安卓几种常用函数

1.保存图片文件到SD卡

	private InputStream Bitmap2IS(Bitmap bm) {

		ByteArrayOutputStream baos = new ByteArrayOutputStream();

		bm.compress(Bitmap.CompressFormat.PNG, 100, baos);

		InputStream sbs = new ByteArrayInputStream(baos.toByteArray());

		return sbs;



	}



	public void onClick_SaveImageToSDCard(View view) {

		try {

			FileOutputStream fos = new FileOutputStream(ALBUM_PATH

					+ "/QRcode.png");

			// InputStream is = getResources().getAssets().open("image.jpg");

			InputStream is = Bitmap2IS(bit);

			byte[] buf = new byte[4096];

			int count = 0;

			while ((count = is.read(buf)) >= 0) {

				fos.write(buf, 0, count);

			}

			fos.close();

			is.close();

			/*

			 * byte[] buffer = new byte[8192]; int count = 0; while((count =

			 * is.read(buffer)) >= 0){ fos.write(buffer,0,count); } fos.close();

			 * is.close();

			 */

			Toast.makeText(this, "写入成功！", Toast.LENGTH_LONG).show();

		} catch (Exception e) {

			// TODO: handle exception

			Toast.makeText(this, e.getMessage(), Toast.LENGTH_LONG).show();

		}

	}