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Android Picasso load image to Bitmap variable cropping it to square

I need to load some images from URI to Bitmap variables and perform some operation with them togheter. I need the bitmaps to be squared images with fixes size, scaled down and cropped. By now I use this code:
return Picasso.with(c).load(imageUri).resize(size, size).get();
but, obviously, the image will be resized without keep its aspect ratio.
I want to resize the image with these requirements:
the smaller dimension (width or height) should be equals to size
the greater dimension should be cropped to size, keep image centered

The key is using centerInside after resize. See link
Picasso.with(c).load(imageUri).resize(size, size).centerInside().get()

set your imageview height and width fix inside xml and then set image to imageview like
Picasso.with(YourActivityName.this)
.load(imageUri)
.into(imageview_id);

how to scale down the image from drawable folder in android?

I am setting a imgage in an ImageView. I want to scale down the image size without reducing the imageview size. Please guide me step by step.

Use scaleType parameter for your imageviews and set the value to centerFit or centerCrop. More here: http://developer.android.com/reference/android/widget/ImageView.ScaleType.html

Taken from this link: source
You should also see android:adjustViewBounds to make the ImageView resize itself to fit the rescaled image. For example, if you have a rectangular image in what would normally be a square ImageView, adjustViewBounds=true will make it resize the ImageView to be rectangular as well. This then affects how other Views are laid out around the ImageView.

How to get width of what image really occupies on the ImageView android

I have an activity which only has an ImageView on it. I'm setting an image bitmap for this view that is much taller than wider. So, for example, my activity has 720x950 and my image is 918x2077.
When I add the image in the imageView, both side parts of imageView stays white (read: no image in there).
If I call mImage.getWidth() it returns me the width of the entire imageView of 720 (which is the activity wide).
I would like to get the width of the image in specific, not of the view.. is that possible?

It sounds like the aspect ratio of your image is being kept. You want to know how much width the image is actually occupying.
You can calculate it!
if your bitmap is 918x2077 and your window size is 720x950, then to calculate your width, simply do:
(950/2077) * 918 = 419.8844...
Hope this helps :)

Image View doesn't show clear image defined in xml

In my code I want to set a default image for my imageview. All my images are of 174px X 174px. So, I want the default image to be same size. This is my xml for image view
//....code
<ImageView
android:id="#+id/ivCover"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:contentDescription="Default Image"
android:src="#drawable/default_cover" />
//....some other code
Now, my default_cover.jpg is also 174px X 174px. But it shows a smaller image. I've tried all
android:scaleType="centerInside"
android:scaleType="center"
android:scaleType="matrix"
even when most of them were senseless for me but still I tried all of 'em & none of them works. Then I specified the height & width of image by specifying
android:layout_width="174px"
android:layout_height="174px"
(I know using dp is better than px but because this image size is fixed & I was just testing it). So it shows
[default image]
while when loaded from an external url using
Bitmap bitmap = BitmapFactory.decodeStream((InputStream) new URL(url_source_for_image).getContent());
ivCover.setImageBitmap(bitmap);
desired image
[]
The two pictures may not look very different here but the difference is very clear on my android device. And please don't say that I didn't try other solutions..
Here is a list of links of so itself..
ImageView fit without stretching the image
Fit image into ImageView, keep aspect ratio and then resize ImageView to image dimensions?
ImageView one dimension to fit free space and second evaluate to keep aspect ration
Resizing ImageView to fit to aspect ratio
Maximum width and height for ImageView in Android
Image in ImageView is stretched - Android
Android: How to prevent image from being scaled in ImageView or ImageButton?

Sounds like the answer is to use drawable-nodpi. For future reference, if you have the same named image in both the ldpi/hdpi/etc and in no-dpi, I think the no-dpi one will be ignored.

Behaviour of ImageView when scaled

I do some operations with my Views that scale then trough:
imageView.setScaleX(2);
imageView.setScaleY(2);
On that ImageView I put a image that is two times greater than it, as expected when the scale is 1, the Bitmap is scaled down to the view size, my question is:
When the view is scaled up, the portion of the bitmap I see is the original image or the scaled-down image scaled up.
The difference is that if a tiny image is scaled up we lost contrast on letters, if it's the original image it wont.

When you scale an image up you're loosing quality. In you're case, you're doubling the width and height therefore, for each pixel you get 4 pixels assigned to it. The extra 3 pixels won't give you the quality you wanted.
If you want to go back to the original size you should decode the source again. This way you'll get the quality you're looking for.