Android中自定义View的研究(三) -- 获得Bitmap的三种方法

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一、使用BitmapFactory解析图片

// --> 使用BitmapFactory解析图片

           public void myUseBitmapFactory(Canvas canvas){

           // 定义画笔

              Paint paint = new Paint();

           // 获取资源流

              Resources rec = getResources();

              InputStream in = rec.openRawResource(R.drawable.haha);

           // 设置图片

              Bitmap bitmap =BitmapFactory.decodeStream(in);

           // 绘制图片

              canvas.drawBitmap(bitmap, 0,20, paint);         

           }

二、使用BitmapDrawable解析图片

 

 

       // --> 使用BitmapDrawable解析图片

           public void myUseBitmapDrawable(Canvas canvas){

           // 定义画笔

              Paint paint = new Paint();

           // 获得资源

              Resources rec = getResources();

           // BitmapDrawable

              BitmapDrawable bitmapDrawable = (BitmapDrawable) rec.getDrawable(R.drawable.haha);

           // 得到Bitmap

              Bitmap bitmap = bitmapDrawable.getBitmap();

           // 在画板上绘制图片

              canvas.drawBitmap(bitmap, 20,120,paint);

           }

 

三、使用InputStream和BitmapDrawable绘制

 

       // --> 使用InputStream和BitmapDrawable解析图片

           public void myUseInputStreamandBitmapDrawable(Canvas canvas){

           // 定义画笔

              Paint paint = new Paint();

           // 获得资源

              Resources rec = getResources();

           // InputStream得到资源流

              InputStream in = rec.openRawResource(R.drawable.haha);

           // BitmapDrawable 解析数据流

              BitmapDrawable bitmapDrawable =  new BitmapDrawable(in);

           // 得到图片

              Bitmap bitmap = bitmapDrawable.getBitmap();

           // 绘制图片

              canvas.drawBitmap(bitmap, 100, 100,paint);

           }