Question

我正在使用搜索栏来缩放图像。图像缩放到一个特定大小，无论您采用搜索条还是缩放一次，下次更改搜索条的进度时图像保持相同的更改大小。我希望随着搜索栏进度的增加或减少而动态扩展它。

Seekbar代码段

seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

        @Override
        public void onStopTrackingTouch(SeekBar arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onStartTrackingTouch(SeekBar arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onProgressChanged(SeekBar seekBar, int progresValue,
                boolean fromUser) {
            // TODO Auto-generated method stub
            Log.i("Test", "Progress value = " + Integer.toString(progresValue));
            Log.i("Test", "Image width = " + Integer.toString(width));
            Log.i("Test", "Image height = " + Integer.toString(height));

            scaleImage(image, width, height);
        }
    });

缩放图像的功能

public void scaleImage(Bitmap bitmap, int w, int h) {

    // Get current dimensions AND the desired bounding box
    int bounding = dpToPx(150);
    Log.i("Test", "original width = " + Integer.toString(w));
    Log.i("Test", "original height = " + Integer.toString(h));
    Log.i("Test", "bounding = " + Integer.toString(bounding));

    // Determine how much to scale: the dimension requiring less scaling is
    // closer to the its side. This way the image always stays inside your
    // bounding box AND either x/y axis touches it.
    float xScale = ((float) bounding) / w;
    float yScale = ((float) bounding) / h;
    float scale = (xScale <= yScale) ? xScale : yScale;
    Log.i("Test", "xScale = " + Float.toString(xScale));
    Log.i("Test", "yScale = " + Float.toString(yScale));
    Log.i("Test", "scale = " + Float.toString(scale));

    // Create a matrix for the scaling and add the scaling data
    Matrix matrix = new Matrix();
    matrix.postScale(scale, scale);

    // Create a new bitmap and convert it to a format understood by the
    // ImageView
    Bitmap scaledBitmap = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix,
            true);
    sWidth = scaledBitmap.getWidth(); // re-use
    sHeight = scaledBitmap.getHeight(); // re-use
    @SuppressWarnings("deprecation")
    BitmapDrawable result = new BitmapDrawable(scaledBitmap);
    Log.i("Test", "scaled width = " + Integer.toString(sWidth));
    Log.i("Test", "scaled height = " + Integer.toString(sHeight));
    qrImage.setImageDrawable(result);

}

制作边界框的功能

private int dpToPx(int dp) {
    float density = getActivity().getApplicationContext().getResources()
            .getDisplayMetrics().density;
    return Math.round((float) dp * density);
}

Answer 1

使用以下代码使用搜索栏调整图片大小

public class MyActivity extends Activity {

private static final int WIDTH_SCALE_RATIO = 10;
private static final int HEIGHT_SCALE_RATIO = 10;
private int previousProcess = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    final ImageView img = (ImageView) findViewById(R.id.img);
    ((SeekBar) findViewById(R.id.seekBar))
            .setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
                @Override
                public void onStopTrackingTouch(SeekBar arg0) {
                }

                @Override
                public void onStartTrackingTouch(SeekBar arg0) {
                }

                @Override
                public void onProgressChanged(SeekBar seekBar,
                        int progresValue, boolean fromUser) {
                    int diff = progresValue - previousProcess;
                    scaleImage(img, diff);
                    previousProcess = progresValue;
                }
            });
}

public void scaleImage(ImageView img, int scale) {
    Bitmap bitmap = ((BitmapDrawable) img.getDrawable()).getBitmap();
    float width = bitmap.getWidth();
    float height = bitmap.getHeight();
    width += scale * WIDTH_SCALE_RATIO;
    height += scale * HEIGHT_SCALE_RATIO;
    bitmap = Bitmap.createScaledBitmap(bitmap, (int) width, (int) height,
            true);
    img.setImageBitmap(bitmap);
}
}

通过Seekbar缩放位图

1 个答案: