ImageView fit width crop bottom

Question

I want to scale image to fit screen width and keep aspect ratio

1. if image height is smaller than screen height. I want to strength it.
2. if image height is larger than screen height. I want to crop it.

I google for it but set scaleType to FitXY & AdjustViewInBounds doesn't work.

I test with 50x50 image and it's not working

// Use createScaledBitmap will cause OOM, so I set image to imageView first.
ImageView image= (ImageView) mPageView.findViewById(R.id.image);

// Set image to get IntrinsicWidth & IntrinsicHeight
image.setImageResource(imageDrawable);

// Change scale type to matrix
image.setScaleType(ImageView.ScaleType.MATRIX);

// Calculate bottom crop matrix
Matrix matrix = getBottomCropMatrix(mContext, image.getDrawable().getIntrinsicWidth(), image.getDrawable().getIntrinsicHeight());

// Set matrixx
image.setImageMatrix(matrix);
// Redraw image
image_image.invalidate();

And my matrix use following method

Matrix matrix = new Matrix();

// Get screen size
int screenWidth = context.getResources().getDisplayMetrics().widthPixels;
int screenHeight = context.getResources().getDisplayMetrics().heightPixels;

// Get scale to match parent
float scaleWidthRatio = screenWidth / imageWidth;
float scaleHeightRatio = screenHeight / imageHeight;

// screenHeight multi by width scale to get scaled image height
float scaledImageHeight = imageHeight * scaleWidthRatio;

// If scaledImageHeight < screenHeight, set scale to scaleHeightRatio to fit screen
// If scaledImageHeight >= screenHeight, use width scale as height scale
if (scaledImageHeight >= screenHeight) {
    scaleHeightRatio = scaleWidthRatio;
}

matrix.setScale(scaleWidthRatio, scaleHeightRatio);

I don't know where I am wrong. It just leave some blank at the bottom.

========

Update. I found out the problem. My matrix is right. The blank at the bottom is soft navigation bar. Use following method will get wrong value.

getResources().getDisplayMetrics()

Change it to

    DisplayMetrics displaymetrics = new DisplayMetrics();
    WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    windowManager.getDefaultDisplay().getRealMetrics(displaymetrics);
    int screenWidth = displaymetrics.widthPixels;
    int screenHeight = displaymetrics.heightPixels;

and it works!

Answer 1

Update. I found out the problem. My matrix is right. The blank at the bottom is soft navigation bar. Use following method will get wrong value.

getResources().getDisplayMetrics()

Change it to

    DisplayMetrics displaymetrics = new DisplayMetrics();
    WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    windowManager.getDefaultDisplay().getRealMetrics(displaymetrics);
    int screenWidth = displaymetrics.widthPixels;
    int screenHeight = displaymetrics.heightPixels;

and it works!