ACRA allows your Android application to send Crash Reports

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);

HTC Desire HD cena od 7 000 KCZ Kč (únor.2012)
HTC Desire HD je chytrý telefon běžící na operačním systému Android.
HTC Desire HD je (22.února2012) druhým nejpoužívanějším chytrým telefonem u programu Sky Map viz tabulka.

Smartphone má hliníkový unibody design, vybaven je Androidem 2.2 (Froyo) a HTC Sense displayem. Na zadní straně jsou dvě plastové krytky, jedna obsahuje baterii, druhá SIM kartu a paměťovou kartu microSDHC. Telefon je vybaven 4,3 palcovým WVGA LCD TFT dotykovým displayem, 8 megapixelovým fotoaparátem (lze nahrávat 720p video), podpora pro HSPA / W-CDMA a quad-band GSM / GPRS / EDGE.


Telefon je vybaven 1 GHz CPU Scorpion MSM8255 procesorem. Tato druhá generace Snapdragon procesoru má nízkou spotřebu energie.

HTC HD má 768 MB RAM a 1,5 GB interní paměti flash. K dispozici je také slot pro microSDHC / XC kartu s kapacitou až 32 GB dat.

HTC Desire HD photo pic image

Zdroj obrázku: wikipedia

Why the app selects data from basic layout folder if smallest width is higher then the number in folder name?
Example 1
layout-sw600dp values-sw600dp (smallest width sw for data usage from this folder is 600dp density independent pixel!!!!!)
Device screen resolution is 1200 x 900 px (pixel) Wow, app to be select data from sw600dp folder! Realy?
DPI of device screen - dot per inch (pixel per inch) is 480 pixel it is wery important number!

1. App selects smallest dimension of screen. In our case 900 px
   Medium screen have 160 dpi (The density-independent pixel is equivalent to one physical pixel on a 160 dpi screen, which is the baseline density assumed by the system for a "medium" density screen.).



2. App calculate ratio 480 / 160 = 3 (The conversion of dp units to screen pixels: px = dp * (dpi / 160))



3. App calculate smallest dimesnion of screen in dp 900 / 3 = 300 dip or dp (density independed pixel).



4. App selects data from basic values and layout folder because sw600dp is greater than 300dp.

In our case smallest dimension of screen must be at least 1800 real - physical pixels (1800 px / 3 ratio(dpi/160) = 600 dp (dip density independend pixels) to be used data from folders values-sw600dp and layout-sw600dp.


Example 2 see Example 1 abouve
Device: Nexus 7 (2012) selected from Android Studio tool layout editor
Resolution: 800x1280 px
DPI: tvdpi (approximately 213dpi)
Ratio: 1.33 (213 / 160)
Smallest width in px: 800
Convert px to dp: 601.5 (800 / 1.33)
Result:Smallest width is 601.5dp The App to be used data from folders values-sw600dp and layout-sw600dp.

Tutorial by pictures how evaluate a variable in Eclipse debugger window.

1.) Open Debug perspective in Eclipse and to start debugging a Activity.



2.) Open Display window from menu Window->Show view->Display



3.) Set breakpoint where you need to evaluate a variable.



4.) Debug the Activity to breakpoint.




5.) Into the Display window type code for evaluate your variable and execute code.




6.) Check if change of value a variable

      Spinner  _spin1 = (Spinner) findViewById(R.id.spinLangFirst);
      ArrayAdapter<String> adapterJazyky = new ArrayAdapter<String>(this,
              R.layout.spinner_text_layout.xml, {"one","two","etc...."});
      adapterJazyky.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
      _spin1.setAdapter(adapterJazyky);

spinner_text_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="//schemas.android.com/apk/res/android"
          android:id="@+id/spinnerText"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
         
         android:textSize="20sp"
/>