继承LinearLayout实现根据屏幕宽度及内部子View个数自动排布GridView

public class VerticalSearchGridView extends LinearLayout implements View.OnClickListener {

private int mItemWidth;
private int mItemHeight;

public int mColumes;
public int mRows;
private final static int ITEM_MIN_HEIGH = DisplayManager.dipToPixel(75);
private final static int ITEM_WIDTH = DisplayManager.dipToPixel(75);
private final static int PADDING_LR= DisplayManager.dipToPixel(10);

private List<SearchEngineInfo> mSearchEngineInfos;
public VerticalSearchGridView(Context context) {

super(context);
}

public VerticalSearchGridView(Context context, AttributeSet attrs) {

super(context, attrs);
}

public VerticalSearchGridView(Context context, AttributeSet attrs, int defStyle) {

super(context, attrs, defStyle);
}

public void setData(List<SearchEngineInfo> searchEngineInfos){
mSearchEngineInfos = searchEngineInfos;
for (int i = 0; i < mSearchEngineInfos.size(); i++) {
SearchEngineGridItem item = new SearchEngineGridItem();
View childView = item.getView(i, this);
childView.setOnClickListener(this);
childView.setId(i);
addView(childView);
}
}
@Override
public void onClick(View v) {

int position = v.getId();
mOnitemClickListener.onItemClick(null, v, position, position);
}

private OnItemClickListener mOnitemClickListener;

public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.mOnitemClickListener=onItemClickListener;
}

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

int menuWidth = mItemWidth;
int menuHeight = mItemHeight;
for (int i = 0; i < mRows; i++) {
for (int j = 0; j < mColumes; j++) {
int index = i * mColumes + j;
if (index < getChildCount()) {
View child = getChildAt(index);
int x = j * menuWidth;
int y = i * menuHeight;
child.layout(x + PADDING_LR, y, x + menuWidth + PADDING_LR, y + menuHeight);
}
}
}
}

@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

if (MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.AT_MOST) {
widthMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.getSize(widthMeasureSpec),
MeasureSpec.EXACTLY);
}
if (MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.AT_MOST) {
heightMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.getSize(heightMeasureSpec),
MeasureSpec.EXACTLY);
}
int width = DisplayManager.screenWidthPixel(getContext()) - getResources().getDimensionPixelSize(R.dimen.search_engine_grid_margin_left)
- getResources().getDimensionPixelSize(R.dimen.search_engine_grid_margin_right);
int height = getDefaultSize(getSuggestedMinimumHeight(), heightMeasureSpec);
measureChildren(MeasureSpec.makeMeasureSpec(ITEM_WIDTH, MeasureSpec.EXACTLY),
MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
int maxHeight = ITEM_MIN_HEIGH;
int maxWidth = 0;
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
maxWidth = Math.max(maxWidth, child.getMeasuredWidth());
maxHeight = Math.max(maxHeight, child.getMeasuredHeight());
}
mItemWidth = maxWidth;
mItemHeight = maxHeight;

int totleCount = mSearchEngineInfos.size();
width = width - PADDING_LR * 2;

int oneLineCount = width / mItemWidth;
if(totleCount < oneLineCount){
mColumes = totleCount;
mRows = 1;
}else {// 一排放不下
mItemWidth = width / oneLineCount; //平均放
int adds = 0;
if (totleCount % oneLineCount != 0) {
adds = 1;
}
mColumes = oneLineCount;
mRows = totleCount / oneLineCount + adds; // 计算行数
}
setMeasuredDimension(mItemWidth * mColumes + PADDING_LR * 2, mItemHeight * mRows);
}

private final static int ITEM_PADDING_LR = DisplayManager.dipToPixel(5);

private class SearchEngineGridItem {

public View getView(int position, ViewGroup parent) {

View convertView = createView(parent);
bindView(position, convertView);
return convertView;
}

private View createView(ViewGroup parent) {

View v = LayoutInflater.from(getContext()).inflate(R.layout.search_engine_item, parent,
false);
return v;
}

private void bindView(int position, View view) {

final ImageView engineImg = (ImageView) view.findViewById(R.id.engine_item_img);
final TextView engineName = (TextView) view.findViewById(R.id.engine_item_text);

ThemeManager tm = ThemeManager.getInstance();
view.findViewById(R.id.engine_item).setBackgroundDrawable(
tm.getDrawable(R.drawable.search_engine_item_bg));
SearchEngineInfo searchEngineInfo = mSearchEngineInfos.get(position);
Drawable drawable = searchEngineInfo.getIconDrawable();
tm.applyDrawableAlpha(drawable);
engineImg.setBackgroundDrawable(drawable);
engineName.setTextColor(tm.getColor(R.color.search_engine_choose_item_textcolor));
engineName.setText(searchEngineInfo.getTitle());
engineName.setPadding(ITEM_PADDING_LR, 0, ITEM_PADDING_LR, 0);
}
}

}