build.gradle in module have higher priority then AndrodiManifest.xml
Try this.
AndroidManifest.xml have code:

    <uses-sdk
        android:minSdkVersion="9"
        android:targetSdkVersion="23" />

build.gradle have code:

   defaultConfig {
        applicationId "cz.okhelp.words"
        minSdkVersion 9
        targetSdkVersion 19
        versionCode 107
        versionName "1.0.7"
    }

Warning in AndroidManifest.xml:
This targetSdkVersion value (23) is not used; it is always overridden by the value specified in the Gradle build script (19) less... (Ctrl+F1)
The value of (for example) minSdkVersion is only used if it is not specified in the build.gradle build scripts. When specified in the Gradle build scripts, the manifest value is ignored and can be misleading, so should be removed to avoid ambiguity.

Warning: The application may be doing too much work on its main thread
Try this sorce code:

import android.os.StrictMode;

public class MyActivity extends Activity {
	static{
		StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
		StrictMode.setThreadPolicy(policy);
	}
	@Override
    public void onCreate(Bundle savedInstanceState) {
//.................. etc.

List LinkedList Collections add sort find search Item, get searched item to string in Java example.

MainClass.java

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = {"nothing", "Hello", "people"
				, "bye-bye", "hello", "world!", "End" };
		   
                   List<String> arrayList = new LinkedList<String>();
                  
                   for(String s: arrayOfString)
		     arrayList.add(s);

		    Collections.sort(arrayList);
		    // foreach
		    for (String str: arrayList)
		      System.out.println(str);
		    
		    Object objMin = Collections.min(arrayList);
		    System.out.println("Min is: " + objMin);
		    
		    Object objMax = Collections.max(arrayList);
		    System.out.println("Max is: " + objMax);
		    
		    int index = Collections.binarySearch(arrayList, "people");
		    System.out.println("Index of people is: " + index);
		    // print word on index 5
		    System.out.println("Index 5 is: " + arrayList.get(5));
                    String sItem = arrayList.get(5); // get item from index 5 to string
		    
		  }
}
/*
End
Hello
bye-bye
hello
nothing
people
world!
Min is: End
Max is: world!
Index of people is: 5
Index 5 is: people
*/

Android development

long is 64 bit signed type and used when int is not large enough to hold the value.

long je celé číslo 64 bitů -9223372036854775808 +9223372036854775807 a používá se tam, kde typ int není schopen pojmout takovou hodnotu čísla.

		// declaration and assignment of value type long
		long n = 22337203685477580L;
		// print formated value
		System.out.printf("The value of x is %d%n", n); // 22337203685477580
		System.out.format("%+,8d%n%n", n); // +22 337 203 685 477 580

		// declaring more variables in single statement
		long lo1 = 12L, lo2 = 56, lo3 = 1455555555589L;

		// long range of value
		System.out.println(Long.MAX_VALUE); // 9223372036854775807
		System.out.println(Long.MIN_VALUE); // -9223372036854775808

		// check if a string is a valid number in Java example
		// convert string to long Java example
		String sLong = "1288888888888888";
		long longParse = Long.parseLong(sLong);

		// convert strings to numbers
		long longFromString = (Long.valueOf(sLong)).longValue();

		// long to string in Java example code
		Long longObj = new Long(229999999999L);
		String str = longObj.toString();
		// else
		Long longS = 888888888888L;
		String strLong = longS.toString();

		// compare two long variables
		Long longComp1 = 5555L;
		if (longComp1.equals(55555555L))
			System.out.print("true");

		// compares the two specified long values in Java example

		int i = longS.compareTo(444444L); // -1 first < second
		// 0 first == second
		// 1 first > second
		System.out.print(i);

Eclipse Navigation Shortcuts.

Keyboard_shortcuts_(3.0).pdf
Ctrl+1 Quick fix problem

Ctrl+O Quick Outline

Ctrl+Shift+G Find references in workspace
Ctrl+Shift+U Find all references in file

Ctrl+Shift+T Find Java Typ

[caption id="attachment_1214" align="alignleft" width="150" caption="eclipse-ctrl-shift-t"][/caption]

Ctrl+Shift+R Find Resource

Ctrl+E Open Editor Drop-Down
Ctrl+Space Content Assist

Ctrl+Shift+Space Context Information

F3 Open Declaration of variable
F4 Open Type Hierarchy
Ctrl+H Open Search Dialog
Alt+Shift+R Rename - Refactoring
Alt+Shift+M Extract Method
Alt+Shift+L Extract Local Variable

Alt Shift Up Expand selection to enclosing element
Alt Shift Right Expand selection to next element
Alt Shift Left Expand selection to previous element
Alt Shift Down Restore previous selection

Breakpoints Shift+Alt+Q B
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