package com.emilsjolander.components.stickylistheaders;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
/**
*
* the view that wrapps a divider header and a normal list item. The listview sees this as 1 item
*
* @author Emil Sjölander
*/
public class WrapperView extends ViewGroup {
public View mItem;
public Drawable mDivider;
public int mDividerHeight;
public View mHeader;
public int mItemTop;
public WrapperView(Context c) {
super(c);
}
public void update(View item, View header, Drawable divider, int dividerHeight) {
//every wrapperview must have a list item
if (item == null) {
throw new NullPointerException("List view item must not be null.");
}
//only remove the current item if it is not the same as the new item. this can happen if wrapping a recycled view
if (this.mItem != item) {
removeView(this.mItem);
this.mItem = item;
final ViewParent parent = item.getParent();
if(parent != null && parent != this) {
if(parent instanceof ViewGroup) {
((ViewGroup) parent).removeView(item);
}
}
addView(item);
}
//same logik as above but for the header
if (this.mHeader != header) {
if (this.mHeader != null) {
removeView(this.mHeader);
}
this.mHeader = header;
if (header != null) {
addView(header);
}
}
if (this.mDivider != divider) {
this.mDivider = divider;
this.mDividerHeight = dividerHeight;
invalidate();
}
}
public boolean hasHeader() {
return mHeader != null;
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int measuredWidth = MeasureSpec.getSize(widthMeasureSpec);
int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(measuredWidth,
MeasureSpec.EXACTLY);
int measuredHeight = 0;
//measure header or divider. when there is a header visible it acts as the divider
if (mHeader != null) {
ViewGroup.LayoutParams params = mHeader.getLayoutParams();
if (params != null && params.height > 0) {
mHeader.measure(childWidthMeasureSpec,
MeasureSpec.makeMeasureSpec(params.height, MeasureSpec.EXACTLY));
} else {
mHeader.measure(childWidthMeasureSpec,
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
}
measuredHeight += mHeader.getMeasuredHeight();
} else if (mDivider != null) {
measuredHeight += mDividerHeight;
}
//measure item
ViewGroup.LayoutParams params = mItem.getLayoutParams();
if (params != null && params.height > 0) {
mItem.measure(childWidthMeasureSpec,
MeasureSpec.makeMeasureSpec(params.height, MeasureSpec.EXACTLY));
} else {
mItem.measure(childWidthMeasureSpec,
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
}
measuredHeight += mItem.getMeasuredHeight();
setMeasuredDimension(measuredWidth, measuredHeight);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
l = 0;
t = 0;
r = getWidth();
b = getHeight();
if (mHeader != null) {
int headerHeight = mHeader.getMeasuredHeight();
mHeader.layout(l, t, r, headerHeight);
mItemTop = headerHeight;
mItem.layout(l, headerHeight, r, b);
} else if (mDivider != null) {
mDivider.setBounds(l, t, r, mDividerHeight);
mItemTop = mDividerHeight;
mItem.layout(l, mDividerHeight, r, b);
} else {
mItemTop = t;
mItem.layout(l, t, r, b);
}
}
@Override
protected void dispatchDraw(Canvas canvas) {
super.dispatchDraw(canvas);
if (mHeader == null && mDivider != null) {
// Drawable.setBounds() does not seem to work pre-honeycomb. So have
// to do this instead
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB) {
canvas.clipRect(0, 0, getWidth(), mDividerHeight);
}
mDivider.draw(canvas);
}
}
}