/* * Copyright (C) 2008 The Android Open Source Project * * 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. */package com.example.android.apis.graphics;import android.content.Context;import android.graphics.Canvas;import android.graphics.Picture;import android.graphics.Rect;import android.graphics.drawable.Drawable;import android.util.AttributeSet;import android.view.View;import android.view.ViewGroup;import android.view.ViewParent;public 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.FILL_PARENT, LayoutParams.FILL_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());            }        }    }}