Android Tutorial - 2D Graphics : Path

 Draw text along with path

 

package app.Test;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Path.Direction;
import android.os.Bundle;
import android.view.View;

public class appTest extends Activity {
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new GraphicsView(this));
  }
  static public class GraphicsView extends View {
    private static final String QUOTE = "This is a test. This is a demo.";
    private Path circle;
    private Paint cPaint;
    private Paint tPaint;

    public GraphicsView(Context context) {
      super(context);

      int color = Color.argb(127, 255, 0, 255);

      circle = new Path();
      circle.addCircle(150, 150, 100, Direction.CW);

      cPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
      cPaint.setStyle(Paint.Style.STROKE);
      cPaint.setColor(Color.LTGRAY);
      cPaint.setStrokeWidth(3);

      setBackgroundResource(R.drawable.icon);
      
      tPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
      tPaint.setStyle(Paint.Style.FILL_AND_STROKE);
      tPaint.setColor(Color.BLACK);
      tPaint.setTextSize(20f);

    }

    @Override
    protected void onDraw(Canvas canvas) {
      canvas.drawTextOnPath(QUOTE, circle, 0, 20, tPaint);
    }
  }
}



//main.xml

<?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"
   android:background="@drawable/icon">
   <org.example.graphics.Graphics.GraphicsView
      android:id="@+id/graphics"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent" />
</LinearLayout>


//strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="app_name">Graphics</string>

</resources>


//colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
   <color name="mycolor">#7fff00ff</color> 
</resources>

Draw path

 

package app.test;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.os.Bundle;
import android.widget.ImageView;

public class Test extends Activity {
  ImageView drawingImageView;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    drawingImageView = (ImageView) this.findViewById(R.id.DrawingImageView);
    Bitmap bitmap = Bitmap.createBitmap((int) getWindowManager()
        .getDefaultDisplay().getWidth(), (int) getWindowManager()
        .getDefaultDisplay().getHeight(), Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    drawingImageView.setImageBitmap(bitmap);

    // Path

    Paint paint = new Paint();
    paint.setStyle(Paint.Style.STROKE);
    paint.setColor(Color.GREEN);
    Path p = new Path();
    p.moveTo(20, 20);
    p.lineTo(100, 200);
    p.lineTo(200, 100);
    p.lineTo(240, 155);
    p.lineTo(250, 175);
    p.lineTo(20, 20);
    canvas.drawPath(p, paint);

  }
}

Create a Path

 
package app.test;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Typeface;
import android.os.Bundle;
import android.widget.ImageView;

public class Test extends Activity {
  ImageView drawingImageView;
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    drawingImageView = (ImageView) this.findViewById(R.id.DrawingImageView);
    Bitmap bitmap = Bitmap.createBitmap((int) getWindowManager()
        .getDefaultDisplay().getWidth(), (int) getWindowManager()
        .getDefaultDisplay().getHeight(), Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    drawingImageView.setImageBitmap(bitmap);

    Paint paint = new Paint();
    paint.setColor(Color.GREEN);
    paint.setTextSize(20);
    paint.setTypeface(Typeface.DEFAULT);
    Path p = new Path();
    p.moveTo(20, 20);
    p.lineTo(100, 150);
    p.lineTo(200, 220);
    canvas.drawTextOnPath("this is a test", p, 0, 0, paint);
  }
}

Using PathEffect

package app.test;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.ComposePathEffect;
import android.graphics.CornerPathEffect;
import android.graphics.DiscretePathEffect;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PathEffect;
import android.graphics.Picture;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.SweepGradient;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.ArcShape;
import android.graphics.drawable.shapes.OvalShape;
import android.graphics.drawable.shapes.PathShape;
import android.graphics.drawable.shapes.RectShape;
import android.graphics.drawable.shapes.RoundRectShape;
import android.graphics.drawable.shapes.Shape;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;

public class Test extends GraphicsActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new SampleView(this));
  }

  private static class SampleView extends View {
    private ShapeDrawable[] mDrawables;

    private static Shader makeSweep() {
      return new SweepGradient(150, 25, new int[] { 0xFFFF0000,
          0xFF00FF00, 0xFF0000FF, 0xFFFF0000 }, null);
    }

    private static Shader makeLinear() {
      return new LinearGradient(0, 0, 50, 50, new int[] { 0xFFFF0000,
          0xFF00FF00, 0xFF0000FF }, null, Shader.TileMode.MIRROR);
    }

    private static Shader makeTiling() {
      int[] pixels = new int[] { 0xFFFF0000, 0xFF00FF00, 0xFF0000FF, 0 };
      Bitmap bm = Bitmap.createBitmap(pixels, 2, 2,
          Bitmap.Config.ARGB_8888);

      return new BitmapShader(bm, Shader.TileMode.REPEAT,
          Shader.TileMode.REPEAT);
    }

    private static class MyShapeDrawable extends ShapeDrawable {
      private Paint mStrokePaint = new Paint(Paint.ANTI_ALIAS_FLAG);

      public MyShapeDrawable(Shape s) {
        super(s);
        mStrokePaint.setStyle(Paint.Style.STROKE);
      }

      public Paint getStrokePaint() {
        return mStrokePaint;
      }

      @Override
      protected void onDraw(Shape s, Canvas c, Paint p) {
        s.draw(c, p);
        s.draw(c, mStrokePaint);
      }
    }

    public SampleView(Context context) {
      super(context);
      setFocusable(true);

      float[] outerR = new float[] { 12, 12, 12, 12, 0, 0, 0, 0 };
      RectF inset = new RectF(6, 6, 6, 6);
      float[] innerR = new float[] { 12, 12, 0, 0, 12, 12, 0, 0 };

      Path path = new Path();
      path.moveTo(50, 0);
      path.lineTo(0, 50);
      path.lineTo(50, 100);
      path.lineTo(100, 50);
      path.close();

      mDrawables = new ShapeDrawable[7];
      mDrawables[0] = new ShapeDrawable(new RectShape());
      mDrawables[1] = new ShapeDrawable(new OvalShape());
      mDrawables[2] = new ShapeDrawable(new RoundRectShape(outerR, null,
          null));
      mDrawables[3] = new ShapeDrawable(new RoundRectShape(outerR, inset,
          null));
      mDrawables[4] = new ShapeDrawable(new RoundRectShape(outerR, inset,
          innerR));
      mDrawables[5] = new ShapeDrawable(new PathShape(path, 100, 100));
      mDrawables[6] = new MyShapeDrawable(new ArcShape(45, -270));

      mDrawables[0].getPaint().setColor(0xFFFF0000);
      mDrawables[1].getPaint().setColor(0xFF00FF00);
      mDrawables[2].getPaint().setColor(0xFF0000FF);
      mDrawables[3].getPaint().setShader(makeSweep());
      mDrawables[4].getPaint().setShader(makeLinear());
      mDrawables[5].getPaint().setShader(makeTiling());
      mDrawables[6].getPaint().setColor(0x88FF8844);

      PathEffect pe = new DiscretePathEffect(10, 4);
      PathEffect pe2 = new CornerPathEffect(4);
      mDrawables[3].getPaint().setPathEffect(
          new ComposePathEffect(pe2, pe));

      MyShapeDrawable msd = (MyShapeDrawable) mDrawables[6];
      msd.getStrokePaint().setStrokeWidth(4);
    }

    @Override
    protected void onDraw(Canvas canvas) {

      int x = 10;
      int y = 10;
      int width = 300;
      int height = 50;

      for (Drawable dr : mDrawables) {
        dr.setBounds(x, y, x + width, y + height);
        dr.draw(canvas);
        y += height + 5;
      }
    }
  }
}

class GraphicsActivity extends Activity {
  // set to true to test Picture
  private static final boolean TEST_PICTURE = false;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
  }

  @Override
  public void setContentView(View view) {
    if (TEST_PICTURE) {
      ViewGroup vg = new PictureLayout(this);
      vg.addView(view);
      view = vg;
    }

    super.setContentView(view);
  }
}

class PictureLayout extends ViewGroup {
  private final Picture mPicture = new Picture();

  public PictureLayout(Context context) {
    super(context);
  }

  public PictureLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  @Override
  public void addView(View child) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child);
  }

  @Override
  public void addView(View child, int index) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index);
  }

  @Override
  public void addView(View child, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, params);
  }

  @Override
  public void addView(View child, int index, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index, params);
  }

  @Override
  protected LayoutParams generateDefaultLayoutParams() {
    return new LayoutParams(LayoutParams.MATCH_PARENT,
        LayoutParams.MATCH_PARENT);
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    final int count = getChildCount();

    int maxHeight = 0;
    int maxWidth = 0;

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        measureChild(child, widthMeasureSpec, heightMeasureSpec);
      }
    }

    maxWidth += getPaddingLeft() + getPaddingRight();
    maxHeight += getPaddingTop() + getPaddingBottom();

    Drawable drawable = getBackground();
    if (drawable != null) {
      maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
      maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
    }

    setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec),
        resolveSize(maxHeight, heightMeasureSpec));
  }

  private void drawPict(Canvas canvas, int x, int y, int w, int h, float sx,
      float sy) {
    canvas.save();
    canvas.translate(x, y);
    canvas.clipRect(0, 0, w, h);
    canvas.scale(0.5f, 0.5f);
    canvas.scale(sx, sy, w, h);
    canvas.drawPicture(mPicture);
    canvas.restore();
  }

  @Override
  protected void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(mPicture.beginRecording(getWidth(), getHeight()));
    mPicture.endRecording();

    int x = getWidth() / 2;
    int y = getHeight() / 2;

    if (false) {
      canvas.drawPicture(mPicture);
    } else {
      drawPict(canvas, 0, 0, x, y, 1, 1);
      drawPict(canvas, x, 0, x, y, -1, 1);
      drawPict(canvas, 0, y, x, y, 1, -1);
      drawPict(canvas, x, y, x, y, -1, -1);
    }
  }

  @Override
  public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
    location[0] = getLeft();
    location[1] = getTop();
    dirty.set(0, 0, getWidth(), getHeight());
    return getParent();
  }

  @Override
  protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = super.getChildCount();

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        final int childLeft = getPaddingLeft();
        final int childTop = getPaddingTop();
        child.layout(childLeft, childTop,
            childLeft + child.getMeasuredWidth(),
            childTop + child.getMeasuredHeight());

      }
    }
  }
}

Path Effects

package app.test;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ComposePathEffect;
import android.graphics.CornerPathEffect;
import android.graphics.DashPathEffect;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PathDashPathEffect;
import android.graphics.PathEffect;
import android.graphics.Picture;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;

public class Test extends GraphicsActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new SampleView(this));
  }

  private static class SampleView extends View {
    private Paint mPaint;
    private Path mPath;
    private PathEffect[] mEffects;
    private int[] mColors;
    private float mPhase;

    private static PathEffect makeDash(float phase) {
      return new DashPathEffect(new float[] { 15, 5, 8, 5 }, phase);
    }

    private static void makeEffects(PathEffect[] e, float phase) {
      e[0] = null; // no effect
      e[1] = new CornerPathEffect(10);
      e[2] = new DashPathEffect(new float[] { 10, 5, 5, 5 }, phase);
      e[3] = new PathDashPathEffect(makePathDash(), 12, phase,
          PathDashPathEffect.Style.ROTATE);
      e[4] = new ComposePathEffect(e[2], e[1]);
      e[5] = new ComposePathEffect(e[3], e[1]);
    }

    public SampleView(Context context) {
      super(context);
      setFocusable(true);
      setFocusableInTouchMode(true);

      mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
      mPaint.setStyle(Paint.Style.STROKE);
      mPaint.setStrokeWidth(6);

      mPath = makeFollowPath();

      mEffects = new PathEffect[6];

      mColors = new int[] { Color.BLACK, Color.RED, Color.BLUE,
          Color.GREEN, Color.MAGENTA, Color.BLACK };
    }

    @Override
    protected void onDraw(Canvas canvas) {
      canvas.drawColor(Color.WHITE);

      RectF bounds = new RectF();
      mPath.computeBounds(bounds, false);
      canvas.translate(10 - bounds.left, 10 - bounds.top);

      makeEffects(mEffects, mPhase);
      mPhase += 1;
      invalidate();

      for (int i = 0; i < mEffects.length; i++) {
        mPaint.setPathEffect(mEffects[i]);
        mPaint.setColor(mColors[i]);
        canvas.drawPath(mPath, mPaint);
        canvas.translate(0, 28);
      }
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
      switch (keyCode) {
      case KeyEvent.KEYCODE_DPAD_CENTER:
        mPath = makeFollowPath();
        return true;
      }
      return super.onKeyDown(keyCode, event);
    }

    private static Path makeFollowPath() {
      Path p = new Path();
      p.moveTo(0, 0);
      for (int i = 1; i <= 15; i++) {
        p.lineTo(i * 20, (float) Math.random() * 35);
      }
      return p;
    }

    private static Path makePathDash() {
      Path p = new Path();
      p.moveTo(4, 0);
      p.lineTo(0, -4);
      p.lineTo(8, -4);
      p.lineTo(12, 0);
      p.lineTo(8, 4);
      p.lineTo(0, 4);
      return p;
    }
  }
}

class GraphicsActivity extends Activity {
  // set to true to test Picture
  private static final boolean TEST_PICTURE = false;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
  }

  @Override
  public void setContentView(View view) {
    if (TEST_PICTURE) {
      ViewGroup vg = new PictureLayout(this);
      vg.addView(view);
      view = vg;
    }

    super.setContentView(view);
  }
}

class PictureLayout extends ViewGroup {
  private final Picture mPicture = new Picture();

  public PictureLayout(Context context) {
    super(context);
  }

  public PictureLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  @Override
  public void addView(View child) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child);
  }

  @Override
  public void addView(View child, int index) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index);
  }

  @Override
  public void addView(View child, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, params);
  }

  @Override
  public void addView(View child, int index, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index, params);
  }

  @Override
  protected LayoutParams generateDefaultLayoutParams() {
    return new LayoutParams(LayoutParams.MATCH_PARENT,
        LayoutParams.MATCH_PARENT);
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    final int count = getChildCount();

    int maxHeight = 0;
    int maxWidth = 0;

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        measureChild(child, widthMeasureSpec, heightMeasureSpec);
      }
    }

    maxWidth += getPaddingLeft() + getPaddingRight();
    maxHeight += getPaddingTop() + getPaddingBottom();

    Drawable drawable = getBackground();
    if (drawable != null) {
      maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
      maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
    }

    setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec),
        resolveSize(maxHeight, heightMeasureSpec));
  }

  private void drawPict(Canvas canvas, int x, int y, int w, int h, float sx,
      float sy) {
    canvas.save();
    canvas.translate(x, y);
    canvas.clipRect(0, 0, w, h);
    canvas.scale(0.5f, 0.5f);
    canvas.scale(sx, sy, w, h);
    canvas.drawPicture(mPicture);
    canvas.restore();
  }

  @Override
  protected void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(mPicture.beginRecording(getWidth(), getHeight()));
    mPicture.endRecording();

    int x = getWidth() / 2;
    int y = getHeight() / 2;

    if (false) {
      canvas.drawPicture(mPicture);
    } else {
      drawPict(canvas, 0, 0, x, y, 1, 1);
      drawPict(canvas, x, 0, x, y, -1, 1);
      drawPict(canvas, 0, y, x, y, 1, -1);
      drawPict(canvas, x, y, x, y, -1, -1);
    }
  }

  @Override
  public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
    location[0] = getLeft();
    location[1] = getTop();
    dirty.set(0, 0, getWidth(), getHeight());
    return getParent();
  }

  @Override
  protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = super.getChildCount();

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        final int childLeft = getPaddingLeft();
        final int childTop = getPaddingTop();
        child.layout(childLeft, childTop,
            childLeft + child.getMeasuredWidth(),
            childTop + child.getMeasuredHeight());

      }
    }
  }
}

Path Fill Types

package app.test;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Picture;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;

public class Test extends GraphicsActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new SampleView(this));
  }

  private static class SampleView extends View {
    private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private Path mPath;

    public SampleView(Context context) {
      super(context);
      setFocusable(true);
      setFocusableInTouchMode(true);

      mPath = new Path();
      mPath.addCircle(40, 40, 45, Path.Direction.CCW);
      mPath.addCircle(80, 80, 45, Path.Direction.CCW);
    }

    private void showPath(Canvas canvas, int x, int y, Path.FillType ft,
        Paint paint) {
      canvas.save();
      canvas.translate(x, y);
      canvas.clipRect(0, 0, 120, 120);
      canvas.drawColor(Color.WHITE);
      mPath.setFillType(ft);
      canvas.drawPath(mPath, paint);
      canvas.restore();
    }

    @Override
    protected void onDraw(Canvas canvas) {
      Paint paint = mPaint;

      canvas.drawColor(0xFFCCCCCC);

      canvas.translate(20, 20);

      paint.setAntiAlias(true);

      showPath(canvas, 0, 0, Path.FillType.WINDING, paint);
      showPath(canvas, 160, 0, Path.FillType.EVEN_ODD, paint);
      showPath(canvas, 0, 160, Path.FillType.INVERSE_WINDING, paint);
      showPath(canvas, 160, 160, Path.FillType.INVERSE_EVEN_ODD, paint);
    }
  }
}

class GraphicsActivity extends Activity {
  // set to true to test Picture
  private static final boolean TEST_PICTURE = false;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
  }

  @Override
  public void setContentView(View view) {
    if (TEST_PICTURE) {
      ViewGroup vg = new PictureLayout(this);
      vg.addView(view);
      view = vg;
    }

    super.setContentView(view);
  }
}

class PictureLayout extends ViewGroup {
  private final Picture mPicture = new Picture();

  public PictureLayout(Context context) {
    super(context);
  }

  public PictureLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  @Override
  public void addView(View child) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child);
  }

  @Override
  public void addView(View child, int index) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index);
  }

  @Override
  public void addView(View child, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, params);
  }

  @Override
  public void addView(View child, int index, LayoutParams params) {
    if (getChildCount() > 1) {
      throw new IllegalStateException(
          "PictureLayout can host only one direct child");
    }

    super.addView(child, index, params);
  }

  @Override
  protected LayoutParams generateDefaultLayoutParams() {
    return new LayoutParams(LayoutParams.MATCH_PARENT,
        LayoutParams.MATCH_PARENT);
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    final int count = getChildCount();

    int maxHeight = 0;
    int maxWidth = 0;

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        measureChild(child, widthMeasureSpec, heightMeasureSpec);
      }
    }

    maxWidth += getPaddingLeft() + getPaddingRight();
    maxHeight += getPaddingTop() + getPaddingBottom();

    Drawable drawable = getBackground();
    if (drawable != null) {
      maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
      maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
    }

    setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec),
        resolveSize(maxHeight, heightMeasureSpec));
  }

  private void drawPict(Canvas canvas, int x, int y, int w, int h, float sx,
      float sy) {
    canvas.save();
    canvas.translate(x, y);
    canvas.clipRect(0, 0, w, h);
    canvas.scale(0.5f, 0.5f);
    canvas.scale(sx, sy, w, h);
    canvas.drawPicture(mPicture);
    canvas.restore();
  }

  @Override
  protected void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(mPicture.beginRecording(getWidth(), getHeight()));
    mPicture.endRecording();

    int x = getWidth() / 2;
    int y = getHeight() / 2;

    if (false) {
      canvas.drawPicture(mPicture);
    } else {
      drawPict(canvas, 0, 0, x, y, 1, 1);
      drawPict(canvas, x, 0, x, y, -1, 1);
      drawPict(canvas, 0, y, x, y, 1, -1);
      drawPict(canvas, x, y, x, y, -1, -1);
    }
  }

  @Override
  public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
    location[0] = getLeft();
    location[1] = getTop();
    dirty.set(0, 0, getWidth(), getHeight());
    return getParent();
  }

  @Override
  protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int count = super.getChildCount();

    for (int i = 0; i < count; i++) {
      final View child = getChildAt(i);
      if (child.getVisibility() != GONE) {
        final int childLeft = getPaddingLeft();
        final int childTop = getPaddingTop();
        child.layout(childLeft, childTop,
            childLeft + child.getMeasuredWidth(),
            childTop + child.getMeasuredHeight());

      }
    }
  }
}