Added some code to allow inverted and grayscale modes in WebView

src/acr/browser/lightning/LightningView.java

@@ -10,6 +10,9 @@ import android.app.AlertDialog;
 import android.content.*;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
+import android.graphics.ColorMatrix;
+import android.graphics.ColorMatrixColorFilter;
+import android.graphics.Paint;
 import android.net.MailTo;
 import android.net.Uri;
 import android.net.http.SslError;
@@ -35,34 +38,26 @@ import java.net.*;
 public class LightningView {
 
 	private Title mTitle;
-
 	private WebView mWebView;
-
 	private BrowserController mBrowserController;
-
 	private GestureDetector mGestureDetector;
-
 	private Activity mActivity;
-
 	private WebSettings mSettings;
-
 	private static int API = android.os.Build.VERSION.SDK_INT;
-
 	private static String mHomepage;
-
 	private static String mDefaultUserAgent;
-
 	private static Bitmap mWebpageBitmap;
-
 	private static SharedPreferences mPreferences;
-
 	private static boolean mWideViewPort;
-
 	private AdBlock mAdBlock;
-
 	private boolean isForegroundTab;
-
 	private IntentUtils mIntentUtils;
+	private Paint mPaint = new Paint();
+	private static final float[] mNegativeColorArray = { -1.0f, 0, 0, 0, 255, // red
+			0, -1.0f, 0, 0, 255, // green
+			0, 0, -1.0f, 0, 255, // blue
+			0, 0, 0, 1.0f, 0 // alpha
+	};
 
 	@SuppressWarnings("deprecation")
 	@SuppressLint("NewApi")
@@ -88,6 +83,8 @@ public class LightningView {
 		mWebView.setAnimationCacheEnabled(false);
 		mWebView.setDrawingCacheEnabled(true);
 		mWebView.setBackgroundColor(activity.getResources().getColor(android.R.color.white));
+		mWebView.setBackground(null);
+
 		if (API > 15) {
 			mWebView.getRootView().setBackground(null);
 		} else {
@@ -142,7 +139,7 @@ public class LightningView {
 			if (!url.trim().isEmpty()) {
 				mWebView.loadUrl(url);
 			} else {
-				//don't load anything, the user is looking for a blank tab
+				// don't load anything, the user is looking for a blank tab
 			}
 		} else {
 			if (mHomepage.startsWith("about:home")) {
@@ -358,6 +355,7 @@ public class LightningView {
 	@SuppressWarnings("deprecation")
 	@SuppressLint({ "SetJavaScriptEnabled", "NewApi" })
 	public void initializeSettings(WebSettings settings, Context context) {
+		this.setNormalRendering();
 		if (API < 18) {
 			settings.setAppCacheMaxSize(Long.MAX_VALUE);
 		}
@@ -427,6 +425,33 @@ public class LightningView {
 		}
 	}
 
+	public void setHardwareRendering() {
+		mWebView.setLayerType(View.LAYER_TYPE_HARDWARE, mPaint);
+	}
+
+	public void setNormalRendering() {
+		mWebView.setLayerType(View.LAYER_TYPE_NONE, mPaint);
+	}
+
+	public void setColorMode(int mode) {
+		switch (mode) {
+			case 0:
+				mPaint.setColorFilter(null);
+				break;
+			case 1:
+				ColorMatrixColorFilter filterInvert = new ColorMatrixColorFilter(
+						mNegativeColorArray);
+				mPaint.setColorFilter(filterInvert);
+				break;
+			case 2:
+				ColorMatrix cm = new ColorMatrix();
+				cm.setSaturation(0);
+				ColorMatrixColorFilter filterGray = new ColorMatrixColorFilter(cm);
+				mPaint.setColorFilter(filterGray);
+				break;
+		}
+	}
+
 	public synchronized void pauseTimers() {
 		if (mWebView != null) {
 			mWebView.pauseTimers();