Android怎样修改图片

首先来看一看怎么获取Bitmap， 有两种方法：

1.

Resources r = this.getContext().getResources();  
Inputstream is = r.openRawResource(R.drawable.icon);  
BitmapDrawable  bmpDraw = new BitmapDrawable(is);  
Bitmap bmp = bmpDraw.getBitmap();  

 

2.

InputStream is = getResources().openRawResource(R.drawable.icon);    
Bitmap mBitmap = BitmapFactory.decodeStream(is);    
Paint mPaint = new Paint();    
canvas.drawBitmap(mBitmap, 40, 40, mPaint);   

 

ok, 已经得到了Bitmap对象，那么怎么修改这个bitmap，比如在这个Bitmap上写字。看代码：

//使用Bitmap的静态方法，只有这个方法可以创建一个mutable的Bitmap
Bitmap newBitmap = Bitmap.createBitmap(dw, dh, Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
//将原先获取的Bitmap画在Canvas上
canvas.drawBitmap(bitmapOld, left, top, paint);
canvas.drawText(numberText, mNumberX, mNumberY, numberPain);