Save Instance State if device is rotated

Start Stop Stopwatch Timer Android example source code.

private static long mStartTime = 0L;
Calendar cal;
TextView hTextViewVypis = (TextView)findViewById(R.id.idTextVypis);

void start(){
            cal = Calendar.getInstance();
            mStartTime = cal.getTimeInMillis();
}

void stop(){
     prinOutStopWatchTime();
}


    private void prinOutStopWatchTime() {
    	final long start = mStartTime;
    	
    	cal = Calendar.getInstance();
    	long stopTime = cal.getTimeInMillis();
    	long millis = stopTime - start;
    	long milisekundy = millis % 1000;
    	int seconds = (int) (millis / 1000);
    	int minutes = seconds / 60;
    	seconds     = seconds % 60;
    	int hour = minutes / 60;
    	hour = hour % 60;
    	
    	if (seconds < 10) {
    		hTextViewVypis.setText(hour +  ":" + minutes + ":0" + seconds + ":" + milisekundy);
    	} else {
    		hTextViewVypis.setText(hour  +  ":" + minutes + ":" + seconds + ":" + milisekundy);            
    	}
    	
    }

Android Studio ADB restart mobile device from USB every time if RUN of DEBUG button pressed

Try to close the mobile application on your device completely before starting again from Android Studio.
Close every fragment.
The problem occurs when the application has multiple fragments.

Date: 13.07.2020 - 08:23

Check your xml files in Eclipse Graphical Editor and fix problems.



Check project setup, right click on project, select properties, Java build path and
select correct Android version etc.


Right click on project, Android Tools, Fix Project Properties

Menu Eclipse select Project ->Clean.

I You use offline work for better building speed of project or for other purpose
https://gradle.org/releases

Offline work:
File - Settings - Gradle
- select Use local gradle distribution
- select path Gradle home:
- check Offline work

int occupy 4 bytes (32 bits) in memory

int in Java example of using Integer and Array of Integer and Iteger to String

        // get max end min values of int in Java example 4 bytes (32 bits) PC architecture
	System.out.println(Integer.MAX_VALUE); // 2147483647
	System.out.println(Integer.MIN_VALUE); // -2147483648


// members variable
private int mProgress = 10;

//integer to string java
int myInteger = 8;
String myString = Integer.toString(myInteger);

// a final variable can only be initialized once
static final int NUM_PARTICLES = 15;

 for (int i = 0; i < NUM_PARTICLES ; i++) { 
// do something
}

// int as return value of function
public int getCount() {
return 5;
}

// int as a parametr of function
public float getFloatFromInt(int i) {
float fRet = (float) i;
 return fRet;
}

//array of int
int[] anArray;              // declares an array of integers
          anArray = new int[2];      // allocates memory for 2 integers
          anArray[0] = 100; // initialize first element
          anArray[1] = 200; // initialize second element

for (int i = 0; i < anArray.length; i++) {
// print out values from anArray
System.out.println("Index: " + i);
System.out.println("Value: " + anArray[i]); 
}