Develop Reference

Imageview on a random position [duplicate]

This question already has answers here:
How can I dynamically set the position of view in Android?
(13 answers)
Closed 6 years ago.
I want myImageView to locate itself somewhere on a random position inside the screen, without pushing textviews away. I found this code in another thread, but I can't get it to work.
myImageView = (ImageView) findViewById(R.id.myImageView);
LinearLayout game = (LinearLayout)findViewById(R.id.game);
int width = game.getWidth();
int height = game.getHeight();
random = new Random();
int x = width;
int y = height;
int imageX = random.nextInt(x-50)+50;
int imageY = random.nextInt(y-100)+100;
myImageView.setX(imageX);
myImageView.setY(imageY);

You can give margin programmatically between certain range, may be you can use device width or height for range. Check this links for setting margin dynamically on run time and get screen dimension.

I Think first get programmatically device size then set image view width & height
WindowManager wm = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth(); // deprecated
int height = display.getHeight(); // deprecated
hear you get width & height now set image view size
android.view.ViewGroup.LayoutParams layoutParams =myImageView.getLayoutParams();
layoutParams.width = 30;
layoutParams.height = 30;
myImageView.setLayoutParams(layoutParams);
and if you still have a problem to change it's size try to put it inside of a LinearLayout and manipulate the imageView size using the layout params:
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(30, 30);
myImageView.setLayoutParams(layoutParams);

how to draw a square in the centre of the screen in android

I am tring to draw a square in the center of the screen. I want there to be a slight margin to the left and right of the square so that is is away from the edge, the way I am trying to create it is below. The problem is that it will not display properly on all devices and that when the screen is tilted some of the square is cut off. I think this is because I use rectSide = 1000. does anybody know a better way to do this that will work on any screen size?
int rectside =1000;
canvas.drawRect(width/2 - rectSide/2,
height/2 - rectSide/2,
width/2 + rectSide/2,
height/2 + rectSide/2, paint);

You need to get height and width of device programmatically like this
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
int height = displaymetrics.heightPixels;
int width = displaymetrics.widthPixels;
Update:As pointed out by #Der Golem take the smaller between width and height so that all sides should be equal

Get the device's dimension:
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
int height = displaymetrics.heightPixels;
int width = displaymetrics.widthPixels;
Next, get the smallest dimension:
int diameter = width;
if (height < width){
diameter = height;
}
Now get an offset, I suggest using some kind of percentage of the device, e.g.
int offset = (int) (0.05*diameter);
diameter -= offset;
Finally draw it:
canvas.drawRect(width/2 - diameter/2 ,
height/2 - diameter/2,
width/2 + diameter/2,
height/2 + diameter/2, paint);

You are right, using an absolute number of pixel is not the good way.
You should adapt your rectSide using display height & width. How to get screen size attributes has already been discussed here.
I also strongly recommend you to read this, to get a better understanding of how to manage multiple screen sizes.

how to get the screen size in android?

I'm writing an app in Java and I want to place a button randomly in the screen.
I used the Display.getSize(), but it gives me the whole size of the screen including the bottom bar of the return, home and recent activities buttons. So my button which is randomly located in the screen, often is hidden under this bar. How can I take into cosideration this bar in my calculation?
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_hiding_buttons);
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
SCREEN_WIDTH = size.x;
SCREEN_HEIGHT = size.y;
}
public void button_hideButtonClick(View view) {
// init button location to beginning position
view.offsetLeftAndRight(-horizonOffset);
view.offsetTopAndBottom(-verticalOffset);
Random r = new Random();
// generate random pos relative to the screen
horizonOffset = r.nextInt(SCREEN_WIDTH-view.getWidth());
verticalOffset = r.nextInt(SCREEN_HEIGHT-view.getHeight());
// relocate the button randomly
view.offsetLeftAndRight(horizonOffset);
view.offsetTopAndBottom(verticalOffset);
}

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int width=dm.widthPixels;
int height=dm.heightPixels;
int dens=dm.densityDpi;
double wi=(double)width/(double)dens;
double hi=(double)height/(double)dens;
double x = Math.pow(wi,2);
double y = Math.pow(hi,2);
double screenInches = Math.sqrt(x+y);
as explained here
Try this..and let me know if it doesnt work..Will tell you some other options too...

scaling and rotating imageview

I'm preparing somecompass activity.
I have my rose of winds .png and I want to scale it on activity start and rotate after orientation changed.
The problem is that when i scale my image (onCreate only), after first (and only first) use of rotate method my view is resized one more time, and I have no idea why.
Let me post you my rotate and scale methods. rose is my ImageView instance (ImageView rose)
Please take a look and post any advices. Should I try different way to scale my ImageView ?
Thx for any help !
Rotate (looks like working fine)
public void rotateRose(float angle){
angle = 360 - angle;
Matrix matrix=new Matrix();
rose.setScaleType(ScaleType.MATRIX);
pivX = rose.getDrawable().getBounds().width()/2;
pivY = rose.getDrawable().getBounds().height()/2;
matrix.preRotate((float) angle, pivX, pivY);
rose.setImageMatrix(matrix);
}
Scale (found source link)
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
RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) view.getLayoutParams();
params.width = width;
params.height = height;
view.setLayoutParams(params);
//pivX = width/2;
// pivY = height/2;
}

Ok i've got it !
replace
view.setImageDrawable(result);
in Scale method with
view.setImageBitmap(scaledBitmap);
If you are looking for scaling and rotating methods for image view: These above works fine (with this little change )

Android, set WebView dimensions with px in Java

Currently I am using the following to set height and width:
//landsapeWebView is a WebView, and deviceHeight and deviceHeight are ints
landsapeWebView.setLayoutParams(new RelativeLayout.LayoutParams(deviceHeight, deviceWidth));
This seems to work fine on some devices but not others. The only conclusion I've come to is that this is setting the height and width like this:
<WebView android:layout_width="(deviceWidth)dp"
android:layout_height="(deviceHeight)dp" />
when what I want is this:
<WebView android:layout_width="(deviceWidth)px"
android:layout_height="(deviceHeight)px" />
How can I specify the unit of measure?
Extra disclosure for #collusionbdbh
display = getWindowManager().getDefaultDisplay();
if(getResources().getConfiguration().orientation == 1){
deviceWidth = display.getWidth();
deviceHeight = display.getHeight();
}else{
deviceWidth = display.getHeight();
deviceHeight = display.getWidth();
}

Try this:
DisplayMetrics metrics = this.getResources().getDisplayMetrics();
int width = metrics.widthPixels;
int height = metrics.heightPixels;

Are you sure it is not an orientation issue?
Regardless of the orientation of the device the width is the horizontal and the height is the vertical.
I would try this:
display = getWindowManager().getDefaultDisplay();
deviceWidth = display.getWidth();
deviceHeight = display.getHeight();
I am pretty sure width should be before height:
landsapeWebView.setLayoutParams(new RelativeLayout.LayoutParams(deviceHeight, deviceWidth));
should be:
landsapeWebView.setLayoutParams(new RelativeLayout.LayoutParams(deviceWidth, deviceHeight));