CODEWITHSUNDEEP
androiddensity-independent-pixel
Khushboo
Khushboo

Reputation: 3163

How to determine the screen width in terms of dp or dip at runtime in Android?

I need to code the layout of the android widgets using dip/dp (in java files). At runtime if I code,

int pixel=this.getWindowManager().getDefaultDisplay().getWidth();

this return the screen width in pixels (px). To convert this to dp, I coded:

int dp =pixel/(int)getResources().getDisplayMetrics().density ;

This does not seem to be returning correct answer. I made the emulator of WVGA800 whose screen resolution is 480 by 800. When the run the emulator and let the code print the values of pixel and dp, it came to 320 in both. This emulator is 240 dpi whose scale factor would be 0.75.

Upvotes: 228

Views: 205755

Answers (13)

Frankenzilla
Frankenzilla

Reputation: 39

val screenSize = size.toDpSize()

Upvotes: 0

TheYogi
TheYogi

Reputation: 1026

2023 Answer simplified for Kotlin:

val widthDp = resources.displayMetrics.run { widthPixels / density }
val heightDp = resources.displayMetrics.run { heightPixels / density }

As one-liner:

val (height, width) = resources.displayMetrics.run { heightPixels/density to widthPixels/density }

For Jetpack Compose:

val (height, width) = LocalConfiguration.current.run { screenHeightDp.dp to screenWidthDp.dp }

Upvotes: 31

Dax
Dax

Reputation: 6918

As @Tomáš Hubálek mentioned;
Try something like:

DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();    
float dpHeight = displayMetrics.heightPixels / displayMetrics.density;
float dpWidth = displayMetrics.widthPixels / displayMetrics.density;

OR

Try old answer:

Display display = getWindowManager().getDefaultDisplay();
DisplayMetrics outMetrics = new DisplayMetrics ();
display.getMetrics(outMetrics);
         
float density  = getResources().getDisplayMetrics().density;
float dpHeight = outMetrics.heightPixels / density;
float dpWidth  = outMetrics.widthPixels / density;

Upvotes: 413

Simon Featherstone
Simon Featherstone

Reputation: 1796

In the new world of Compose on one line

val (height, width) = LocalConfiguration.current.run { screenHeightDp.dp to screenWidthDp.dp }

Upvotes: 3

Szabolcs Becze
Szabolcs Becze

Reputation: 537

This is a copy/pastable function to be used based on the previous responses.

  /**
     * @param context
     * @return the Screen height in DP
     */
    public static float getHeightDp(Context context) {
        DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
        float dpHeight = displayMetrics.heightPixels / displayMetrics.density;
        return dpHeight;
    }

    /**
     * @param context
     * @return the screnn width in dp
     */
    public static float getWidthDp(Context context) {
        DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
        float dpWidth = displayMetrics.widthPixels / displayMetrics.density;
        return dpWidth;
    }

Upvotes: 2

Bolling
Bolling

Reputation: 4073

Answer in kotlin:

  context?.let {
        val displayMetrics = it.resources.displayMetrics
        val dpHeight = displayMetrics.heightPixels / displayMetrics.density
        val dpWidth = displayMetrics.widthPixels / displayMetrics.density
    }

Upvotes: 5

math channel
math channel

Reputation: 9

If you just want to know about your screen width, you can just search for "smallest screen width" in your developer options. You can even edit it.

Upvotes: 0

Ali Azaz Alam
Ali Azaz Alam

Reputation: 1868

Get Screen Width and Height in terms of DP with some good decoration:

Step 1: Create interface

public interface ScreenInterface {

   float getWidth();

   float getHeight();

}

Step 2: Create implementer class

public class Screen implements ScreenInterface {
    private Activity activity;

    public Screen(Activity activity) {
        this.activity = activity;
    }

    private DisplayMetrics getScreenDimension(Activity activity) {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        activity.getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        return displayMetrics;
    }

    private float getScreenDensity(Activity activity) {
        return activity.getResources().getDisplayMetrics().density;
    }

    @Override
    public float getWidth() {
        DisplayMetrics displayMetrics = getScreenDimension(activity);
        return displayMetrics.widthPixels / getScreenDensity(activity);
    }

    @Override
    public float getHeight() {
        DisplayMetrics displayMetrics = getScreenDimension(activity);
        return displayMetrics.heightPixels / getScreenDensity(activity);
    }
}

Step 3: Get width and height in activity:

Screen screen = new Screen(this); // Setting Screen
screen.getWidth();
screen.getHeight();

Upvotes: 2

Supun Madushanka
Supun Madushanka

Reputation: 3238

DisplayMetrics displayMetrics = new DisplayMetrics();

getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);

int width_px = Resources.getSystem().getDisplayMetrics().widthPixels;

int height_px =Resources.getSystem().getDisplayMetrics().heightPixels;

int pixeldpi = Resources.getSystem().getDisplayMetrics().densityDpi;


int width_dp = (width_px/pixeldpi)*160;
int height_dp = (height_px/pixeldpi)*160;

Upvotes: 7

serjlee
serjlee

Reputation: 1389

I stumbled upon this question from Google, and later on I found an easy solution valid for API >= 13.

For future references:

Configuration configuration = yourActivity.getResources().getConfiguration();
int screenWidthDp = configuration.screenWidthDp; //The current width of the available screen space, in dp units, corresponding to screen width resource qualifier.
int smallestScreenWidthDp = configuration.smallestScreenWidthDp; //The smallest screen size an application will see in normal operation, corresponding to smallest screen width resource qualifier.

See Configuration class reference

Edit: As noted by Nick Baicoianu, this returns the usable width/height of the screen (which should be the interesting ones in most uses). If you need the actual display dimensions stick to the top answer.

Upvotes: 128

android developer
android developer

Reputation: 116322

How about using this instead ?

final DisplayMetrics displayMetrics=getResources().getDisplayMetrics();
final float screenWidthInDp=displayMetrics.widthPixels/displayMetrics.density;
final float screenHeightInDp=displayMetrics.heightPixels/displayMetrics.density;

Upvotes: 11

Dirk le Roux
Dirk le Roux

Reputation: 15

Your problem is with casting the float to an int, losing precision. You should also multiply with the factor and not divide.

Do this:

int dp = (int)(pixel*getResources().getDisplayMetrics().density);

Upvotes: -5

Mykhailo Gaidai
Mykhailo Gaidai

Reputation: 3160

You are missing default density value of 160.

    2 px = 3 dip if dpi == 80(ldpi), 320x240 screen
    1 px = 1 dip if dpi == 160(mdpi), 480x320 screen
    3 px = 2 dip if dpi == 240(hdpi), 840x480 screen

In other words, if you design you layout with width equal to 160dip in portrait mode, it will be half of the screen on all ldpi/mdpi/hdpi devices(except tablets, I think)

Upvotes: 8

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