Fixes and tweaks

AndroidManifest.xml

@@ -4,15 +4,27 @@
     android:versionCode="2"
     android:versionName="1.1" >
 
-    <uses-sdk android:minSdkVersion="7" />
-
+    <uses-sdk 
+        android:minSdkVersion="7" 
+        android:targetSdkVersion="17" 
+        />
+    <supports-screens 
+        android:resizeable="true"
+        android:smallScreens="true"
+        android:normalScreens="true"
+        android:largeScreens="true"
+        android:xlargeScreens="true"
+        android:anyDensity="true"/>  
     <application
         android:icon="@drawable/ic_launcher"
-        android:label="@string/app_name" >
+        android:label="@string/app_name"
+        android:allowBackup="true"
+        >
         <activity
             android:name=".MainActivity"
             android:label="@string/app_name" 
-            android:screenOrientation="portrait" >
+            android:screenOrientation="portrait"
+            >
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 

res/layout/about.xml

@@ -4,7 +4,7 @@
 	android:layout_width="fill_parent"
 	android:layout_height="fill_parent">
 
-	<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+	<TextView
 		android:id="@+id/about_text"
 		android:layout_width="fill_parent"
 		android:layout_height="fill_parent"

res/menu/main.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android">
+	<item android:id="@+id/invert"
+		android:title="@string/invert_menu" />
 	<item android:id="@+id/about"
 		android:title="@string/about_menu" />
 </menu>

res/values/strings.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 	<string name="app_name">Just A Damn Compass</string>
+	<string name="invert_menu">Invert</string>
 	<string name="about_menu">About</string>
 	<string name="about_text">
 		This app is just a compass.

src/uk/co/jarofgreen/JustADamnCompass/MainActivity.java

@@ -3,13 +3,18 @@
 import uk.co.jarofgreen.JustADamnCompass.AboutActivity;
 import android.app.Activity;
 import android.os.Bundle;
+import android.preference.PreferenceManager;
 import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
+import android.content.SharedPreferences.Editor;
 import android.graphics.*;
 import android.hardware.Sensor;
 import android.hardware.SensorEvent;
 import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
+import android.util.Log;
+import android.view.Display;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
@@ -20,26 +25,49 @@ public class MainActivity extends Activity {
 	private SensorManager mSensorManager;
 	private Sensor mSensor;
 	private float[] mValues;            
-
+	private float lastDirection = -360;
+	private float secondLastDirection = -360;
 	private SampleView mView;
+
+	private final int MIN_ROTATION = 2;
 
 	private final SensorEventListener mListener = new SensorEventListener() {
         public void onSensorChanged(SensorEvent event) {
+
             mValues = event.values;
-            if (mView != null) mView.invalidate();
+        	// check for min rotation or jitter
+
+            if(Math.abs(lastDirection - mValues[0]) < MIN_ROTATION || secondLastDirection == mValues[0])
+        		return;
+
+            secondLastDirection = lastDirection;
+            lastDirection = mValues[0];
+
+        	if (mView != null) mView.invalidate();
         }
 
         public void onAccuracyChanged(Sensor sensor, int accuracy) {
         }
     };
+	private int w;
+	private int h;
+	private String TAG = "Compass";
+	private SharedPreferences prefs;
+	private static boolean invert;
 
     @Override    
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         mSensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
         mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION);        
+
+        prefs = PreferenceManager.getDefaultSharedPreferences(this);
+        invert = prefs.getBoolean("invert", false);
+
         mView = new SampleView(this);
+        mView.setBackgroundColor(invert?Color.WHITE:Color.BLACK);
         setContentView(mView);
+
     }
 
     @Override
@@ -56,27 +84,72 @@ protected void onStop() {
 
 
     private class SampleView extends View {
+		private Bitmap backgroundImage;
         private Bitmap compassImage;
+		private int nWidth;
+		private int nHeight;
+		private Matrix matrix = new Matrix();
+		private Matrix rotator = new Matrix();
+		private Bitmap a;
+		private Bitmap b;
 
         public SampleView(Context context) {
             super(context);            
-            compassImage = BitmapFactory.decodeResource(getResources(), R.drawable.compass);
+			if(invert) { 
+    			a = BitmapFactory.decodeResource(getResources(), R.drawable.background);
+    			b = BitmapFactory.decodeResource(getResources(), R.drawable.compass_black);
+			}
+    		else {
+    			a = BitmapFactory.decodeResource(getResources(), R.drawable.background_black);
+    			b = BitmapFactory.decodeResource(getResources(), R.drawable.compass_white);
+    		}           
         }
 
         @Override protected void onDraw(Canvas canvas) {
-            canvas.drawColor(Color.BLACK);
+    		// center
+
+            canvas.translate(0, h/2-nHeight/2);
+
+            // rotate
 
-            int w = canvas.getWidth();
-            int h = canvas.getHeight();
-            int cx = w / 2;
-            int cy = h / 2;
-
-            canvas.translate(cx, cy);
             if (mValues != null) {
-                canvas.rotate(-mValues[0]);
+                rotator.setRotate(-mValues[0], nWidth/2, nHeight/2);
             }
 
-            canvas.drawBitmap(compassImage, -150, -150, null);
+            canvas.drawBitmap(backgroundImage, matrix, null);
+            canvas.drawBitmap(compassImage, rotator, null);
+
+
+        }
+
+        @Override
+        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+
+            // variables
+
+            w = MeasureSpec.getSize(widthMeasureSpec);
+            h = MeasureSpec.getSize(heightMeasureSpec);
+
+            Log.d(TAG,"width: "+w+" height: "+h);
+
+            int mHeight = b.getHeight();
+            int mWidth = b.getWidth();
+
+    		nWidth = w;
+    		nHeight = h;
+
+    		if(mHeight/mWidth > h/w) { // image skinnier than canvas
+    			nWidth = (int) (mWidth*((float)h/(float)mHeight));
+    		}
+    		else { // image fatter than or equal to canvas
+    			nHeight = (int) (mHeight*((float)w/(float)mWidth));
+    		}
+
+    		Log.d(TAG,"image width: "+nWidth+" image height: "+nHeight);
+
+    		backgroundImage = Bitmap.createScaledBitmap(a, nWidth, nHeight, false);
+    		compassImage = Bitmap.createScaledBitmap(b, nWidth, nHeight, false);
 
         }
 
@@ -91,9 +164,20 @@ public boolean onCreateOptionsMenu(Menu menu) {
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
-        switch (item.getItemId()) {
+        Intent i;
+		switch (item.getItemId()) {
         case R.id.about:
-        	Intent i = new Intent(this, AboutActivity.class);            	
+        	i = new Intent(this, AboutActivity.class);            	
+        	startActivity(i);            
+            return true;
+        case R.id.invert:
+        	// invert then restart
+        	Editor e = prefs.edit();
+        	e.putBoolean("invert", invert?false:true);
+        	e.commit();
+
+        	i = new Intent(this, MainActivity.class);
+        	i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
         	startActivity(i);            
             return true;
         default: