Android以编程方式加载drawable并调整大小

Question

如何从InputStream(资源,文件系统)加载drawable并根据屏幕分辨率hdpi,mdpi或ldpi动态调整大小？

原始图像是hdpi,我只需要调整mdpi和ldpi的大小.

Android如何动态调整/ res中drawable的大小？

Answer 1

这很好很容易(其他答案对我不起作用),在这里找到:

  ImageView iv = (ImageView) findViewById(R.id.imageView);
  Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.picture);
  Bitmap bMapScaled = Bitmap.createScaledBitmap(bMap, newWidth, newHeight, true);
  iv.setImageBitmap(bMapScaled);

Android文档可在此处获得.

Answer 2

找到了：

  /**
   * Loads image from file system.
   * 
   * @param context the application context
   * @param filename the filename of the image
   * @param originalDensity the density of the image, it will be automatically
   * resized to the device density
   * @return image drawable or null if the image is not found or IO error occurs
   */
  public static Drawable loadImageFromFilesystem(Context context, String filename, int originalDensity) {
    Drawable drawable = null;
    InputStream is = null;

    // set options to resize the image
    Options opts = new BitmapFactory.Options();
    opts.inDensity = originalDensity;

    try {
      is = context.openFileInput(filename);
      drawable = Drawable.createFromResourceStream(context.getResources(), null, is, filename, opts);         
    } catch (Exception e) {
      // handle
    } finally {
      if (is != null) {
        try {
          is.close();
        } catch (Exception e1) {
          // log
        }
      }
    }
    return drawable;
  }

像这样使用：

loadImageFromFilesystem(context, filename, DisplayMetrics.DENSITY_MEDIUM);