Scale images to completely fit the screen - android

I'm using the HorizontalScrollView and I want to put images inside it but images will be larger than the screen and makes users scroll horizontally while I'm using setScaleType(ImageView.ScaleType.CENTER_CROP) or other attributes.
How can I have images completely fit the screen? I prefer to use XML attributes if it is possible.
activity_main.xml
<HorizontalScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<LinearLayout
android:id="#+id/main"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
</LinearLayout>
MainActivity.java
ImageView image = new ImageView(this);
image.setImageResource(getResources().getIdentifier('file_name', "drawable", getPackageName()));
image.setAdjustViewBounds(true);
image.setScaleType(ImageView.ScaleType.CENTER_CROP);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
image.setLayoutParams(layoutParams);
parent.addView(image);

You can use this xml property into your ImageView,
android:scaleType="fitXY"
Or use this dynamic code snippet to fit the ImageView accordingly the screen ratio,
private void scaleImage(ImageView view, int boundBoxInDp)
{
// Get the ImageView and its bitmap
Drawable drawing = view.getDrawable();
Bitmap bitmap = ((BitmapDrawable)drawing).getBitmap();
// Get current dimensions
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// 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) boundBoxInDp) / width;
float yScale = ((float) boundBoxInDp) / height;
float scale = (xScale <= yScale) ? xScale : yScale;
// 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, width, height, matrix, true);
BitmapDrawable result = new BitmapDrawable(scaledBitmap);
width = scaledBitmap.getWidth();
height = scaledBitmap.getHeight();
// Apply the scaled bitmap
view.setImageDrawable(result);
// Now change ImageView's dimensions to match the scaled image
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) view.getLayoutParams();
params.width = width;
params.height = height;
view.setLayoutParams(params);
}
private int dpToPx(int dp)
{
float density = getApplicationContext().getResources().getDisplayMetrics().density;
return Math.round((float)dp * density);
}
And sample code for testing:
ImageView image = new ImageView(this);
scaleImage(image , 250); // in dp
Here's the output,
Before,
After,
Source: Scale image into ImageView, then resize ImageView to match the image

Related

Android ImageView not scaling to screen width

I am using following function to scale any image to screen width:
DisplayMetrics metrics = new DisplayMetrics();
((Activity)context)
.getWindowManager()
.getDefaultDisplay()
.getMetrics(metrics);
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// Calculate the ratio between height and width of Original Image
float ratio = (float) height / (float) width;
int newWidth = metrics.widthPixels; // This will be equal to screen width
float newHeight = newWidth * ratio; // This will be according to the ratio calulated
// calculate the scale
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = newHeight / height;
// create a matrix for the manipulation
Matrix matrix = new Matrix();
// resize the bit map
matrix.postScale(scaleWidth, scaleHeight);
// recreate the new Bitmap
Bitmap resizedBitmap
= Bitmap.createBitmap(
bitmap, 0, 0,
width, height,
matrix, true
);
// make a Drawable from Bitmap to allow to set the BitMap
// to the ImageView, ImageButton or what ever
return new BitmapDrawable(resizedBitmap);
After putting some checks, the values are, metrics.widthPixels=540 and the width of new Bitmap is also 540. That means Bitmap or Imageview should use full screen width. Instead, the resulting imageviews are short of full screen width. I am including a screenshot:
As you can see in the image, the remaining blank part of the screen is shown in Black Color.
The code for creating ImageView is:
ImageView imageBanner = new ImageView(context);
imageBanner.setLayoutParams(new
LinearLayout.LayoutParams(
Globals.wrapContent,
Globals.wrapContent));
imageBanner.setBackgroundResource(R.drawable.imv_banner);
new SyncImage(context, imageBanner, urlImage).execute();
Globals.wrapContent are the explicit constants which contain same values for standard Layout Params, so don't think them as different.
SyncImage the Async Class used to download and show image in ImageView.
Please provide a solution to scale the image to full screen width and image should retain its original dimension ratio.
Thank You
Ram Ram
Set Width of imageView to MatchParent instead of WrapContent and calculate height to maintain the aspect ratio of the image. Try following code to resize the image:
Display display = getActivity().getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int newWidth = size.x;
//Get actual width and height of image
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// Calculate the ratio between height and width of Original Image
float ratio = (float) height / (float) width;
float scale = getApplicationContext().getResources().getDisplayMetrics().density;
int newHeight = (int) (width * ratio)/scale;
return Bitmap.createScaledBitmap(bitmap, newWidth, newHeight, true);

Why are images larger than the set size not being scaled down

I work out the width and height of my fragment and scale its image to a specific percentage of that fragment. This works for images that need to be scaled up to meet that size but larger images seem to ignore the scales (i think they shrink a bit but not to corretc size).
I get my imahes via http asyncTask call then on onPostexecute set the imageView control src and scale the imageView. Work for smaller images, not larger ones.
The larger image is 10kb, smaller is 1kb.
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
if (result != null) {
int width = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PT, 35, getContext().getResources().getDisplayMetrics());
int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PT, 35, getContext().getResources().getDisplayMetrics());
bmImage.setMinimumWidth(width);
bmImage.setMinimumHeight(height);
bmImage.setMaxWidth(width);
bmImage.setMaxHeight(height);
}
I see the dimensions being calc'c correctly and afterwards set correctly in the imageView )(minimum and maxheight) but the mDrawable attr is big so perhaps this is an indicator of worng attr being set?
https://argillander.wordpress.com/2011/11/24/scale-image-into-imageview-then-resize-imageview-to-match-the-image/
private void scaleImage(ImageView view, int boundBoxInDp)
{
// Get the ImageView and its bitmap
Drawable drawing = view.getDrawable();
Bitmap bitmap = ((BitmapDrawable)drawing).getBitmap();
// Get current dimensions
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// 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) boundBoxInDp) / width;
float yScale = ((float) boundBoxInDp) / height;
float scale = (xScale <= yScale) ? xScale : yScale;
// 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, width, height, matrix, true);
BitmapDrawable result = new BitmapDrawable(scaledBitmap);
width = scaledBitmap.getWidth();
height = scaledBitmap.getHeight();
// Apply the scaled bitmap
view.setImageDrawable(result);
// Now change ImageView's dimensions to match the scaled image
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) view.getLayoutParams();
params.width = width;
params.height = height;
view.setLayoutParams(params);
}

Size incoming image into a Android layout

How can I fit any size image coming in from a http request into a ImageView with the size of 100x100.
android:layout_width="100dp"
android:layout_height="100dp"
I want to avoid loosing accuracy and I'd like to see the exact same image but in 100x100 size.
I have tried with Bitmap.createScaledBitmap(bitmap, 100, 100, true); but failed.
What are the correct steps doing this?
Check out this link :
Fit image into ImageView, keep aspect ratio and then resize ImageView to image dimensions?
And ImageView that is a fixed size, regardless of image size
Try
android:scaleType="fitXY"
for larger images
Take a look at this:
"This cannot be done in xml only. It is not possible to scale both the image and the ImageView so that image's one dimension would always be 100dp and the ImageView would have the same dimensions as the image.
This code scales Drawable of an ImageView to stay in a square like 100dp x 100dp with one dimension exactly 100dp and keeping the aspect ratio. Then the ImageView is resized to match the dimensions of the scaled image. The code is used in an activity. I tested it via button click handler.
private void scaleImage()
{
// Get the ImageView and its bitmap
ImageView view = (ImageView) findViewById(R.id.image_box);
Drawable drawing = view.getDrawable();
if (drawing == null) {
return; // Checking for null & return, as suggested in comments
}
Bitmap bitmap = ((BitmapDrawable)drawing).getBitmap();
// Get current dimensions AND the desired bounding box
int width = bitmap.getWidth();
int height = bitmap.getHeight();
int bounding = dpToPx(250);
Log.i("Test", "original width = " + Integer.toString(width));
Log.i("Test", "original height = " + Integer.toString(height));
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) / width;
float yScale = ((float) bounding) / height;
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, width, height, matrix, true);
width = scaledBitmap.getWidth(); // re-use
height = scaledBitmap.getHeight(); // re-use
BitmapDrawable result = new BitmapDrawable(scaledBitmap);
Log.i("Test", "scaled width = " + Integer.toString(width));
Log.i("Test", "scaled height = " + Integer.toString(height));
// Apply the scaled bitmap
view.setImageDrawable(result);
// Now change ImageView's dimensions to match the scaled image
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) view.getLayoutParams();
params.width = width;
params.height = height;
view.setLayoutParams(params);
Log.i("Test", "done");
}
private int dpToPx(int dp)
{
float density = getApplicationContext().getResources().getDisplayMetrics().density;
return Math.round((float)dp * density);
}
The xml code for the ImageView:
<ImageView a:id="#+id/image_box"
a:background="#ff0000"
a:src="#drawable/star"
a:layout_width="wrap_content"
a:layout_height="wrap_content"
a:layout_marginTop="20dp"
a:layout_gravity="center_horizontal"/>"
source

Android: how to set the height/width of the src image of a ImageButton?

Android: how to set the height/width of the image(src image intead of the background) of a ImageButton?
I want to set the height/width of the top level image(not the background) image, the size of image should be customized instead of fullfill the button automatically
You can just Use the scaleType attribute of ImageButton.
Set it to fitXY or fitCenter or anything else according to your need.
like this
<ImageButton
android:id="#+id/imageButton"
android:layout_width="100dp"
android:layout_height="100dp"
android:scaleType="fitCenter"
android:src="#drawable/some_image">
</ImageButton>
You can use Bitmap.createScaledBitmap to scale the image to the size you want.
Bitmap image = ... //load image from your source
image = Bitmap.createScaledBitmap(image, desiredHeight, desiredWidth, true);
xml
<ImageButton
android:id="#+id/picture_id"
android:layout_width="10dp" //here width with unit. 5 dp exemple
android:layout_height="3dp" //here height with unit. 3 dp exemple
android:src="#drawable/picture_name"
/>
EDIT: (java code)
// load the origial BitMap (500 x 500 px)
Bitmap bitmapOrg = BitmapFactory.decodeResource(getResources(),
R.drawable.android);
int width = bitmapOrg.width();
int height = bitmapOrg.height();
int newWidth = 200;
int newHeight = 200;
// calculate the scale - in this case = 0.4f
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// create a matrix for the manipulation
Matrix matrix = new Matrix();
// resize the bit map
matrix.postScale(scaleWidth, scaleHeight);
// rotate the Bitmap
matrix.postRotate(45);
// recreate the new Bitmap
Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0,
width, height, matrix, true);
// make a Drawable from Bitmap to allow to set the BitMap
// to the ImageView, ImageButton or what ever
BitmapDrawable bmd = new BitmapDrawable(resizedBitmap);
ImageView imageView = new ImageView(this);
// set the Drawable on the ImageView
imageView.setImageDrawable(bmd);
// center the Image
imageView.setScaleType(ScaleType.CENTER);
// add ImageView to the Layout
linLayout.addView(imageView,
new LinearLayout.LayoutParams(
LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT
)
);
I had same problem... change the size of 'src' image of image button(not the size of button just image only).
what i did--
I moved those '.png' file from 'drawable' folder to 'drawable-hdpi' folder.
weird... but it worked.
thanks,
set padding and scaletype to centerInside
Padding will help you customize the source image to provide the required height and width.
<ImageButton
android:layout_width="50dp"
android:layout_height="50dp"
android:src="#drawable/location"
android:padding="10dp"
android:scaleType="centerInside"
android:background="#drawable/blue_circle_border"/>

Android: Resizing and scaling a part of the image

Given an image, I want to be able to scale only a part of that image. Say, I want to expand half of the image so that, that half takes up the whole space.
How is this possible?
Will ImageView fitXY work because I thought it'll work only for the whole original image.
#Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); LinearLayout linearLayout = new LinearLayout(this);
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
int width = bitmap.getWidth();
int height = bitmap.getHeight();
int newWidth = 640;
int newHeight = 480;
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
// create the new Bitmap object
Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 50, 50, width,
height, matrix, true);
BitmapDrawable bmd = new BitmapDrawable(resizedBitmap);
ImageView imageView = new ImageView(this);
imageView.setImageDrawable(bmd);
imageView.setScaleType(ScaleType.CENTER);
linearLayout.addView(imageView, new LinearLayout.LayoutParams(
LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
setContentView(linearLayout);
}
}
This works only if in createBitmap, the X and Y coordinates of the first pixels in the source are 0. meaning, I'm not able to take a subset of the image. Only able to scale the whole image. But createBitmap is meant to subset an image.
In the log, when the parameters are not 0, I get the following exception: java.lang.IllegalArgumentException: x + width must be <= bitmap.width()
Please help
First you have to create a new bitmap with the part you want to scale using
createBitmap() //pass the source bitmap, req height and width
Now from the result bitmap, you have to create your scaled bitmap using
createScaledbitmap() //pass the result bitmap , req width, height
For exapmle:
Bitmap originalBitmap = BitmapFactory.decodeResource(res, id);
Bitmap partImage = originalBitmap.createBitmap(width, height, config);
Bitmap scaledImage = partImage.createScaledBitmap(partImage, dstWidth, dstHeight, filter);
So I had to fix a couple of Typos, but this example did a good job for me.http://www.anddev.org/resize_and_rotate_image_-_example-t621.html
typos:
int width = bitmapOrg.width();
int height = bitmapOrg.height();
become:
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();
otherwise, worked when I tried it agains SDK 7

Categories

Resources