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String Array of Array Java Example


Set, get string , array of array of strings, Java example code

	public final static String[][]_arArOfString_1 = {
		new String[] {"bla","bla","hello world!"},
		new String[] {},
		new String[] {},
		new String[] {},
		new String[] {},
		new String[] {}
String sOut = _arArOfString_1[0][2]; // hello world!

397LW NO topic_id


Další témata ....(Topics)


onSensorChanged Android example | onsensorchanged-android-example

Sensor, getSystemService(), getSensorList(), getDefaultDisplay(), WindowManager,
Surface.ROTATION_0, onAccuracyChanged() Android sample.

public class _MotionActivity extends Activity implements SensorEventListener {
    private float mSensorX;
    private float mSensorY;
    private Display mDisplay;
    private SensorManager sm;
    private PowerManager mPowerManager;
    private WindowManager mWindowManager;
    TextView textview;

    public void onCreate(Bundle savedInstanceState) {
        // Get an instance of the SensorManager
        sm = (SensorManager) getSystemService(SENSOR_SERVICE);
        	Sensor s = sm.getSensorList(Sensor.TYPE_ACCELEROMETER).get(0);
        	sm.registerListener(this,s, SensorManager.SENSOR_DELAY_NORMAL);

        // Get an instance of the PowerManager
        mPowerManager = (PowerManager) getSystemService(POWER_SERVICE);

        // Get an instance of the WindowManager
        mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
        mDisplay = mWindowManager.getDefaultDisplay();

        textview = (TextView)findViewById(R.id.textView1);
    public void onSensorChanged(SensorEvent event) {

        if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER)

        switch (mDisplay.getRotation()) {
            case Surface.ROTATION_0:
                mSensorX = event.values[0];
                mSensorY = event.values[1];
                textview.setText(String.valueOf( mSensorX));
            case Surface.ROTATION_90:
                mSensorX = -event.values[1];
                mSensorY = event.values[0];
                textview.setText(String.valueOf( mSensorX));
            case Surface.ROTATION_180:
                mSensorX = -event.values[0];
                mSensorY = -event.values[1];
                textview.setText(String.valueOf( mSensorX));
            case Surface.ROTATION_270:
                mSensorX = event.values[1];
                mSensorY = -event.values[0];
                textview.setText(String.valueOf( mSensorX));


	public void onAccuracyChanged(Sensor sensor, int accuracy) {
		// TODO Auto-generated method stub
	protected void onResume() {

        	Sensor s = sm.getSensorList(Sensor.TYPE_ACCELEROMETER).get(0);
        	sm.registerListener(this,s, SensorManager.SENSOR_DELAY_NORMAL);

	protected void onPause() {


Screen size density independent pixel resolution | screen-size-density-independent-pixel-resolution

Terms Screen size, density, density independent pixel, resolution as a picture - pictogram.

Test your knowledge
Q: How to find out the phone screen size?
A: (By length of display diagonale in inch -  Not to measure a diagonal of device!!!)

Q: What resolution has 720 x 1280 display?
A: (921600 pixels)

Q: What does it mean "240 dpi" screen density?
A: (Display have density 240 x 240  dots - "Tri-color LED etc." - per every physical (real) square inch. If you have icon 240x240 pixels, this will just occupy an area of one square inch on the display.)

Q: Phone have screen density 240 dpi. Image for 160 dpi screen density have size 128x 128 pixels. What will be the size of the image for 240 dpi screen density?
A: (Calculate the virtual pixels size.   128 * (240/160)  =  192.  You have to resize image to new size 192 x 192 physical pixels and put into folder drawable-hdpi (high) ~240dpi  for phone with screen density 240 dpi. ) or use density independend pixels 128dp x 128dp.



WebView change height Android Example | webview-change-height-android-example

The Android WebView changing the height according to text size.
If you need to change the height to a minimum try this source:

//public void loadDataWithBaseURL (String baseUrl, String data, String mimeType, String encoding, String historyUrl) 
WebView _webView; // findById(.....
String entryContent = "";
	"blabol",//  javascript i styly
	entryContent, null,
	"utf-8", null


Eclipse Log.e println needs a message | eclipse-log-e-println-needs-a-message

Log.e println needs a message error.
E/AndroidRuntime(330): FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{b.paint/b.paint.MainActivity}: java.lang.NullPointerException: println needs a message

Try this code:

		// Error
                String s = null;
		Log.e("bla", s); // !!! error Log.e println needs a message error.
                // OK
		String s = null;
		Log.e("bla", s+""); // OK 


How get Android SDK location on PC with Eclipse | how-get-android-sdk-location-on-pc-with-eclipse

How get Android SDK location - PATH on PC from Eclipse tutorial.

  1. Open dialog from menu Window -> AVD and SDK manager

  2. In dialog select Available packages

  3. On top of dialog will displayed similar path: SKD Location: C:\PROGRA~1\Android\android-sdk-windows\

Editace: 2013-12-09 11:04:09
Počet článků v kategorii: 397

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