long in java example
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.
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);
396LW NO topic_id
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Další témata ....(Topics)
public class Panel extends SurfaceView implements SurfaceHolder.Callback {
//............... code
//............... some code
/**
* Process the MotionEvent.
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
synchronized (getHolder()) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
performClick();
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
if(_currentGraphic==null)return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
}
return true;
}
}
/////////////////////////////
@Override
public boolean performClick() {
// Calls the super implementation, which generates an AccessibilityEvent
// and calls the onClick() listener on the view, if any
super.performClick();
// Handle the action for the custom click here
return true;
}
}
Warning: The application may be doing too much work on its main thread
Try this sorce code:
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.
Draw the trajectory of shot.
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
// CONSTRUCTOR
public SampleView(Context context) {
super(context);
setFocusable(true);
}
private static void makePath(Path p) {
p.moveTo(10, 0);
p.cubicTo(100, -50, 200, 150, 300, 0);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.CYAN);
Paint p = new Paint();
// smooths
p.setAntiAlias(true);
p.setColor(Color.RED);
p.setStyle(Paint.Style.STROKE);
p.setStrokeWidth(5);
// opacity
//p.setAlpha(0x80);
p.setColor(Color.BLACK);
Path mPath = new Path();
makePath(mPath);
canvas.drawPath(mPath, p); //(rectF, 90, 45, true, p);
}
}
}
android:gravity="left|center_vertical" or android:gravity="right|center_vertical"
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="left|center_vertical"
android:paddingLeft="20dp"
android:text="My Button"
/>
Android Emulator warning:[Accessibility] Missing contentDescription attribute on image
Workaround example code:
Workaround example code:
android:contentDescription="@string/desc"
<ImageView
android:id="@+id/imageViewOil"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/desc"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="84dp"
android:src="@drawable/tank_silver" />
Editace: 2011-09-26 20:49:35
Počet článků v kategorii: 396
Url:long-in-java-example