Develop Reference

Draw on Custom Image view

I am working on Image Editor that allow the user to choose an image from the gallery and then draw objects on the image.
I created a custom ImageView and called setImageBitmap with the chosen image.
The problem is that the image is placed in the center of the screen and when I try to draw say a rectangle form (0, 0) to (100, 100), it is drawn starting from the left top corner of the screen not the image.
Also, the width and the height of the chosen bitmap are different from the width and the height of the canvas in onDraw() method in the custom ImageView.How is that ?

After choosing the image, make bitmap of selected image and try below code:
int currentBitmapWidth = bitMap.getWidth();
int currentBitmapHeight = bitMap.getHeight();
int ivWidth = imageView.getWidth();
int ivHeight = imageView.getHeight();
int newWidth = ivWidth;
newHeight = (int) Math.floor((double) currentBitmapHeight *( (double)
new_width / (double) currentBitmapWidth));
Bitmap newbitMap = Bitmap.createScaledBitmap(bitMap, newWidth,
newHeight, true);
imageView.setImageBitmap(newbitMap)
This will set the image to the size of your imageView.

Resizing an image to fit on a imageview

I am developing an application in which I need to fit an Bitmap into Imageview with specific dimensions(let's suppose 350dpx50dp - height*width).
I wanted to do something similar like this: http://gyazo.com/d739d03684e46411feb58d66acea1002
I have looked here for solutions. I found this code for scale the bitmap and fit it into imageview, but the problem is that imageview becomes greater when I add the bitmap into him:
private void scaleImage(Bitmap bitmap, ImageView view)
{
// Get current dimensions AND the desired bounding box
int width = bitmap.getWidth();
int height = bitmap.getHeight();
int bounding = dpToPx(350);
// 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;
// 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);
// Apply the scaled bitmap
view.setImageBitmap(scaledBitmap);
}
Using this code I can get this : http://gyazo.com/e9871db2130ac33668156fc0cf773594
But that's not what I wanted, I want to keep the dimensions of imageview and add the bitmap into imageview without modifying the dimensions of imageview and occupying all the imageview's surface. Like the first image.

Why don't you just add android:scaleType="fitXY" to your ImageView in xml?

How to get the height and width of an ImageView/Bitmap in Android

I want to get the height and width of an image bitmap that is either in ImageView or a background image. Please help me, any help will be appreciated.

You can get height and width of ImageView by using getWidth() and getHeight() through while this will not give you the exact width and height of the image, for getting the Image width height first you need to get the drawable as background then convert drawable to BitmapDrawable to get the image as Bitmap from that you can get the width and height like here
Bitmap b = ((BitmapDrawable)imageView.getBackground()).getBitmap();
int w = b.getWidth();
int h = b.getHeight();
or do like here
imageView.setDrawingCacheEnabled(true);
Bitmap b = imageView.getDrawingCache();
int w = b.getWidth();
int h = b.getHeight();
the above code will give you current imageview sized bitmap like screen shot of device
for only ImageView size
imageView.getWidth();
imageView.getHeight();
If you have drawable image and you want that size you can get like this way
Drawable d = getResources().getDrawable(R.drawable.yourimage);
int h = d.getIntrinsicHeight();
int w = d.getIntrinsicWidth();

For some reason accepted answer didn't work for me, instead I achieved the image dimension as per the target screen dpi like this.
Method 1
Context context = this; //If you are using a view, you'd have to use getContext();
Resources resources = this.getResources();
BitmapFactory.Options bounds = new BitmapFactory.Options();
bounds.inJustDecodeBounds = true;
BitmapFactory.decodeResource(resources, R.drawable.cake, bounds); //use your resource file name here.
Log.d("MainActivity", "Image Width: " + bounds.outWidth);
Here is the original link
http://upshots.org/android/android-get-dimensions-of-image-resource
Method 2
BitmapDrawable b = (BitmapDrawable)this.getResources().getDrawable(R.drawable.cake);
Log.d("MainActivity", "Image Width: " + b.getBitmap().getWidth());
It doesn't show the exact number of pixels in the image resource but a meaningful number perhaps someone can explain further.

Android Image Resize basic

I like to resize an bitmap,if it is big make it small and place it on an specific location in the surface view, I need to get device width and height and then bitmap size and place them in an surface view and then take another image resize it and place it in any location has i like.
How to know the location co ordinates first(to place second image - this should be device independent if larger/smaller screen layout should not change)
and how to scale an big bitmap and set as background so i can draw an image over it.
my code :
final int canvasWidth = getWidth();
final int canvasHeight = getHeight();
int imageWidth = img.getWidth();
int imageHeight = img.getHeight();
float scaleFactor = Math.min( (float)canvasWidth / imageWidth,
(float)canvasHeight / imageHeight );
Bitmap scaled = Bitmap.createScaledBitmap( img,
(int)(scaleFactor * imageWidth),
(int)(scaleFactor * imageHeight),
true );
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(scaled, 10, 10, null);
this scale the big image but it doesn't fit the whole screen "img - bitmap is like an background image "
Someone can help me to understand the resize basics (I'm new so finding hard to understand resizing) to resize image to fit screen and resize any image to smaller one and place it in any location i like .

Store your bitmap as a source for manipulation and display it using ImageView:
Bitmap realImage = BitmapFactory.decodeFile(filePathFromActivity.toString());
Bitmap newBitmap = scaleDown(realImage, MAX_IMAGE_SIZE, true);
imageView.setImageBitmap(newBitmap);
//scale down method
public static Bitmap scaleDown(Bitmap realImage, float maxImageSize,
boolean filter) {
float ratio = Math.min(
(float) maxImageSize / realImage.getWidth(),
(float) maxImageSize / realImage.getHeight());
int width = Math.round((float) ratio * realImage.getWidth());
int height = Math.round((float) ratio * realImage.getHeight());
Bitmap newBitmap = Bitmap.createScaledBitmap(realImage, width,
height, filter);
return newBitmap;
}
And set your ImageView's width and height to "fill_parent".

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"/>