利用canvas和bitmap如何对图片缩放到适应屏幕大小？

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我是靠谱客的博主明亮鸭子，这篇文章主要介绍利用canvas和bitmap如何对图片缩放到适应屏幕大小？，现在分享给大家，希望可以做个参考。

创建你自己想要大小的 bitmap

public static Bitmap resizeBitmap(Bitmap bitmap, int w, int h) {
      if (bitmap != null) {
         int width = bitmap.getWidth();
         int height = bitmap.getHeight();
         int newWidth = w;
         int newHeight = h;
         float scaleWidth = ((float) newWidth) / width;
         float scaleHeight = ((float) newHeight) / height;
         Matrix matrix = new Matrix();
         matrix.postScale(scaleWidth, scaleHeight);
         Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0, width,
                  height, matrix, true);
         return resizedBitmap;
      } else {
         return null;
      }
}
public static Bitmap resizeBitmap(String path,int  width,int height){
      BitmapFactory.Options options = new BitmapFactory.Options();
         options.inJustDecodeBounds = true;
         options.outWidth = width;
         options.outHeight = height;

      Bitmap bmp = BitmapFactory.decodeFile(path, options);
      options.inSampleSize = options.outWidth / height;
options.inJustDecodeBounds = false;
   bmp = BitmapFactory.decodeFile(path, options);
return bmp;
}

转载于:https://blog.51cto.com/8988940/1574099