Display screen size resolution density dimension Android

AD MOB

Get display, screen resolution - dimension Android phone development example source code.


 Display display = getWindowManager().getDefaultDisplay();
int nWidth = display.getWidth();
int nHeight = display.getHeight();

          DisplayMetrics metrics = new DisplayMetrics();
            getWindowManager().getDefaultDisplay().getMetrics(metrics);
            //get density per inch for example: 120 , 160 , 240
            mXDpi = metrics.xdpi; // 160 The exact physical pixels per inch of the screen in the X dimension. 
            mYDpi = metrics.ydpi;

// density
int nDensity = metrics.densityDpi; // 160 screen density expressed as dots-per-inch

          float  mMetersToPixelsX = mXDpi / 0.0254f; // 1 inch == 0.0254 metre
          float  mMetersToPixelsY = mYDpi / 0.0254f;
          
// Resolution
// The total number of physical pixels on a screen.
int wPix = metrics.widthPixels; // 320 The absolute width of the display in pixels.
int hPix = metrics.heightPixels; // 480 The absolute height of the display in pixels.
int nWidthDisplay = (wPix < hPix)? wPix : hPix;

float nWidthScreenInInch = wPix / mXDpi; //320 / 160 == 2.0 in inch.
float nHeightScreenInInch = hPix / mYDpi; //480 / 160 == 3.0 in inch.

// for example:
// density 120 per inch
//width 320 pix / 120 dpi == width 2.66 inch
//height 480 pix / 120 dpi == height 4.0 inch 

// density 240 per inch
//width 320 pix / 240 dpi == width 1.33 inch
//height 480 pix / 240 dpi == height 2.0 inch

Example:
HTC Desire HD
11 (4.3) Diagonal cm (in)
480×800 Resolution
85 (217) ppcm (PPI - Pixels per inch)

480 / 217 = 2.21 inch
800 / 217 = 3.69 inch
Math.sqrt( 2.21*2.21 + 3.69 * 3.69) = 4.3 inch - diagonal

//en.wikipedia.org/wiki/Pixels_per_inch
//en.wikipedia.org/wiki/Dots_per_inch

Typical screen widths:

320dp: a typical phone screen (240x320 ldpi, 320x480 mdpi, 480x800 hdpi, etc).
480dp: a tweener tablet like the Streak (480x800 mdpi).
600dp: a 7” tablet (600x1024 mdpi).
720dp: a 10” tablet (720x1280 mdpi, 800x1280 mdpi, etc).

Emulator skins in the Android SDK
//developer.android.com/guide/practices/screens_support.html

	Low density (120), ldpi	Medium density (160), mdpi	High density (240), hdpi	Extra high density (320), xhdpi
Small screen	QVGA (240x320)		480x640
Normal screen	WQVGA400 (240x400) WQVGA432 (240x432)	HVGA (320x480)	WVGA800 (480x800) WVGA854 (480x854) 600x1024	640x960
Large screen	WVGA800 (480x800) WVGA854 (480x854)	*WVGA800 (480x800) WVGA854* (480x854)** 600x1024
Extra Large screen	1024x600	WXGA (1280x800)^† 1024x768 1280x768	1536x1152 1920x1152 1920x1200	2048x1536 2560x1536 2560x1600
* To emulate this configuration, specify a custom density of 160 when creating an AVD that uses a WVGA800 or WVGA854 skin. ** To emulate this configuration, specify a custom density of 120 when creating an AVD that uses a WVGA800 or WVGA854 skin. † This skin is available with the Android 3.0 platform

397LW NO topic_id

Další témata ....(Topics)

float in Java example code | float-in-java-example-code

Android development
Java float is 32 bit single precision type and used when fractional precision calculation is required.

Java float je 32 bitů veliké číslo sloužící především pro přesný výsledek za desetinnou tečkou například při dělení čísel. Pro větší přesnost použíijte 64 bitový typ Double.


		// declaration and assignment of value  type float
		float x = 18.41785f;
		//print formated  value
		System.out.printf("The value of x is %.3f%n", x); // 18.418
                
                // declaring more variables in single statement
                float f1 = 12.4F, f2 = 564.5F, f3 = 14.589F;

		// float range of value
		System.out.println(Float.MIN_VALUE); // 4E-45
		System.out.println(Float.MAX_VALUE); // 4028235E38

		// is NaN  Not-a-Number
		float f = (float) Math.sqrt(-15);
		boolean bNaN = Float.isNaN(f);
		System.out.print(bNaN); // true
		
                // check if a string is a valid number in Java example
                // convert string to float Java example
		String sF = "12.8";
		float fParse = Float.parseFloat(sF);

	       // convert strings to numbers
	      String sFl = "15.48";
	      float fFromString = (Float.valueOf(sFl)).floatValue();

// float to string in Java example code
Float fObj = new Float(68.5);
String str = fObj.toString();
// else 
Float fS = 11.6f;
String sFloat = fS.toString();

              // compare two float variables
	      Float fComp1 = 4.3f;
	      if(fComp1.equals(4.3f))
	  		System.out.print("true");

	    // compares the two specified float values in Java example
	    int i =	Float.compare(11.5f, 11.7f); // -1 first < second
	    // 0 first == second
	    // 1 first > second
	    System.out.print(i);

How set text to TextView as HTM HTML format Android example | how-set-text-to-textview-as-htm-html-format-android-example

Html.fromHtml(), setText(), textView.setText(Html.fromHtml(String htmlFormat)), Android example.


TextView mIdTextOk = (TextView)findViewById(R.id.idTextOk);
int _nOk = 57;
// number 57 will bold style
mIdTextOk.setText(Html.fromHtml( "OK: "+"<b>"+_nOk+"</b>"));

356

No USB devices or running detected | no-usb-devices-or-running-detected

Check

is sett debug mode on device?

enabled debugging over USB?

is device right connected?

have you downloaded and instaled drivers for your device on PC?

For Windows //developer.android.com/sdk/win-usb.html

try disconnect and connect USB cable

try do restart Android Studio

Is NaN isNaN isInfinite number value Java Android example | is-nan-isnan-java-example

float, double is NaN isNaN() isInfinite() Java Android example.


float f = 0.f;
boolean bIsNaN = Float.isNaN(f);
boolean bIsInfinite = Float.isInfinite(f);

 double d = Math.sqrt(-10);
 boolean b = Double.isNaN(d);

246

Set Custom Font to View Android Example | set-custom-font-to-view-android-example

You have to put your font fonts/samplefont.ttf into assets/fonts folder in your project!


// set own custom font from assets
TextView txt = (TextView) findViewById(R.id.custom_font);
Typeface mFace = Typeface.createFromAsset(getContext().getAssets(),
                                             "fonts/samplefont.ttf");
    txt.setTypeface(mFace);

Editace: 2012-07-04 15:25:45
Počet článků v kategorii: 397
Url:display-screen-dimension

AD