How to scale imageview image to specific size? - android

I created an imageview image, but I want to scale it to be no greater than a fifth of the width and a sixth of the height of the android device's screen size.
Here I get the width and height of the screen:
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int width = metrics.widthPixels;
int height = metrics.heightPixels;
here I create my imageview:
ImageView imageView = new ImageView(this);
imageView.setImageResource(icons[0]);
and here I try to scale my imageview:
imageView.getDrawable().setBounds(0, 0, width/5, height/6);
This last part is the stickler. After typing this in I get no errors and my program runs normally - but the image is not scaled. Basically that last line of code seems to have no effect and I have no idea why, any pointers?
Rest of my code:
imageView.setAdjustViewBounds(true);
int mh = imageView.getDrawable().getIntrinsicHeight();
int mw = imageView.getDrawable().getIntrinsicWidth();
imageView.setX(width/2 - Math.round(width/5));
imageView.setY(height/2 - Math.round(height/6) - mActionBarSize);
relativeLayout.addView(imageView);
setContentView(relativeLayout);

do this :
imageView.getLayoutParams().height = (int) Math.round(height/6);
imageView.getLayoutParams().width = (int) Math.round(width/5);
imageView.requestLayout(); // If you're setting the height/width after the layout has already been 'laid out'
see this link to learn more about requestLayout():
Call this when something has changed which has invalidated the layout of this view. This will schedule a layout pass of the view tree.
But ususally the view is calling it automatically, you don't have to care about that... (So for me I use it to force the view to do what I want to do)

Use this
ImageView imgView = (ImageView) findViewById(R.id.pageImage);
imgView.getLayoutParams().height = 100;
imgView.getLayoutParams().width = 100;

Related

How to scale a image (dynamic imageviews)

This is my code to create dynamic imageviews. Image get aligned really well but I need to make it small. How can I scale the image?
This is a in a LinearLayout:
for(int i=0;i<value1;i++) {
ImageView image = new ImageView(Home.this);
image.setImageResource(R.drawable.bulb);
image.setScaleX(1);
image.setScaleY(1);
image.setScaleType(ImageView.ScaleType.MATRIX);
rR.addView(image);
}
This is my code to create dynamic imageviews . Image get aligned really well but i need to make it small. How can i scale the image?
Please set the proper height and width of your dynamic image view.
Please try below code it's helpful to you.
for (int i = 0; i < 3; i++)
{
ImageView image = new ImageView(ImageScalling.this);
image.setImageResource(R.drawable.ic_launcher);
image.setLayoutParams(new LinearLayout.LayoutParams(200, 200));
image.setScaleType(ImageView.ScaleType.FIT_XY);
rR.addView(image);
}
I have set width and height is 200. If you want the show a small image then set less than 200.
For scaling imageview try this link
https://argillander.wordpress.com/2011/11/24/scale-image-into-imageview-then-resize-imageview-to-match-the-image/
You can set the size of Imageview according to screen size like 20% of height .
Display display = getWindowManager().getDefaultDisplay();
int height = display.getHeight();
int width = display.getWidth();
float mReqPercentages =20.0;
float mCalculatedWidth = (mReqPercentages / 100) * height;
image.getLayoutParams().height = (int) (mCalculatedWidth * 1.5);
image.getLayoutParams().width = (int) mCalculatedWidth;

Android Layout- adjusting bitmaps to fill screen size- weird phenomenon

I'm trying to adjust 3 bitmaps to fill screen height (and width) with relative layout.
I've solved most of the problem but I still can't figure out why it works! I won't be able to relax until I do... so please try and help me understand the following:
DisplayMetrics displayMetrics = new DisplayMetrics();
WindowManager wm = (WindowManager) getApplicationContext().getSystemService(Context.WINDOW_SERVICE); // the results will be higher than using the activity context object or the getWindowManager() shortcut
wm.getDefaultDisplay().getMetrics(displayMetrics);
int screenWidth = displayMetrics.widthPixels;
int screenHeight = displayMetrics.heightPixels;
ImageView imgTop= (ImageView) findViewById(R.id.boardTop);
ImageView imgMid= (ImageView) findViewById(R.id.boardMid);
ImageView imgBot= (ImageView) findViewById(R.id.boardBot);
top = BitmapFactory.decodeResource(getResources(), R.drawable.board_top);
mid = BitmapFactory.decodeResource(getResources(), R.drawable.board_mid);
bot = BitmapFactory.decodeResource(getResources(), R.drawable.board_bot);
top = Bitmap.createScaledBitmap(top, top.getWidth(), (int) (screenHeight*0.2), false);
mid = Bitmap.createScaledBitmap(mid, mid.getWidth(), (int) (screenHeight*0.6), false);
bot = Bitmap.createScaledBitmap(bot, screenWidth, (int) (screenHeight*0.2), false);
imgTop.setImageBitmap(top);
imgMid.setImageBitmap(mid);
imgBot.setImageBitmap(bot);
First I've used the code above and got that (I've hidden the pictures):
Then I've changed the 3 "createScaledBitmap" lines to the following:
top = Bitmap.createScaledBitmap(top, screenWidth, (int) (screenHeight*0.2), false);
mid = Bitmap.createScaledBitmap(mid, screenWidth, (int) (screenHeight*0.6), false);
bot = Bitmap.createScaledBitmap(bot, screenWidth, (int) (screenHeight*0.2), false);
(I've changed them so that all of them recieved the screenWidth value).
After the change above, I've recieved this (I've given each bitmap a different color so it's easier to see):
So it somehow fixed the bitmaps to fill all the screen height, though it still didn't grant the bottom bitmap the full screen width (as it should because I've given it the same values as the 2 other bitmaps above- also in the XML file).
So how come this happened? I believe I don't know how those bitmap classes really work. Please help me understand thoroughly what happened here.
Thanks a lot!

Android: How to find scale ratio of background image

OK, so I have an image that I am using in an ImageView to fill the screen. I am keeping the aspect ratio by using scaletype="centerCrop", as seen here:
<ImageView
android:id="#+id/imageView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:scaleType="centerCrop"
android:src="#drawable/full_bg" />
In code, how do I go about finding the scale ratio, or scale factor, that resulted from the original image to the scaled image? I need to know so I can apply this same ratio to a button positioned strategically on top of the background. This is what I have tried to get the scale ratio:
ImageView view = (ImageView) findViewById(R.id.imageView1);
Log.i("Test", "x scale = " + Float.toString(view.getScaleX()));
This returns a 1.0 (unscaled) which isn't what I'm looking for. I also tried getting the dimensions of the scaled Bitmap instead of the ImageView, which also gives me the original image size (540px):
ImageView view = (ImageView) findViewById(R.id.imageView1);
Drawable drawing = view.getDrawable();
Bitmap bitmap = ((BitmapDrawable)drawing).getBitmap();
Log.i("Test", "width = " + Integer.toString(bitmap.getWidth()));
Am I approaching this all wrong? I can't find anything to help me figure this out. Any help would be much appreciated!
Try this: I got this to change the image size depending on the size of the screen, but this could be easily changed by changing
int width = metrics.widthPixels;
to be
int width = bitmap.getWidth();
or whatever you want it to be scaled to. Note width is the size you're going to.
public static void changeImageSize(ImageView object, Context context){
DisplayMetrics metrics = new DisplayMetrics();
((WindowManager)context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getMetrics(metrics);
int width = metrics.widthPixels;
int height = metrics.heightPixels;
BitmapDrawable bmap = (BitmapDrawable) object.getDrawable();
RelativeLayout.LayoutParams layout = (LayoutParams) object.getLayoutParams();
float bmapWidth = bmap.getBitmap().getWidth();
float bmapHeight = bmap.getBitmap().getHeight();
int newBmapWidth = (int) (bmapWidth*width/480);
int newBmapHeight = (int) (bmapHeight*height/800);
layout.width = newBmapWidth;
layout.height = newBmapHeight;
object.setLayoutParams(layout);
}

Android Programming: How to maintain image size on different displays?

e.g. I want a given Bitmap (100x200px) to always have the following size:
height = 1/10 of the screens height
length = 1/20 of the screens length,
no matter how large the screen is and what resolution it has. How can I do this without creating versions of my bitmap for each of the drawable folders (I've seen examples where all the pictures where only stored in the "drawable" folder, so there must be away without creating 4 instances of each picture used)?
Thanks for the help!
Load your bitmap into an ImageView and set the ScaleType of the ImageView to 'FIT_XY' and it will scale your image to whatever size your ImageView is. You can set the ImageView size to be relative to your screen size by getting the screen dimensions from the WindowManager
For example:-
int screenWidth = getWindowManager().getDefaultDisplay().getWidth();
int screenHeight = getWindowManager().getDefaultDisplay().getHeight();
float newWidth = 0.05f * screenWidth;
float newHeight = 0.10f * screenHeight;
imageview.setScaleType( ImageView.ScaleType.FIT_XY );
imageview.setLayoutParams(new LinearLayout.LayoutParams( (int)newWidth, (int)newHeight ));
final int width = getWindowManager().getDefaultDisplay().getWidth();
final int height = getWindowManager().getDefaultDisplay().getHeight();
then use bitmapfactory to scale the image

Android Changing image size depending on Screen Size?

So I need to change the size of an image depending on the area of the screen. The image will have to be half of the screen height, because otherwise it overlaps some text.
So Height= 1/2 Screen Height.
Width = Height*Aspect Ratio (Just trying to keep the aspect ratio the same)
I found something that was:
Display myDisplay = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int width =myDisplay.getWidth();
int height=myDisplay.getHeight();
But how would I change image height in java? or even XML if possible? I can't seem to find a working answer.
You can do this with LayoutParams in code. Unfortunately there's no way to specify percentages through XML (not directly, you can mess around with weights, but that's not always going to help, and it won't keep your aspect ratio), but this should work for you:
//assuming your layout is in a LinearLayout as its root
LinearLayout layout = (LinearLayout)findViewById(R.id.rootlayout);
ImageView image = new ImageView(this);
image.setImageResource(R.drawable.image);
int newHeight = getWindowManager().getDefaultDisplay().getHeight() / 2;
int orgWidth = image.getDrawable().getIntrinsicWidth();
int orgHeight = image.getDrawable().getIntrinsicHeight();
//double check my math, this should be right, though
int newWidth = Math.floor((orgWidth * newHeight) / orgHeight);
//Use RelativeLayout.LayoutParams if your parent is a RelativeLayout
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
newWidth, newHeight);
image.setLayoutParams(params);
image.setScaleType(ImageView.ScaleType.CENTER_CROP);
layout.addView(image);
Might be overcomplicated, maybe there's an easier way? This is what I'd first try, though.

Categories

Resources