Develop Reference

About the "onDoubleTap" function in android developer sample "InteractiveChart",

I want to learn how to handle the image and gesture function in android.
So I read the sample "InteractiveChart" under "Animating a Scroll Gesture" section in Android developer website.
While I read about "onDoubleTap" method in InteractiveLineGraphView.java.
#Override
public boolean onDoubleTap(MotionEvent e) {
mZoomer.forceFinished(true);
if (hitTest(e.getX(), e.getY(), mZoomFocalPoint)) {
mZoomer.startZoom(ZOOM_AMOUNT);
}
ViewCompat.postInvalidateOnAnimation(InteractiveLineGraphView.this);
return true;
}
I checked the code of Zoomer.
It mainly calls DecelerateInterpolator method and set some variables.
I wonder how can "Zoomer" achieve the double tap zoom function.
Does "DecelerateInterpolator" do the work? Or I just missed something?
public class Zoomer {
/**
* The interpolator, used for making zooms animate 'naturally.'
*/
private Interpolator mInterpolator;
/**
* The total animation duration for a zoom.
*/
private int mAnimationDurationMillis;
/**
* Whether or not the current zoom has finished.
*/
private boolean mFinished = true;
/**
* The current zoom value; computed by {#link #computeZoom()}.
*/
private float mCurrentZoom;
/**
* The time the zoom started, computed using {#link android.os.SystemClock#elapsedRealtime()}.
*/
private long mStartRTC;
/**
* The destination zoom factor.
*/
private float mEndZoom;
public Zoomer(Context context) {
mInterpolator = new DecelerateInterpolator();
mAnimationDurationMillis = context.getResources().getInteger(
android.R.integer.config_shortAnimTime);
}
/**
* Forces the zoom finished state to the given value. Unlike {#link #abortAnimation()}, the
* current zoom value isn't set to the ending value.
*
* #see android.widget.Scroller#forceFinished(boolean)
*/
public void forceFinished(boolean finished) {
mFinished = finished;
}
/**
* Aborts the animation, setting the current zoom value to the ending value.
*
* #see android.widget.Scroller#abortAnimation()
*/
public void abortAnimation() {
mFinished = true;
mCurrentZoom = mEndZoom;
}
/**
* Starts a zoom from 1.0 to (1.0 + endZoom). That is, to zoom from 100% to 125%, endZoom should
* by 0.25f.
*
* #see android.widget.Scroller#startScroll(int, int, int, int)
*/
public void startZoom(float endZoom) {
mStartRTC = SystemClock.elapsedRealtime();
mEndZoom = endZoom;
mFinished = false;
mCurrentZoom = 1f;
}
/**
* Computes the current zoom level, returning true if the zoom is still active and false if the
* zoom has finished.
*
* #see android.widget.Scroller#computeScrollOffset()
*/
public boolean computeZoom() {
if (mFinished) {
return false;
}
long tRTC = SystemClock.elapsedRealtime() - mStartRTC;
if (tRTC >= mAnimationDurationMillis) {
mFinished = true;
mCurrentZoom = mEndZoom;
return false;
}
float t = tRTC * 1f / mAnimationDurationMillis;
mCurrentZoom = mEndZoom * mInterpolator.getInterpolation(t);
return true;
}
/**
* Returns the current zoom level.
*
* #see android.widget.Scroller#getCurrX()
*/
public float getCurrZoom() {
return mCurrentZoom;
}
}
Can someone also recommend some great sample about image and gesture handling? From basic to advanced.....Thanks a lot.

The double tap is actually done in InteractiveLineGraphView view itself
#Override
public boolean onDoubleTap(MotionEvent e) {
mZoomer.forceFinished(true);
if (hitTest(e.getX(), e.getY(), mZoomFocalPoint)) {
mZoomer.startZoom(ZOOM_AMOUNT);
}
ViewCompat.postInvalidateOnAnimation(InteractiveLineGraphView.this);
return true;
}
Zoomer is just a helper class holding current zoom level

How to have a auto scrollable TextView

I am trying to have a automatic scroll in android app.
Suppose that, I have xml code like this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="show me the texts"
android:id="#+id/button"/>
<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/text"
android:id="#+id/textView1"/>
</ScrollView>
</LinearLayout>
In this xml code I have a Button on the top of the screen and a TextView which is wrapped by a ScrollView. It means that my TextView is scrollable right now.
It works correctly, because when the user touch the screen and swap down or up, the TextView can be scrolled up and down.
But...
I intend to have a Auto Scrollable TextView and by auto I mean, I need a scrollable TextView which scrolls down about 10dp after 10 seconds.
I know I must use some thread in my application for counting the time but I don't know how to say to TextView scroll down after 10 seconds for example.
any suggestions? Any hint will be appreciated. Thanks

You can use some thing like:
mScrollView.post(new Runnable() {
public void run() {
mScrollView.smoothScrollBy(10, 10);
}
});
Documentation for smoothScrollBy :http://developer.android.com/reference/android/widget/ScrollView.html#smoothScrollBy(int,int)
To execute this task for every 10seconds:
TimerTask fileProcessTask = new TimerTask(){
#Override
public void run() {
//Scrolling here
}
};
Timer tm = new Timer();
tm.schedule(fileProcessTask, 10000L);
Also take a look at this SO Post: https://stackoverflow.com/a/14685729/3326331 , I haven't tried it but you can give it a try.

Create a new Class File and paste the code below.
In your Layout.xml give Reference to EllipsizingTextView rather than using Android TextView.
/*
* Copyright (C) 2011 Micah Hainline
* Copyright (C) 2012 Triposo
* Copyright (C) 2013 Paul Imhoff
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.text.Layout;
import android.text.Layout.Alignment;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.StaticLayout;
import android.text.TextUtils;
import android.text.TextUtils.TruncateAt;
import android.util.AttributeSet;
import android.widget.TextView;
/**
* A {#link android.widget.TextView} that ellipsizes more intelligently. This class supports ellipsizing multiline text through setting {#code android:ellipsize} and {#code android:maxLines}.
*/
public class EllipsizingTextView extends TextView {
private static final CharSequence ELLIPSIS = "\u2026";
private static final Pattern DEFAULT_END_PUNCTUATION = Pattern.compile("[\\.!?,;:\u2026]*$", Pattern.DOTALL);
private final List<EllipsizeListener> mEllipsizeListeners = new ArrayList<EllipsizeListener>();
private EllipsizeStrategy mEllipsizeStrategy;
private boolean isEllipsized;
private boolean isStale;
private boolean programmaticChange;
private CharSequence mFullText;
private int mMaxLines;
private float mLineSpacingMult = 1.0f;
private float mLineAddVertPad = 0.0f;
/**
* The end punctuation which will be removed when appending {#link #ELLIPSIS}.
*/
private Pattern mEndPunctPattern;
public EllipsizingTextView(Context context) {
this(context, null);
}
public EllipsizingTextView(Context context, AttributeSet attrs) {
this(context, attrs, android.R.attr.textViewStyle);
}
public EllipsizingTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray a = context.obtainStyledAttributes(attrs, new int[] { android.R.attr.maxLines, android.R.attr.ellipsize }, defStyle, 0);
setMaxLines(a.getInt(0, Integer.MAX_VALUE));
a.recycle();
setEndPunctuationPattern(DEFAULT_END_PUNCTUATION);
}
public void setEndPunctuationPattern(Pattern pattern) {
mEndPunctPattern = pattern;
}
public void addEllipsizeListener(EllipsizeListener listener) {
if (listener == null)
throw new NullPointerException();
mEllipsizeListeners.add(listener);
}
public void removeEllipsizeListener(EllipsizeListener listener) {
mEllipsizeListeners.remove(listener);
}
public boolean isEllipsized() {
return isEllipsized;
}
/**
* #return The maximum number of lines displayed in this {#link android.widget.TextView}.
*/
#SuppressLint("Override")
public int getMaxLines() {
return mMaxLines;
}
#Override
public void setMaxLines(int maxLines) {
super.setMaxLines(maxLines);
mMaxLines = maxLines;
isStale = true;
}
#Override
public boolean isFocused() {
return true;
}
/**
* Determines if the last fully visible line is being ellipsized.
*
* #return {#code true} if the last fully visible line is being ellipsized; otherwise, returns {#code false}.
*/
public boolean ellipsizingLastFullyVisibleLine() {
return mMaxLines == Integer.MAX_VALUE;
}
#Override
public void setLineSpacing(float add, float mult) {
mLineAddVertPad = add;
mLineSpacingMult = mult;
super.setLineSpacing(add, mult);
}
#Override
public void setText(CharSequence text, BufferType type) {
if (!programmaticChange) {
mFullText = text;
isStale = true;
}
super.setText(text, type);
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
if (ellipsizingLastFullyVisibleLine())
isStale = true;
}
#Override
public void setPadding(int left, int top, int right, int bottom) {
super.setPadding(left, top, right, bottom);
if (ellipsizingLastFullyVisibleLine())
isStale = true;
}
#Override
protected void onDraw(Canvas canvas) {
if (isStale)
resetText();
super.onDraw(canvas);
}
/**
* Sets the ellipsized text if appropriate.
*/
private void resetText() {
int maxLines = getMaxLines();
CharSequence workingText = mFullText;
boolean ellipsized = false;
if (maxLines != -1) {
if (mEllipsizeStrategy == null)
setEllipsize(null);
workingText = mEllipsizeStrategy.processText(mFullText);
ellipsized = !mEllipsizeStrategy.isInLayout(mFullText);
}
if (!workingText.equals(getText())) {
programmaticChange = true;
try {
setText(workingText);
} finally {
programmaticChange = false;
}
}
isStale = false;
if (ellipsized != isEllipsized) {
isEllipsized = ellipsized;
for (EllipsizeListener listener : mEllipsizeListeners) {
listener.ellipsizeStateChanged(ellipsized);
}
}
}
/**
* Causes words in the text that are longer than the view is wide to be ellipsized instead of broken in the middle. Use {#code null} to turn off ellipsizing.
*
* #param where
* part of text to ellipsize
*/
#Override
public void setEllipsize(TruncateAt where) {
if (where == null) {
mEllipsizeStrategy = new EllipsizeNoneStrategy();
return;
}
switch (where) {
case END:
mEllipsizeStrategy = new EllipsizeEndStrategy();
break;
case START:
mEllipsizeStrategy = new EllipsizeStartStrategy();
break;
case MIDDLE:
mEllipsizeStrategy = new EllipsizeMiddleStrategy();
break;
case MARQUEE:
super.setEllipsize(where);
isStale = false;
default:
mEllipsizeStrategy = new EllipsizeNoneStrategy();
break;
}
}
/**
* A listener that notifies when the ellipsize state has changed.
*/
public interface EllipsizeListener {
void ellipsizeStateChanged(boolean ellipsized);
}
/**
* A base class for an ellipsize strategy.
*/
private abstract class EllipsizeStrategy {
/**
* Returns ellipsized text if the text does not fit inside of the layout; otherwise, returns the full text.
*
* #param text
* text to process
* #return Ellipsized text if the text does not fit inside of the layout; otherwise, returns the full text.
*/
public CharSequence processText(CharSequence text) {
return !isInLayout(text) ? createEllipsizedText(text) : text;
}
/**
* Determines if the text fits inside of the layout.
*
* #param text
* text to fit
* #return {#code true} if the text fits inside of the layout; otherwise, returns {#code false}.
*/
public boolean isInLayout(CharSequence text) {
Layout layout = createWorkingLayout(text);
return layout.getLineCount() <= getLinesCount();
}
/**
* Creates a working layout with the given text.
*
* #param workingText
* text to create layout with
* #return {#link android.text.Layout} with the given text.
*/
protected Layout createWorkingLayout(CharSequence workingText) {
return new StaticLayout(workingText, getPaint(), getWidth() - getCompoundPaddingLeft() - getCompoundPaddingRight(), Alignment.ALIGN_NORMAL, mLineSpacingMult, mLineAddVertPad, false /* includepad */);
}
/**
* Get how many lines of text we are allowed to display.
*/
protected int getLinesCount() {
if (ellipsizingLastFullyVisibleLine()) {
int fullyVisibleLinesCount = getFullyVisibleLinesCount();
return fullyVisibleLinesCount == -1 ? 1 : fullyVisibleLinesCount;
} else {
return mMaxLines;
}
}
/**
* Get how many lines of text we can display so their full height is visible.
*/
protected int getFullyVisibleLinesCount() {
Layout layout = createWorkingLayout("");
int height = getHeight() - getCompoundPaddingTop() - getCompoundPaddingBottom();
int lineHeight = layout.getLineBottom(0);
return height / lineHeight;
}
/**
* Creates ellipsized text from the given text.
*
* #param fullText
* text to ellipsize
* #return Ellipsized text
*/
protected abstract CharSequence createEllipsizedText(CharSequence fullText);
}
/**
* An {#link EllipsizingTextView.EllipsizeStrategy} that does not ellipsize text.
*/
private class EllipsizeNoneStrategy extends EllipsizeStrategy {
#Override
protected CharSequence createEllipsizedText(CharSequence fullText) {
return fullText;
}
}
/**
* An {#link EllipsizingTextView.EllipsizeStrategy} that ellipsizes text at the end.
*/
private class EllipsizeEndStrategy extends EllipsizeStrategy {
#Override
protected CharSequence createEllipsizedText(CharSequence fullText) {
Layout layout = createWorkingLayout(fullText);
int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
int textLength = fullText.length();
int cutOffLength = textLength - cutOffIndex;
if (cutOffLength < ELLIPSIS.length())
cutOffLength = ELLIPSIS.length();
String workingText = TextUtils.substring(fullText, 0, textLength - cutOffLength).trim();
String strippedText = stripEndPunctuation(workingText);
while (!isInLayout(strippedText + ELLIPSIS)) {
int lastSpace = workingText.lastIndexOf(' ');
if (lastSpace == -1)
break;
workingText = workingText.substring(0, lastSpace).trim();
strippedText = stripEndPunctuation(workingText);
}
workingText = strippedText + ELLIPSIS;
SpannableStringBuilder dest = new SpannableStringBuilder(workingText);
if (fullText instanceof Spanned) {
TextUtils.copySpansFrom((Spanned) fullText, 0, workingText.length(), null, dest, 0);
}
return dest;
}
/**
* Strips the end punctuation from a given text according to {#link #mEndPunctPattern}.
*
* #param workingText
* text to strip end punctuation from
* #return Text without end punctuation.
*/
public String stripEndPunctuation(CharSequence workingText) {
return mEndPunctPattern.matcher(workingText).replaceFirst("");
}
}
/**
* An {#link EllipsizingTextView.EllipsizeStrategy} that ellipsizes text at the start.
*/
private class EllipsizeStartStrategy extends EllipsizeStrategy {
#Override
protected CharSequence createEllipsizedText(CharSequence fullText) {
Layout layout = createWorkingLayout(fullText);
int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
int textLength = fullText.length();
int cutOffLength = textLength - cutOffIndex;
if (cutOffLength < ELLIPSIS.length())
cutOffLength = ELLIPSIS.length();
String workingText = TextUtils.substring(fullText, cutOffLength, textLength).trim();
while (!isInLayout(ELLIPSIS + workingText)) {
int firstSpace = workingText.indexOf(' ');
if (firstSpace == -1)
break;
workingText = workingText.substring(firstSpace, workingText.length()).trim();
}
workingText = ELLIPSIS + workingText;
SpannableStringBuilder dest = new SpannableStringBuilder(workingText);
if (fullText instanceof Spanned) {
TextUtils.copySpansFrom((Spanned) fullText, textLength - workingText.length(), textLength, null, dest, 0);
}
return dest;
}
}
/**
* An {#link EllipsizingTextView.EllipsizeStrategy} that ellipsizes text in the middle.
*/
private class EllipsizeMiddleStrategy extends EllipsizeStrategy {
#Override
protected CharSequence createEllipsizedText(CharSequence fullText) {
Layout layout = createWorkingLayout(fullText);
int cutOffIndex = layout.getLineEnd(mMaxLines - 1);
int textLength = fullText.length();
int cutOffLength = textLength - cutOffIndex;
if (cutOffLength < ELLIPSIS.length())
cutOffLength = ELLIPSIS.length();
cutOffLength += cutOffIndex % 2; // Make it even.
String firstPart = TextUtils.substring(fullText, 0, textLength / 2 - cutOffLength / 2).trim();
String secondPart = TextUtils.substring(fullText, textLength / 2 + cutOffLength / 2, textLength).trim();
while (!isInLayout(firstPart + ELLIPSIS + secondPart)) {
int lastSpaceFirstPart = firstPart.lastIndexOf(' ');
int firstSpaceSecondPart = secondPart.indexOf(' ');
if (lastSpaceFirstPart == -1 || firstSpaceSecondPart == -1)
break;
firstPart = firstPart.substring(0, lastSpaceFirstPart).trim();
secondPart = secondPart.substring(firstSpaceSecondPart, secondPart.length()).trim();
}
SpannableStringBuilder firstDest = new SpannableStringBuilder(firstPart);
SpannableStringBuilder secondDest = new SpannableStringBuilder(secondPart);
if (fullText instanceof Spanned) {
TextUtils.copySpansFrom((Spanned) fullText, 0, firstPart.length(), null, firstDest, 0);
TextUtils.copySpansFrom((Spanned) fullText, textLength - secondPart.length(), textLength, null, secondDest, 0);
}
return TextUtils.concat(firstDest, ELLIPSIS, secondDest);
}
}
}

ActionBar setIcon with Font-Awesome

Is it possible to set an Icon in ActionBar through setIcon method (that accept drawable or Resource id) with a "Text" using AwesomeFont?
Should I create a Drawable or something like that? In Drawable what should I Create?
EDIT
public class AwesomeTextView extends TextView {
private static Typeface fontAwesome;
public AwesomeTextView(Context context, AttributeSet attrs) {
super(context, attrs);
if (fontAwesome == null) {
fontAwesome = Typeface.createFromAsset(context.getAssets(), "fonts/fontawesome-webfont.ttf");
}
setTypeface(fontAwesome);
}
}
So I had created an AwesomeTextView that uses font-awesome, Is there a way to make an AwesomeTextView as drawable?

I made a repo to easily add font awesome icons to your android project
https://github.com/bperin/FontAwesomeAndroid
If you're trying to add these in an action bar you'll probably need to make a custom layout via XML

Yes, you need to create a Drawable and draw the icon. You could take a look at the TextDrawable project on github. You can modify it such that Font-Awesome is used as the typeface.
Make sure that you bundle the font along with the project.

Here's a complete guide on how to set Icon with FontAwesome with setIcon() method.
http://blog.incognitech.in/font-awesome-in-android
UPDATE:
FontManager Class
public class FontAwesomeManager {
public static final String ROOT = "fonts/";
public static final String FONTAWESOME = ROOT + "fontawesome-webfont.ttf";
public static Typeface getTypeface(Context context, String font) {
return Typeface.createFromAsset(context.getAssets(), font);
}
}
TextDrawable class
package in.incognitech.reminder.util;
/**
* Copyright (c) 2012 Wireless Designs, LLC
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Rect;
import android.graphics.Typeface;
import android.graphics.drawable.Drawable;
import android.text.Layout;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.TypedValue;
/**
* A Drawable object that draws text.
* A TextDrawable accepts most of the same parameters that can be applied to
* {#link android.widget.TextView} for displaying and formatting text.
*
* Optionally, a {#link Path} may be supplied on which to draw the text.
*
* A TextDrawable has an intrinsic size equal to that required to draw all
* the text it has been supplied, when possible. In cases where a {#link Path}
* has been supplied, the caller must explicitly call
* {#link #setBounds(android.graphics.Rect) setBounds()} to provide the Drawable
* size based on the Path constraints.
*/
public class TextDrawable extends Drawable {
/* Platform XML constants for typeface */
private static final int SANS = 1;
private static final int SERIF = 2;
private static final int MONOSPACE = 3;
/* Resources for scaling values to the given device */
private Resources mResources;
/* Paint to hold most drawing primitives for the text */
private TextPaint mTextPaint;
/* Layout is used to measure and draw the text */
private StaticLayout mTextLayout;
/* Alignment of the text inside its bounds */
private Layout.Alignment mTextAlignment = Layout.Alignment.ALIGN_NORMAL;
/* Optional path on which to draw the text */
private Path mTextPath;
/* Stateful text color list */
private ColorStateList mTextColors;
/* Container for the bounds to be reported to widgets */
private Rect mTextBounds;
/* Text string to draw */
private CharSequence mText = "";
/* Attribute lists to pull default values from the current theme */
private static final int[] themeAttributes = {
android.R.attr.textAppearance
};
private static final int[] appearanceAttributes = {
android.R.attr.textSize,
android.R.attr.typeface,
android.R.attr.textStyle,
android.R.attr.textColor
};
public TextDrawable(Context context) {
super();
//Used to load and scale resource items
mResources = context.getResources();
//Definition of this drawables size
mTextBounds = new Rect();
//Paint to use for the text
mTextPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
mTextPaint.density = mResources.getDisplayMetrics().density;
mTextPaint.setDither(true);
int textSize = 15;
ColorStateList textColor = null;
int styleIndex = -1;
int typefaceIndex = -1;
//Set default parameters from the current theme
TypedArray a = context.getTheme().obtainStyledAttributes(themeAttributes);
int appearanceId = a.getResourceId(0, -1);
a.recycle();
TypedArray ap = null;
if (appearanceId != -1) {
ap = context.obtainStyledAttributes(appearanceId, appearanceAttributes);
}
if (ap != null) {
for (int i=0; i < ap.getIndexCount(); i++) {
int attr = ap.getIndex(i);
switch (attr) {
case 0: //Text Size
textSize = a.getDimensionPixelSize(attr, textSize);
break;
case 1: //Typeface
typefaceIndex = a.getInt(attr, typefaceIndex);
break;
case 2: //Text Style
styleIndex = a.getInt(attr, styleIndex);
break;
case 3: //Text Color
textColor = a.getColorStateList(attr);
break;
default:
break;
}
}
ap.recycle();
}
setTextColor(textColor != null ? textColor : ColorStateList.valueOf(0xFF000000));
setRawTextSize(textSize);
Typeface tf = null;
switch (typefaceIndex) {
case SANS:
tf = Typeface.SANS_SERIF;
break;
case SERIF:
tf = Typeface.SERIF;
break;
case MONOSPACE:
tf = Typeface.MONOSPACE;
break;
}
setTypeface(tf, styleIndex);
}
/**
* Set the text that will be displayed
* #param text Text to display
*/
public void setText(CharSequence text) {
if (text == null) text = "";
mText = text;
measureContent();
}
/**
* Return the text currently being displayed
*/
public CharSequence getText() {
return mText;
}
/**
* Return the current text size, in pixels
*/
public float getTextSize() {
return mTextPaint.getTextSize();
}
/**
* Set the text size. The value will be interpreted in "sp" units
* #param size Text size value, in sp
*/
public void setTextSize(float size) {
setTextSize(TypedValue.COMPLEX_UNIT_SP, size);
}
/**
* Set the text size, using the supplied complex units
* #param unit Units for the text size, such as dp or sp
* #param size Text size value
*/
public void setTextSize(int unit, float size) {
float dimension = TypedValue.applyDimension(unit, size,
mResources.getDisplayMetrics());
setRawTextSize(dimension);
}
/*
* Set the text size, in raw pixels
*/
private void setRawTextSize(float size) {
if (size != mTextPaint.getTextSize()) {
mTextPaint.setTextSize(size);
measureContent();
}
}
/**
* Return the horizontal stretch factor of the text
*/
public float getTextScaleX() {
return mTextPaint.getTextScaleX();
}
/**
* Set the horizontal stretch factor of the text
* #param size Text scale factor
*/
public void setTextScaleX(float size) {
if (size != mTextPaint.getTextScaleX()) {
mTextPaint.setTextScaleX(size);
measureContent();
}
}
/**
* Return the current text alignment setting
*/
public Layout.Alignment getTextAlign() {
return mTextAlignment;
}
/**
* Set the text alignment. The alignment itself is based on the text layout direction.
* For LTR text NORMAL is left aligned and OPPOSITE is right aligned.
* For RTL text, those alignments are reversed.
* #param align Text alignment value. Should be set to one of:
*
* {#link Layout.Alignment#ALIGN_NORMAL},
* {#link Layout.Alignment#ALIGN_NORMAL},
* {#link Layout.Alignment#ALIGN_OPPOSITE}.
*/
public void setTextAlign(Layout.Alignment align) {
if (mTextAlignment != align) {
mTextAlignment = align;
measureContent();
}
}
/**
* Sets the typeface and style in which the text should be displayed.
* Note that not all Typeface families actually have bold and italic
* variants, so you may need to use
* {#link #setTypeface(Typeface, int)} to get the appearance
* that you actually want.
*/
public void setTypeface(Typeface tf) {
if (mTextPaint.getTypeface() != tf) {
mTextPaint.setTypeface(tf);
measureContent();
}
}
/**
* Sets the typeface and style in which the text should be displayed,
* and turns on the fake bold and italic bits in the Paint if the
* Typeface that you provided does not have all the bits in the
* style that you specified.
*
*/
public void setTypeface(Typeface tf, int style) {
if (style > 0) {
if (tf == null) {
tf = Typeface.defaultFromStyle(style);
} else {
tf = Typeface.create(tf, style);
}
setTypeface(tf);
// now compute what (if any) algorithmic styling is needed
int typefaceStyle = tf != null ? tf.getStyle() : 0;
int need = style & ~typefaceStyle;
mTextPaint.setFakeBoldText((need & Typeface.BOLD) != 0);
mTextPaint.setTextSkewX((need & Typeface.ITALIC) != 0 ? -0.25f : 0);
} else {
mTextPaint.setFakeBoldText(false);
mTextPaint.setTextSkewX(0);
setTypeface(tf);
}
}
/**
* Return the current typeface and style that the Paint
* using for display.
*/
public Typeface getTypeface() {
return mTextPaint.getTypeface();
}
/**
* Set a single text color for all states
* #param color Color value such as {#link Color#WHITE} or {#link Color#argb(int, int, int, int)}
*/
public void setTextColor(int color) {
setTextColor(ColorStateList.valueOf(color));
}
/**
* Set the text color as a state list
* #param colorStateList ColorStateList of text colors, such as inflated from an R.color resource
*/
public void setTextColor(ColorStateList colorStateList) {
mTextColors = colorStateList;
updateTextColors(getState());
}
/**
* Optional Path object on which to draw the text. If this is set,
* TextDrawable cannot properly measure the bounds this drawable will need.
* You must call {#link #setBounds(int, int, int, int) setBounds()} before
* applying this TextDrawable to any View.
*
* Calling this method with <code>null</code> will remove any Path currently attached.
*/
public void setTextPath(Path path) {
if (mTextPath != path) {
mTextPath = path;
measureContent();
}
}
/**
* Internal method to take measurements of the current contents and apply
* the correct bounds when possible.
*/
private void measureContent() {
//If drawing to a path, we cannot measure intrinsic bounds
//We must resly on setBounds being called externally
if (mTextPath != null) {
//Clear any previous measurement
mTextLayout = null;
mTextBounds.setEmpty();
} else {
//Measure text bounds
double desired = Math.ceil( Layout.getDesiredWidth(mText, mTextPaint) );
mTextLayout = new StaticLayout(mText, mTextPaint, (int)desired,
mTextAlignment, 1.0f, 0.0f, false);
mTextBounds.set(0, 0, mTextLayout.getWidth(), mTextLayout.getHeight());
}
//We may need to be redrawn
invalidateSelf();
}
/**
* Internal method to apply the correct text color based on the drawable's state
*/
private boolean updateTextColors(int[] stateSet) {
int newColor = mTextColors.getColorForState(stateSet, Color.WHITE);
if (mTextPaint.getColor() != newColor) {
mTextPaint.setColor(newColor);
return true;
}
return false;
}
#Override
protected void onBoundsChange(Rect bounds) {
//Update the internal bounds in response to any external requests
mTextBounds.set(bounds);
}
#Override
public boolean isStateful() {
/*
* The drawable's ability to represent state is based on
* the text color list set
*/
return mTextColors.isStateful();
}
#Override
protected boolean onStateChange(int[] state) {
//Upon state changes, grab the correct text color
return updateTextColors(state);
}
#Override
public int getIntrinsicHeight() {
//Return the vertical bounds measured, or -1 if none
if (mTextBounds.isEmpty()) {
return -1;
} else {
return (mTextBounds.bottom - mTextBounds.top);
}
}
#Override
public int getIntrinsicWidth() {
//Return the horizontal bounds measured, or -1 if none
if (mTextBounds.isEmpty()) {
return -1;
} else {
return (mTextBounds.right - mTextBounds.left);
}
}
#Override
public void draw(Canvas canvas) {
final Rect bounds = getBounds();
final int count = canvas.save();
canvas.translate(bounds.left, bounds.top);
if (mTextPath == null) {
//Allow the layout to draw the text
mTextLayout.draw(canvas);
} else {
//Draw directly on the canvas using the supplied path
canvas.drawTextOnPath(mText.toString(), mTextPath, 0, 0, mTextPaint);
}
canvas.restoreToCount(count);
}
#Override
public void setAlpha(int alpha) {
if (mTextPaint.getAlpha() != alpha) {
mTextPaint.setAlpha(alpha);
}
}
#Override
public int getOpacity() {
return mTextPaint.getAlpha();
}
#Override
public void setColorFilter(ColorFilter cf) {
if (mTextPaint.getColorFilter() != cf) {
mTextPaint.setColorFilter(cf);
}
}
}
Use FontManager & TextDrawable class
// ...
TextDrawable faIcon = new TextDrawable(this);
faIcon.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 20);
faIcon.setTextAlign(Layout.Alignment.ALIGN_CENTER);
faIcon.setTypeface(FontAwesomeManager.getTypeface(this, FontAwesomeManager.FONTAWESOME));
faIcon.setText(getResources().getText(R.string.fa_android));
getActionBar().setIcon(faIcon);
// ...

Level selector using andEngine. Every thing is black?

I started working on AndEngine and I have learnt a lot but i am stuck in creating levels selector for my game. I know this is something to do with getTextureManager() as i went through this when i am trying to attach ITextureRegion to my sprite object, that i solved but this time i am going nowhere for last day.
mainActivity.java
import org.andengine.engine.camera.Camera;
import org.andengine.engine.options.EngineOptions;
import org.andengine.engine.options.ScreenOrientation;
import org.andengine.engine.options.WakeLockOptions;
import org.andengine.engine.options.resolutionpolicy.FillResolutionPolicy;
import org.andengine.entity.scene.Scene;
import org.andengine.entity.scene.background.Background;
import org.andengine.opengl.font.FontFactory;
import org.andengine.opengl.texture.ITexture;
import org.andengine.opengl.texture.TextureManager;
import org.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlas;
import org.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlasTextureRegionFactory;
import org.andengine.opengl.texture.atlas.bitmap.BuildableBitmapTextureAtlas;
import org.andengine.opengl.texture.atlas.bitmap.source.IBitmapTextureAtlasSource;
import org.andengine.opengl.texture.atlas.buildable.builder.BlackPawnTextureAtlasBuilder;
import org.andengine.opengl.texture.atlas.buildable.builder.ITextureAtlasBuilder.TextureAtlasBuilderException;
import org.andengine.opengl.texture.region.ITextureRegion;
import org.andengine.opengl.texture.region.TextureRegion;
import org.andengine.ui.activity.SimpleBaseGameActivity;
import org.andengine.util.color.Color;
import android.graphics.Typeface;
import android.util.Log;
public class Main_Activity extends SimpleBaseGameActivity {
EngineOptions engine;
Camera mCamera;
private static final int WIDTH = 800;
private static final int HEIGHT = 480;
LevelSelector ls;
Scene mScene;
public org.andengine.opengl.font.Font mFont;
ITextureRegion mTextureRegion;
#Override
public EngineOptions onCreateEngineOptions() {
mCamera = new Camera(0, 0, WIDTH, HEIGHT);
engine = new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED, new FillResolutionPolicy(), mCamera);
engine.setWakeLockOptions(WakeLockOptions.SCREEN_ON);
return engine;
}
#Override
protected void onCreateResources() {
BuildableBitmapTextureAtlas mBitmapTextureAtlas = new BuildableBitmapTextureAtlas(this.getTextureManager() ,32 , 32);
mTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mBitmapTextureAtlas, this, "marble.png");
try {
mBitmapTextureAtlas.build(new BlackPawnTextureAtlasBuilder<IBitmapTextureAtlasSource, BitmapTextureAtlas>(0, 1, 1));
mBitmapTextureAtlas.load();
} catch (TextureAtlasBuilderException e) {
Log.e("", ""+e);
}
this.mFont = FontFactory.create(this.getFontManager(), this.getTextureManager(), 256, 256, Typeface.create(Typeface.DEFAULT, Typeface.BOLD), 32);
this.mFont.load();
}
#Override
protected Scene onCreateScene() {
mScene = new Scene();
mScene.setBackground(new Background(0.09804f, 0.6274f, 0.8784f));
ls = new LevelSelector(5, 2, WIDTH, HEIGHT, mScene, mEngine);
ls.createTiles(mTextureRegion, mFont);
ls.show();
return mScene;
}
}
LayerSelector.java
import org.andengine.engine.options.EngineOptions;
import org.andengine.entity.Entity;
import org.andengine.entity.scene.Scene;
import org.andengine.entity.sprite.Sprite;
import org.andengine.entity.text.Text;
import org.andengine.input.touch.TouchEvent;
import org.andengine.opengl.font.Font;
import org.andengine.opengl.texture.region.ITextureRegion;
import org.andengine.opengl.texture.region.TextureRegion;
import android.service.wallpaper.WallpaperService.Engine;
public class LevelSelector extends Entity {
/* Level selector layer properties */
private final int COLUMNS = 6;
private final int ROWS = 6;
/* Level selector tile properties */
private final int TILE_DIMENSION = 50;
private final int TILE_PADDING = 15;
private final Scene mScene;
private final org.andengine.engine.Engine mEngine;
/*
* The mChapter variable can allow each LevelSelector object to contain
* level tiles which begin levels in different chapters.
*/
private final int mChapter;
/* Variable containing the current max level unlocked */
private final int mMaxLevel;
/* Camera width and height are needed for the layout */
private final int mCameraWidth;
private final int mCameraHeight;
/* Initial x/y coordinates used for tile positioning */
private final float mInitialX;
private final float mInitialY;
/*
* Variable which defines whether the LevelSelector is hidden or visible
*/
private boolean mHidden = true;
/**
* The LevelSelector object can be used to display a grid of level tiles for
* user selection.
*
* #param pMaxLevel
* Current max unlocked level.
* #param pChapter
* Chapter/world number of this particular LevelSelector.
* #param pCameraWidth
* Camera object's width value.
* #param pCameraHeight
* Camera object's height value.
* #param pScene
* The Scene in which the LevelSelector will be displayed on.
* #param pEngine
* AndEngine's mEngine object.
*/
public LevelSelector(final int pMaxLevel, final int pChapter,
final int pCameraWidth, final int pCameraHeight,
final Scene pScene, final org.andengine.engine.Engine pEngine) {
/* Initialize member variables */
this.mScene = pScene;
this.mEngine = pEngine;
this.mChapter = pChapter;
this.mMaxLevel = pMaxLevel;
this.mCameraWidth = pCameraWidth;
this.mCameraHeight = pCameraHeight;
/*
* Obtain the initial tile's X coordinate by subtracting half of the
* entire level selector width including all tiles and padding from the
* center of the Scene
*/
final float halfLevelSelectorWidth = ((TILE_DIMENSION * COLUMNS) + TILE_PADDING
* (COLUMNS - 1)) * 0.5f;
this.mInitialX = (this.mCameraWidth * 0.5f) - halfLevelSelectorWidth;
/* Same math as above applies to the Y coordinate */
final float halfLevelSelectorHeight = ((TILE_DIMENSION * ROWS) + TILE_PADDING
* (ROWS - 1)) * 0.5f;
this.mInitialY = (this.mCameraHeight * 0.5f) + halfLevelSelectorHeight;
mEngine.getTextureManager();
}
/**
* Create the level tiles with a customized ITextureRegion representation as
* well as a customized Font.
*
* #param pTextureRegion
* The ITextureRegion to supply each of the level tiles.
* #param pFont
* The Font to be displayed by Text written on the tiles,
* specifying tile level number for example.
*/
public void createTiles(final ITextureRegion pTextureRegion,
final org.andengine.opengl.font.Font pFont) {
/* Temp coordinates for placing level tiles */
float tempX = this.mInitialX + TILE_DIMENSION * 0.5f;
float tempY = this.mInitialY - TILE_DIMENSION * 0.5f;
/* Current level of the tile to be placed */
int currentTileLevel = 1;
/*
* Loop through the Rows, adjusting tempY coordinate after each
* iteration
*/
for (int i = 0; i < ROWS; i++) {
/*
* Loop through the column positions, placing a LevelTile in each
* column
*/
for (int o = 0; o < COLUMNS; o++) {
final boolean locked;
/* Determine whether the current tile is locked or not */
if (currentTileLevel <= mMaxLevel) {
locked = false;
} else {
locked = true;
}
/* Create a level tile */
LevelTile levelTile = new LevelTile(tempX, tempY, locked,
currentTileLevel, pTextureRegion, pFont);
/*
* Attach the level tile's text based on the locked and
* currentTileLevel variables pass to its constructor
*/
levelTile.attachText();
/* Register & Attach the levelTile object to the LevelSelector */
mScene.registerTouchArea(levelTile);
this.attachChild(levelTile);
/* Increment the tempX coordinate to the next column */
tempX = tempX + TILE_DIMENSION + TILE_PADDING;
/* Increment the level tile count */
currentTileLevel++;
}
/* Reposition the tempX coordinate back to the first row (far left) */
tempX = mInitialX + TILE_DIMENSION * 0.5f;
/* Reposition the tempY coordinate for the next row to apply tiles */
tempY = tempY - TILE_DIMENSION - TILE_PADDING;
}
}
/**
* Display the LevelSelector on the Scene.
*/
public void show() {
/* Register as non-hidden, allowing touch events */
mHidden = false;
/* Attach the LevelSelector the the Scene if it currently has no parent */
if (!this.hasParent()) {
mScene.attachChild(this);
}
/* Set the LevelSelector to visible */
this.setVisible(true);
}
/**
* Hide the LevelSelector on the Scene.
*/
public void hide() {
/* Register as hidden, disallowing touch events */
mHidden = true;
/* Remove the LevelSelector from view */
this.setVisible(false);
}
public class LevelTile extends Sprite {
/*
* The LevelTile should keep track of level number and lock status. Feel
* free to add additional data within level tiles
*/
private final boolean mIsLocked;
private final int mLevelNumber;
private final org.andengine.opengl.font.Font mFont;
private Text mTileText;
/*
* Each level tile will be sized according to the constant
* TILE_DIMENSION within the LevelSelector class
*/
public LevelTile(float pX, float pY, boolean pIsLocked,
int pLevelNumber, ITextureRegion pTextureRegion, org.andengine.opengl.font.Font pFont) {
super(pX, pY, LevelSelector.this.TILE_DIMENSION,
LevelSelector.this.TILE_DIMENSION, pTextureRegion,
LevelSelector.this.mEngine.getVertexBufferObjectManager());
/* Initialize the necessary variables for the LevelTile */
this.mFont = pFont;
this.mIsLocked = pIsLocked;
this.mLevelNumber = pLevelNumber;
}
/* Method used to obtain whether or not this level tile represents a
* level which is currently locked */
public boolean isLocked() {
return this.mIsLocked;
}
/* Method used to obtain this specific level tiles level number */
public int getLevelNumber() {
return this.mLevelNumber;
}
/*
* Attach the LevelTile's text to itself based on whether it's locked or
* not. If not, then the level number will be displayed on the level
* tile.
*/
public void attachText() {
String tileTextString = null;
/* If the tile's text is currently null... */
if (this.mTileText == null) {
/*
* Determine the tile's string based on whether it's locked or
* not
*/
if (this.mIsLocked) {
tileTextString = "Locked";
} else {
tileTextString = String.valueOf(this.mLevelNumber);
}
/* Setup the text position to be placed in the center of the tile */
final float textPositionX = LevelSelector.this.TILE_DIMENSION * 0.5f;
final float textPositionY = textPositionX;
/* Create the tile's text in the center of the tile */
this.mTileText = new Text( textPositionX,
textPositionY, this.mFont,
tileTextString, tileTextString.length(),
LevelSelector.this.mEngine
.getVertexBufferObjectManager());
/* Attach the Text to the LevelTile */
this.attachChild(mTileText);
}
}
#Override
public boolean onAreaTouched(TouchEvent pSceneTouchEvent,
float pTouchAreaLocalX, float pTouchAreaLocalY) {
/* If the LevelSelector is not hidden, proceed to execute the touch
* event */
if (!LevelSelector.this.mHidden) {
/* If a level tile is initially pressed down on */
if (pSceneTouchEvent.isActionDown()) {
/* If this level tile is locked... */
if (this.mIsLocked) {
/* Tile Locked event... */
LevelSelector.this.mScene.getBackground().setColor(
org.andengine.util.color.Color.RED);
} else {
/* Tile unlocked event... This event would likely prompt
* level loading but without getting too complicated we
* will simply set the Scene's background color to green */
LevelSelector.this.mScene.getBackground().setColor(
org.andengine.util.color.Color.GREEN);
/**
* Example level loading:
* LevelSelector.this.hide();
* SceneManager.loadLevel(this.mLevelNumber);
*/
}
return true;
}
}
return super.onAreaTouched(pSceneTouchEvent, pTouchAreaLocalX,
pTouchAreaLocalY);
}
}
}
FYI, this code belongs to code bundle in Android game development using AndEngine cookbook.
I have edited few variables like font and engine , but i have't changed the logic or flow of program.
Now when I run this I get the below screen

Alright i solved my problem, its was the padding i was using, it should't be there.
try {
mBitmapTextureAtlas.build(new BlackPawnTextureAtlasBuilder<IBitmapTextureAtlasSource, BitmapTextureAtlas>(0, 1, 1));
mBitmapTextureAtlas.load();
} catch (TextureAtlasBuilderException e) {
Log.e("", ""+e);
}
it should be
try {
mBitmapTextureAtlas.build(new BlackPawnTextureAtlasBuilder<IBitmapTextureAtlasSource, BitmapTextureAtlas>(0, 0, 0));
mBitmapTextureAtlas.load();
} catch (TextureAtlasBuilderException e) {
Log.e("", ""+e);
}

Live Wallpaper Tutorial

I am trying to do the following from a live wallpaper tutorial I found here.
/**
* Do the actual drawing stuff
*/
private void doDraw(Canvas canvas) {
Bitmap b = BitmapFactory.decodeResource(context.getResources(), IMAGES[current]);
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(b, 0, 0, null);
Log.d(TAG, "Drawing finished.");
}
/**
* Update the animation, sprites or whatever.
* If there is nothing to animate set the wait
* attribute of the thread to true
*/
private void updatePhysics() {
// if nothing was updated :
// this.wait = true;
if(previousTime - System.currentTimeMillis() >= 41) { //24 FPS
current = current < IMAGES.length ? current++ : 0;
}
Log.d(TAG, "Updated physics.");
}
But it doesn't seem to work. What am I doing wrong. The "Drawing finished." and "Updated physics." messages are getting printed. But I see the first image only. I'm testing it on the emulator.
Any help would be appreciated. Thanks

I have worked out a simple sample live wallpaper where the color shift over time. Maybe you can use this as a starting point:
package com.cmwmobile.android.samples;
import android.graphics.Canvas;
import android.os.Handler;
import android.service.wallpaper.WallpaperService;
import android.view.SurfaceHolder;
/**
* The SampleLiveWallpaperService class is responsible for showing the
* animation and is an interface to android.
* #author Casper Wakkers - www.cmwmobile.com
*/
public class SampleLiveWallpaperService extends WallpaperService {
private Handler handler = null;
/**
* Inner class representing the actual implementation of the
* Live Wallpaper {#link Engine}.
*/
private class SampleLiveWallpaperEngine extends Engine {
private boolean visible = false;
private int[] colors = {0, 0, 0} ;
/**
* Runnable implementation for the actual work.
*/
private final Runnable runnableSomething = new Runnable() {
/**
* {#inheritDoc}
*/
public void run() {
drawSomething();
}
};
/**
* The drawSomething method is responsible for drawing the animation.
*/
private void drawSomething() {
final SurfaceHolder holder = getSurfaceHolder();
Canvas canvas = null;
try {
canvas = holder.lockCanvas();
if (canvas != null) {
canvas.drawARGB(200, colors[0], colors[1], colors[2]);
}
updateColors(colors);
}
finally {
if (canvas != null) {
holder.unlockCanvasAndPost(canvas);
}
}
// Reschedule the next redraw.
handler.removeCallbacks(runnableSomething);
if (visible) {
// Play around with the delay for an optimal result.
handler.postDelayed(runnableSomething, 25);
}
}
/**
* Method updateColors updates the colors by increasing the value
* per RGB. The values are reset to zero if the maximum value is
* reached.
* #param colors to be updated.
*/
private void updateColors(int[] colors) {
if (colors[0] < 255) {
colors[0]++;
}
else {
if (colors[1] < 255) {
colors[1]++;
}
else {
if (colors[2] < 255) {
colors[2]++;
}
else {
colors[0] = 0;
colors[1] = 0;
colors[2] = 0;
}
}
}
}
/**
* {#inheritDoc}
*/
public void onDestroy() {
super.onDestroy();
handler.removeCallbacks(runnableSomething);
}
/**
* {#inheritDoc}
*/
public void onVisibilityChanged(boolean visible) {
super.onVisibilityChanged(visible);
this.visible = visible;
if (visible) {
drawSomething();
}
else {
handler.removeCallbacks(runnableSomething);
}
}
}
/**
* Constructor. Creates the {#link Handler}.
*/
public SampleLiveWallpaperService() {
handler = new Handler();
}
/**
* {#inheritDoc}
*/
public Engine onCreateEngine() {
return new SampleLiveWallpaperEngine();
}
}

I created a quick tutorial on my employers blog about using SVG in a Live Wallpaper, check it out if you like.
Part 1 http://blog.infrared5.com/2012/03/android-live-wallpaper/
Part 2 http://blog.infrared5.com/2012/03/android-live-wallpaper-part-2/