com.manning.androidhacks.hack003.view.CascadeLayout.java Source code

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Here is the source code for com.manning.androidhacks.hack003.view.CascadeLayout.java

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/*
50AH-code
=========
    
50 Android Hacks (http://manning.com/sessa/) book source code
    
    
Copyright (c) 2012 Manning
    
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.
    
    
*/

/*******************************************************************************
 * Copyright (c) 2012 Manning
 * See the file license.txt for copying permission.
 ******************************************************************************/
package com.manning.androidhacks.hack003.view;

import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;

import com.manning.androidhacks.hack003.R;

public class CascadeLayout extends ViewGroup {

    private int mHorizontalSpacing;
    private int mVerticalSpacing;

    public CascadeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CascadeLayout);

        try {
            mHorizontalSpacing = a.getDimensionPixelSize(R.styleable.CascadeLayout_horizontal_spacing,
                    getResources().getDimensionPixelSize(R.dimen.cascade_horizontal_spacing));

            mVerticalSpacing = a.getDimensionPixelSize(R.styleable.CascadeLayout_vertical_spacing,
                    getResources().getDimensionPixelSize(R.dimen.cascade_vertical_spacing));
        } finally {
            a.recycle();
        }

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int width = getPaddingLeft();
        int height = getPaddingTop();
        int verticalSpacing;

        final int count = getChildCount();
        for (int i = 0; i < count; i++) {
            verticalSpacing = mVerticalSpacing;

            View child = getChildAt(i);
            measureChild(child, widthMeasureSpec, heightMeasureSpec);

            LayoutParams lp = (LayoutParams) child.getLayoutParams();
            width = getPaddingLeft() + mHorizontalSpacing * i;

            lp.x = width;
            lp.y = height;

            if (lp.verticalSpacing >= 0) {
                verticalSpacing = lp.verticalSpacing;
            }

            width += child.getMeasuredWidth();
            height += verticalSpacing;
        }

        width += getPaddingRight();
        height += getChildAt(getChildCount() - 1).getMeasuredHeight() + getPaddingBottom();

        setMeasuredDimension(resolveSize(width, widthMeasureSpec), resolveSize(height, heightMeasureSpec));
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {

        final int count = getChildCount();
        for (int i = 0; i < count; i++) {
            View child = getChildAt(i);
            LayoutParams lp = (LayoutParams) child.getLayoutParams();

            child.layout(lp.x, lp.y, lp.x + child.getMeasuredWidth(), lp.y + child.getMeasuredHeight());
        }
    }

    @Override
    protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
        return p instanceof LayoutParams;
    }

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

    @Override
    public LayoutParams generateLayoutParams(AttributeSet attrs) {
        return new LayoutParams(getContext(), attrs);
    }

    @Override
    protected LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
        return new LayoutParams(p.width, p.height);
    }

    public static class LayoutParams extends ViewGroup.LayoutParams {
        int x;
        int y;
        public int verticalSpacing;

        public LayoutParams(Context context, AttributeSet attrs) {
            super(context, attrs);

            TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CascadeLayout_LayoutParams);
            try {
                verticalSpacing = a
                        .getDimensionPixelSize(R.styleable.CascadeLayout_LayoutParams_layout_vertical_spacing, -1);
            } finally {
                a.recycle();
            }
        }

        public LayoutParams(int w, int h) {
            super(w, h);
        }

    }
}