import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
/**
* 处理背景图片的一些工具,如放大 缩小...
*/
public class BgUtil {
/**
* 使背景图片适应手机屏幕分辨率
*
* @param context 上下文环境
* @param screenWidth 手机屏幕宽度
* @param screenHeight 手机屏幕高度
* @param resId 背景图片资源ID
* @return 返回一个新的适应手机屏幕分辨率的图片
*/
public static Bitmap getSuitableBg(Context context, int screenWidth, int screenHeight, int resId) {
Bitmap bg = BitmapFactory.decodeResource(context.getResources(), resId);
int bgWidth = bg.getWidth();
int bgHeight = bg.getHeight();
float scaleWidth = (float) screenWidth / bgWidth;
float scaleHeight = (float) screenHeight / bgHeight;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
Bitmap newBg = Bitmap.createBitmap(bg, 0, 0, bgWidth, bgHeight, matrix, true);
return newBg;
}
}