如何在Android中的图片上编写文本并保存？

如何在图片上编写文本，然后将其保存在Android中？

基本上我想让用户在我的相机应用程序为他们点击的图像上写点东西。 我可以使用相机预览中的onDraw方法将其写入并显示给他们。 但是，用户点击图片后，我想写在图片上的文字，然后保存。

Answer 1

您必须实现一个允许用户在其上绘制的canvas，然后将该canvas的背景设置为该特定图像。 这只是一个猜测，但它在某处。

Answer 2

你可以把一个EditText写入它，写完之后，你先把它转换成Bitmap，如下：

Bitmap bmp = Bitmap.createBitmap(mEditText.getDrawingCache()); 

现在你可以添加创build的图像bmp到你的原始图像像这样：

调用： Bitmap combined = combineImages(bgBitmap,bmp);

 public Bitmap combineImages(Bitmap background, Bitmap foreground) { int width = 0, height = 0; Bitmap cs; width = getWindowManager().getDefaultDisplay().getWidth(); height = getWindowManager().getDefaultDisplay().getHeight(); cs = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888); Canvas comboImage = new Canvas(cs); background = Bitmap.createScaledBitmap(background, width, height, true); comboImage.drawBitmap(background, 0, 0, null); comboImage.drawBitmap(foreground, matrix, null); return cs; } 

Answer 3

让我们来帮助你..首先，你必须使用canvas来绘画。 制作一个扩展ImageView的自定义视图。 这里是onDraw函数的帮助代码..：

  @Override public void onDraw(Canvas canvas) { super.onDraw(canvas); mIcon.setBounds(0, 0, mIcon.getMinimumWidth(), mIcon.getMinimumHeight()); canvas.translate(mPosX, mPosY); canvas.scale(mScaleFactor, mScaleFactor, canvas.getWidth() * 0.5f, canvas.getWidth() * 0.5f); mIcon.draw(canvas); rect = canvas.getClipBounds(); for (Path path : listPath) { canvas.drawPath(path, paint); } } 

现在用于onTouch：

  @Override public boolean onTouchEvent(MotionEvent ev) { // Let the ScaleGestureDetector inspect all events. mScaleDetector.onTouchEvent(ev); final int action = ev.getAction(); switch (action & MotionEvent.ACTION_MASK) { case MotionEvent.ACTION_DOWN: { if (drawing) { startPoint = new Point((int) ev.getX(), (int) ev.getY()); path = new Path(); float x = ev.getX() / mScaleFactor + rect.left; float y = ev.getY() / mScaleFactor + rect.top; path.moveTo(x, y); path.lineTo(x, y); mLastTouchX_1 = x; mLastTouchY_1 = y; } else { final float x = ev.getX(); final float y = ev.getY(); mLastTouchX = x; mLastTouchY = y; mActivePointerId = ev.getPointerId(0); } break; } case MotionEvent.ACTION_MOVE: { if (drawing) { float x = ev.getX() / mScaleFactor + rect.left; float y = ev.getY() / mScaleFactor + rect.top; path.moveTo(mLastTouchX_1, mLastTouchY_1); path.lineTo(x, y); mLastTouchX_1 = x; mLastTouchY_1 = y; } else { final int pointerIndex = ev .findPointerIndex(mActivePointerId); final float x = ev.getX(pointerIndex); final float y = ev.getY(pointerIndex); // Only move if the ScaleGestureDetector isn't processing a // gesture. if (!mScaleDetector.isInProgress()) { final float dx = x - mLastTouchX; final float dy = y - mLastTouchY; mPosX += dx; mPosY += dy; invalidate(); } mLastTouchX = x; mLastTouchY = y; } break; } case MotionEvent.ACTION_UP: { path_helper_1 = new Path(); path_helper_2 = new Path(); endPoint = new Point((int) ev.getX(), (int) ev.getY()); int left, top, right, bottom; left = endPoint.x - 10; top = endPoint.y - 10; right = endPoint.x + ((endPoint.y / 2)); bottom = endPoint.x + ((endPoint.y / 2)); float dx, dy; dx = endPoint.x - startPoint.x; dy = endPoint.y - startPoint.y; dx = dx * -1; dy = dy * -1; // dx = dy = 100; double cos = 0.866 * .1; double sin = 0.500 * .1; PointF end1 = new PointF((float) (endPoint.x + (dx * cos + dy * -sin)), (float) (endPoint.y + (dx * sin + dy * cos))); PointF end2 = new PointF((float) (endPoint.x + (dx * cos + dy * sin)), (float) (endPoint.y + (dx * -sin + dy * cos))); // path.moveTo(endPoint.x, endPoint.y); // // path.lineTo(endPoint.x, endPoint.y); // // path.lineTo(end1.x, end1.y); // // path.moveTo(endPoint.x, endPoint.y); // // path.lineTo(end2.x, end2.y); // // // listPath.add(path); mActivePointerId = INVALID_POINTER_ID; break; } case MotionEvent.ACTION_CANCEL: { mActivePointerId = INVALID_POINTER_ID; break; } case MotionEvent.ACTION_POINTER_UP: { final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT; final int pointerId = ev.getPointerId(pointerIndex); if (pointerId == mActivePointerId) { // This was our active pointer going up. Choose a new // active pointer and adjust accordingly. final int newPointerIndex = pointerIndex == 0 ? 1 : 0; mLastTouchX = ev.getX(newPointerIndex); mLastTouchY = ev.getY(newPointerIndex); mActivePointerId = ev.getPointerId(newPointerIndex); } break; } } invalidate(); return true; } 

如果你想实现像这样的缩放function，也可以创build一个私有类：

  private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener { @Override public boolean onScale(ScaleGestureDetector detector) { if (zoom) { mScaleFactor *= detector.getScaleFactor(); // Don't let the object get too small or too large. mScaleFactor = Math.max(0.1f, Math.min(mScaleFactor, 5.0f)); } invalidate(); return true; } } } 

从上面的代码中获取想法，并根据您的要求进行更改。 注意上面的代码实现了绘图和缩放function。 如果你想在图片上添加文字，那么就像绘制path一样，你也可以使用canvas.drawText在canvas上绘制文本。 如果你想要多个文本轮廓图像，请创build一个数组列表。

Answer 4

在位图上添加文本：

 public Bitmap drawTextToBitmap(Context gContext, int gResId, String gText) { Resources resources = gContext.getResources(); float scale = resources.getDisplayMetrics().density; Bitmap bitmap = BitmapFactory.decodeResource(resources, gResId); android.graphics.Bitmap.Config bitmapConfig = bitmap.getConfig(); // set default bitmap config if none if(bitmapConfig == null) { bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888; } // resource bitmaps are imutable, // so we need to convert it to mutable one bitmap = bitmap.copy(bitmapConfig, true); Canvas canvas = new Canvas(bitmap); // new antialised Paint Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG); // text color - #3D3D3D paint.setColor(Color.rgb(61, 61, 61)); // text size in pixels paint.setTextSize((int) (14 * scale)); // text shadow paint.setShadowLayer(1f, 0f, 1f, Color.WHITE); // draw text to the Canvas center Rect bounds = new Rect(); paint.getTextBounds(gText, 0, gText.length(), bounds); int x = (bitmap.getWidth() - bounds.width())/2; int y = (bitmap.getHeight() + bounds.height())/2; canvas.drawText(gText, x, y, paint); return bitmap; } 

资料来源： http : //www.skoumal.net/en/android-how-draw-text-bitmap/

在位图上添加多行文本：

 public Bitmap drawMultilineTextToBitmap(Context gContext, int gResId, String gText) { // prepare canvas Resources resources = gContext.getResources(); float scale = resources.getDisplayMetrics().density; Bitmap bitmap = BitmapFactory.decodeResource(resources, gResId); android.graphics.Bitmap.Config bitmapConfig = bitmap.getConfig(); // set default bitmap config if none if(bitmapConfig == null) { bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888; } // resource bitmaps are imutable, // so we need to convert it to mutable one bitmap = bitmap.copy(bitmapConfig, true); Canvas canvas = new Canvas(bitmap); // new antialiased Paint TextPaint paint=new TextPaint(Paint.ANTI_ALIAS_FLAG); // text color - #3D3D3D paint.setColor(Color.rgb(61, 61, 61)); // text size in pixels paint.setTextSize((int) (14 * scale)); // text shadow paint.setShadowLayer(1f, 0f, 1f, Color.WHITE); // set text width to canvas width minus 16dp padding int textWidth = canvas.getWidth() - (int) (16 * scale); // init StaticLayout for text StaticLayout textLayout = new StaticLayout( gText, paint, textWidth, Layout.Alignment.ALIGN_CENTER, 1.0f, 0.0f, false); // get height of multiline text int textHeight = textLayout.getHeight(); // get position of text's top left corner float x = (bitmap.getWidth() - textWidth)/2; float y = (bitmap.getHeight() - textHeight)/2; // draw text to the Canvas center canvas.save(); canvas.translate(x, y); textLayout.draw(canvas); canvas.restore(); return bitmap; } 

资料来源： http : //www.skoumal.net/en/android-drawing-multiline-text-on-bitmap/