Rotate a image bitmap picture Android example

Rotate a bitmap Android source code.


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);

		}
		@Override
		protected void onDraw(Canvas canvas) {
			Paint paint = new Paint();
			
			canvas.drawColor(Color.YELLOW);
            
          // Bitmap b = Bitmap.createBitmap(200, 200, Bitmap.Config.ARGB_8888);
			
		    //  you need to insert a image flower_blue into res/drawable folder 
			Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.flower_blue);
			 Matrix mat = new Matrix();
			                mat.postRotate(90);
			                Bitmap bmpRotate = Bitmap.createBitmap(bmp, 0, 0,
			  bmp.getWidth(), bmp.getHeight(),
			  mat, true);
		   int h = bmp.getHeight();
           
           canvas.drawBitmap(bmp, 10,10, paint);
           canvas.drawBitmap(bmpRotate, 10,10 + h + 10, paint);
           
		}

	}
}

396LW NO topic_id

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217

How to save the state of Activity - Android | how-to-save-the-state-of-activity-android

onSaveInstanceState, onRestoreInstanceState , save preferences


int mCurrentPhotoIndex = 0;
   @Override
    protected void onSaveInstanceState(Bundle outState) {
        outState.putInt("photo_index", mCurrentPhotoIndex);
        super.onSaveInstanceState(outState);
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        mCurrentPhotoIndex = savedInstanceState.getInt("photo_index");
        super.onRestoreInstanceState(savedInstanceState);
    }

// or save preferences for new start of Activity in onStop
//onCreate or onResume or onStart etc.
public void loadPreferences() {
		SharedPreferences settings = getSharedPreferences(F.PREFERENCES_NAME, 0);
		mCurrentPhotoIndex = settings.getInt("mCurrentPhotoIndex",mCurrentPhotoIndex);
	// String_sOtazka = settings.getString("_sOtazka", _sOtazka);


}
// onStop
public void savePreferences() {
		SharedPreferences settings = getSharedPreferences(PREFERENCES_NAME, 0);
		SharedPreferences.Editor editor = settings.edit();
		editor.putInt("mCurrentPhotoIndex", mCurrentPhotoIndex);
                // String, boolean, float ...
		// editor.putString("mButton1", mButton1.getText().toString());

		editor.commit();

}

277

Change Screen Orientation Programmatically Android | change-screen-orientation-programmatically-android

Landscape - portrait orientation change:


boolean mbOrientationLandscape = true;
if(mbOrientationLandscape ){
	setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
	mbOrientationLandscape =false;
}else{
	setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
	mbOrientationLandscape =true;
}

395

ADB restart device every time Android Studio | adb-restart-device-every-time

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

Emulator window was out of view and was recentred - Android emulator warning | emulator-window-was-out-of-view-and-was-recentred-android-emulator-warning

Emulator window was out of view and was recentred
Emulator] WARNING: Data partition already in use. Changes will not persist!
Emulator] WARNING: SD Card image already in use: C:\Documents and Settings\user_name\.android\avd\hvga21_up1_7.avd/sdcard.img
Emulator] WARNING: Cache partition already in use. Changes will not persist!

Basic step
Try restart Eclipse if using from menu File->Restart

Other solutions

Solution 1: try restart ADB server
//android.okhelp.cz/how-quickly-restart-adb-exe-adb-server-android-emulator-example/

Solution 2:

Delete Run Configuration

//android.okhelp.cz/android-emulator-wont-run-application-started-from-eclipse/

Solution 3:
Try delete:


c:\Documents and Settings\user_name\.android\avd\my_avd.avd\cache.img
c:\Documents and Settings\user_name\.android\avd\my_avd.avd\userdata-qemu.img

Try solution 4:
Eclipse menu select Window->Preferences->Android

Windows 32

FROM: C:\Program Files\Android\android-sdk
TO: C:\PROGRA~1\Android\android-sdk

Windows 64

FROM: C:\Program Files (x86)\Android\android-sdk
TO: C:\PROGRA~2\Android\android-sdk

LayoutLib is too recent. Update your tool Eclipse Android | layoutlib-is-too-recent-update-your-tool-eclipse-android

LayoutLib is too recent. Update your tool!
Eclipse Android Graphical layout resolving problem.

Open in Eclipse menu Help ->Check for Updates

Select updates:

Press Next and update all

Restart Eclipse

android/layoutlib-is-too-recent-update-your-tool-300x221.png

Editace: 2011-11-15 07:01:41
Počet článků v kategorii: 396
Url:rotate-a-image-bitmap-android-example

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