap); } @Override protected void onDraw(Canvas canvas) { canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint); canvas.drawPath(mPath, mPaint); super.onDraw(canvas); } private float mX, mY; private static final float TOUCH_TOLERANCE = 4; private void touch_start(float x, float y) { mPath.reset(); mPath.moveTo(x, y); mX = x; mY = y; } private void touch_move(float x, float y) { float dx = Math.abs(x - mX); float dy = Math.abs(y - mY); if (dx &gt;= TOUCH_TOLERANCE || dy &gt;= TOUCH_TOLERANCE) { mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2); mX = x; mY = y; } } private void touch_up() { mPath.lineTo(mX, mY); // commit the path to our offscreen mCanvas.drawPath(mPath, mPaint); // kill this so we don't double draw mPath.reset(); } @Override public boolean onTouchEvent(MotionEvent event) { float x = event.getX(); float y = event.getY(); //This conditional makes that if not it's drawing no points are saved and no points are drawed if (drawing){ switch (event.getAction()) { case MotionEvent.ACTION_DOWN: touch_start(x, y); invalidate(); break; case MotionEvent.ACTION_MOVE: touch_move(x, y); invalidate(); break; case MotionEvent.ACTION_UP: touch_up(); invalidate(); break; } return true; } else { return super.onTouchEvent(event); } } public void changePaint(int stroke, int color){ mPaint.setColor(color); mPaint.setStrokeWidth(stroke); } public void clear(){ mCanvas.drawColor(0x00AAAAAA); mCanvas.drawColor( 0, PorterDuff.Mode.CLEAR ); setText(""); } public void changeBrush(int id){ //String[] ids={"emboss", "blur", "another"}; switch (id) { case 0: mPaint.setMaskFilter(mEmboss); brush = 0; break; case 1: mPaint.setMaskFilter(mBlur); brush = 1; break; case 2: mPaint.setMaskFilter(null); brush = -1; break; default: mPaint.setMaskFilter(null); brush = -1; break; } } public int getBrush(){ //String[] ids={"emboss", "blur", "another"}; return brush; } public void eraser(){ mPaint.setMaskFilter(null); mPaint.setColor(0x00AAAAAA); } public void setDrawing(Boolean drawing){ this.drawing = drawing; } public Boolean isDrawing(){ return drawing; } @Override protected void onFinishInflate() { super.onFinishInflate(); TextWatcher watcher = new TextWatcher() { private String text; private int beforeCursorPosition = 0; @Override public void onTextChanged(CharSequence s, int start, int before, int count) { } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { text = s.toString(); beforeCursorPosition = start; } @Override public void afterTextChanged(Editable s) { /* turning off listener */ removeTextChangedListener(this); /* handling lines limit exceed */ if (DrawEditText.this.getLineCount() &gt; maxLines) { DrawEditText.this.setText(text); DrawEditText.this.setSelection(beforeCursorPosition); } /* turning on listener */ addTextChangedListener(this); } }; this.addTextChangedListener(watcher); } @Override public int getMaxLines() { return maxLines; } @Override public void setMaxLines(int maxLines) { this.maxLines = maxLines; } public void saveBitmap(){ mCanvas.setBitmap(mBitmap); File sd = Environment.getExternalStorageDirectory(); File myDir = new File(sd + "/tweeet"); myDir.mkdirs(); File f = new File(myDir, ".drawing.jpeg"); try { if (myDir.canWrite()) { f.createNewFile(); OutputStream os = new FileOutputStream(f); mBitmap.compress(Bitmap.CompressFormat.JPEG, 100, os); os.close(); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } public void openBitmap(){ File sd = Environment.getExternalStorageDirectory(); File myDir = new File(sd + "/tweeet"); myDir.mkdirs(); File f = new File(myDir, ".drawing.jpeg"); mBitmap = BitmapFactory.decodeFile(f.getPath()); } } </code></pre>
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