Recepty, články, nápady, programování. Dříve dum-zahrada, finance, internet a know-how.okhelp.cz Pro lepší výsledky hledání používejte i diakritiku.

How to capture screenshot of emulator window - Android sample


When Eclipse and the emulator runs.
To access the DDMS perspective, go to Window > Open Perspective > DDMS. If DDMS does not appear, go to Window > Open Perspective > Other ... and select DDMS.

Open Devices TAB. Window -> Show view -> Devices

From Devices TAB select Screen Capture
Android emlator screen capture by eclipse

397LW NO topic_id


Další témata ....(Topics)


EditText hint not show | edittext-hint-not-show

Try this solution - into xml file add row to EditText tag:



Every fragment must have an empty constructor Android Java Class | every-fragment-must-have-an-empty-constructor-android-java-class

You have to add constructor!

    public static class YourFragment extends Fragment {
    //you have to add constructor!!!!!	
    public YourFragment(){}

        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            View view = inflater.inflate(R.layout.activity_main, container, false);

            return view;



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;

	    // 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


How rebuild only one module in project Android Studio | how-rebuild-only-one-module-in-project-android-studio

If you do click on Rebuid project menu item, this operation maybe consume long time on slovly PC.
Some errors dismis when you do rebuild project, or module.
Try this:
Select module where contains red error code and press Debugg or Run button on Android Studio.
If module code contains errors, Android Studio show error report in gradle console.
If not, apk will installed on device.
This is 10 times faster than Clean - Rebuild all project.

Map TreeMap key value pair add put get pair by key Java Android example | map-treemap-key-value-pair-add-put-get-pair-by-key-java-android-example

Map TreeMap add key value pair get find pair by key Java Android example.


import java.util.Map;
import java.util.TreeMap;

public class MainClass {
	public static void main(String[] arg) {
		// english;germany dictionary
		String[] arrayOfString = { "one;eine", "two;zwei", "three;drei" };

		Map<String, String> map = new TreeMap<String, String>();
		for(String s: arrayOfString){
	    	String[] array = s.split(";");
	    	String sKey ="", sValue="";
	    	if(array.length > 1){
	    	sKey = array[0]; sValue = array[1];
	    		map.put(sKey, sValue);

       // check if key exists 	    
	   if( map.containsKey("two")){
		System.out.print("two = " + map.get("two"));
two = zwei

Editace: 2014-02-15 20:45:54
Počet článků v kategorii: 397

11 Share