Develop Reference

How can i set an onclick for imageview to display full image?

I have a code which dynamically adds images and imageviews to my app. I want to set an onClick for all imageviews so that when each image is clicked, the image is displayed in full like how when you click on a facebook image it opens up and you can click next and previous.I have seen alot of other questions and answers but none of them fit what i am looking for.
final int[] images = { R.drawable.abi1, R.drawable.abi2, R.drawable.abi3,
R.drawable.abi4 };
LinearLayout linearLayout1 = (LinearLayout) findViewById(R.id.bottomView);
for (int x = 0; x < images.length; x++) {
final Bitmap bitmapOrg = BitmapFactory.decodeResource(getResources(),
images[x]);
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();
int newWidth = 200;
int newHeight = 200;
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
matrix.postRotate(0);
Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0, width,
height, matrix, true);
BitmapDrawable bmd = new BitmapDrawable(getResources(),
resizedBitmap);
ImageView imageView = new ImageView(this);
imageView.setPadding(2, 0, 9, 5);
imageView.setImageDrawable(bmd);
imageView.setTag(x);
imageView.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
linearLayout1.addView(imageView);
}

From onClick() method you can start new activity
Intent intent = new Intent(YourActivity.this, YourFullScreenActivity.class);
intent.putExtra("selected_image", int imageResourceId);
startActivity(intent);
In your new activity use ViewPager to show images in fullscreen. ViewPager will let you switch to next image. There is a lot of tutorials about implementing ViewPager.
Notice that within intent I am passing "selected_image" extra. Your new activity can use it to show immediately selected image.
By the way, with your code you can have out of memory errors if you have very high resolution images. This site http://developer.android.com/training/displaying-bitmaps/load-bitmap.html explain how to load bitmaps efficiently. In case you are showing only images from your app resource folder you could skip loading bitmaps at all. Just call setImageResource(), set size with setLayoutParams() and setScaleType() if needed. Android system will scaled them for you.

ImageView cutting from sides after rotation

I have a custom ImageView. I want to rotate my imageview at some angle. Here is its onDraw() method:
canvas.save();
canvas.rotate(currentAngle,getWidth()/2,getHeight()/2);
super.onDraw(canvas);
The image is rotating but the problem is after rotation, the images is cutting from sides. How to avoid that cutting thing?
Sample Screenshot:

Try for the following code:
public class bitmaptest extends Activity {
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
LinearLayout linLayout = new LinearLayout(this);
// 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;
// createa 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
)
);
// set LinearLayout as ContentView
setContentView(linLayout);
}
}

Was once I have a similar problem. I was decided this problem that
way. I zoomed image in so that it looked like
|_ __ |
| | | |
||_||
|_ __ _|
Half width image added left and right. And half height added top and bottom. New space fill some color, or do alapha canal equals+ 0. When you rotate the image, you needed cut the excess. I did that not on Android, but i hope this can help you.

Setting wallpaper

Im trying to set my bitmap image as a wallpaper!
Im currently using this code to get it done.
WallpaperManager wpm = WallpaperManager.getInstance(this);
float minH = wpm.getDesiredMinimumHeight();
float minW = wpm.getDesiredMinimumWidth();
Log.d("seb", minH + " = Min Height");
Log.d("seb", minW + " = Min Width");
targetBitmap = Bitmap.createScaledBitmap(targetBitmap,(int)minW, (int)minH, false);
wpm.setBitmap(targetBitmap);
It works! The phone automatically resizes the bitmap to fit the screen, but no mather how small my bitmap is, it's always cropped horizontally and scaled up.
Does anyone know how to fix this?
(One fix would be to put a black border around and have them cropped instead of the actual picture, though Im guessing there is a better alternative )
EDIT
this is original picture in code.
The following picture is what I mean with cropped when set to wallpaper:
And this will be in the same way even if i resize the image since the system automatically enlarges the picture to fit the whole screen

Ok, so after our discussion in "comments", here is a solution which can work.
Try that:
public Bitmap getResizedBitmap(Bitmap bm, int newHeight, int newWidth) {
int width = bm.getWidth();
int height = bm.getHeight();
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);
// recreate the new Bitmap
Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false);
return resizedBitmap;
}
Try it and if you have the same (or another) problem, let me know and we will try to fix it.

rotate bitmap and maintain size

I am creating a tile board game.
I want to rotate a bitmap tile piece by a few pre-determined degrees.
When I rotate my bitmap, the size changes.
For example, if I want a 75x75 triangle tile piece, on rotation I get a 68x68 back from this code. How can I keep things the same size so everything remains the size for the board?
Here's what I'm using to rotate:
public class RotatebitmapActivity extends Activity {
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
LinearLayout linLayout = new LinearLayout(this);
// load the origial BitMap (500 x 500 px)
Bitmap bitmapOrg = BitmapFactory.decodeResource(getResources(),
R.drawable.t123);
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();
int newWidth = 75;
int newHeight = 75;
// calculate the scale - in this case = 0.4f
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// createa matrix for the manipulation
Matrix matrix = new Matrix();
// resize the bit map
matrix.postScale(scaleWidth, scaleHeight);
// rotate the Bitmap
matrix.postRotate(120);
// 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
)
);
// set LinearLayout as ContentView
setContentView(linLayout);
}

What is happening in your code, is that the bitmap that is created is the correct size. However, all Bitmaps are automatically scaled to fit the density of the screen that is currently in use.
There are two ways (that I know of) to get the result you desire.
You can set the density of a bitmap after creating it and before wrapping it in a drawable. To do this, add code similar to:
resizedBitmap.setDensity(DisplayMetric.DENSITY_HIGH);
This code sets the density that the bitmap is designed for, and can prevent Android from auto-scaling the image.
The second solution is more of a methodology than a specific solution to this particular problem. I won't go into detail, for that see Supporting Multiple Screens | Android Developers
Hopefully someone will happen along that can answer your question better than I can.

Displaying images and managing memory in android

I wrote a program that at any time displays 8 user selected images on the screen. Each image is taken from its original form and scaled down to a uniform size. In order to do this I am using the code below:
Bitmap bitmapOrg = BitmapFactory.decodeFile(File Location Here);
int width = bitmapOrg.getWidth();
int height = bitmapOrg.getHeight();
int newWidth = 100;
int newHeight = 100;
// calculate the scale - in this case = 0.4f
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// createa matrix for the manipulation
Matrix matrix = new Matrix();
// resize the bit map
matrix.postScale(scaleWidth, scaleHeight);
// 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);
ImageView iv = (ImageView) findViewById(R.id.imageView1);
// set the Drawable on the ImageView
iv.setImageDrawable(bmd);
// center the Image
iv.setScaleType(ScaleType.CENTER);
Even though my code works its not perfect. It seems like I'm using up a lot of memory especially calling this code possibly 8 times at once. Where in the code would I "recycle" the memory and how could I make this code possibly run better?
EDIT:
So I implemented the code in my project and it was working perfect and then I tried to add it to other sections and it just stopped working all together. My code looks like this: any idea what am I doing wrong?
BitmapFactory.Options options = new BitmapFactory.Options();
options.outWidth = 50;
options.outHeight = 50; Bitmap bitmap = BitmapFactory.decodeFile(path, options);
ImageView iv = (ImageView) findViewById(R.id.imageView7);
iv.setImageBitmap(bitmap);

You can use BitmapFactory.Options to scale the image as you decode it rather than reading in a full image and then scaling it.
BitmapFactory.Options options = new BitmapFactory.Options();
// You can play with this setting depending on how large your images are
// For example, to scale ~400x400 images to ~100x100, you can use 4.
options.inSampleSize = 4;
Bitmap bitmap = BitmapFactory.decodeFile(path, options);
Edit - George is correct. You should use inSampleSize to create a smaller image of the general size you need and then have it resized to the exact size you want using your ImageView. I've corrected my answer above to reflect this.
In any case, you should be much better off memory-wise if you are scaling the bitmaps during decode.

#matthew-willis I do not think you can use outWidth and outHeight to scale a bitmap. I believe they are output parameters only: they report the size of the bitmap created after the fact--setting them prior to decoding has no effect. You should use inSampleSize if you want to scale as you decode. George