项目前期写了个搜索历史展示,后来不用了,保存一下。
使用GreenDao保存历史到本地数据库
//初始化greendao
DaoMaster.DevOpenHelper devOpenHelper = new DaoMaster.DevOpenHelper(VideoApplication.getContext(), "history-db", null);
DaoMaster daoMaster = new DaoMaster(devOpenHelper.getWritableDatabase());
daoSession = daoMaster.newSession();
mGreenDao = daoSession.getHistoryBeanDao();
通过hashset保存数据,不会出现重复数据
/**
* 数据库查询
*/
public void selectSqLite() {
set.clear();
List beanList = mGreenDao.queryBuilder().list();
if (beanList.size() != 0) {
for (HistoryBean li : beanList) {
set.add(li.getTitle());
}
}
if (index != 0) {
mHotList.removeViews(0, index);
index = 0;
isFrist = false;
mHotList.requestLayout();
}
//添加布局
Iterator iterator = set.iterator();
while (iterator.hasNext()) {
View view = LayoutInflater.from(this).inflate(R.layout.searcher_history_list, mHotList, false);
TextView item_tv = view.findViewById(R.id.history_item_tv);
item_tv.setText(iterator.next());
mHotList.addView(view, 0);
index++;
mHotList.requestLayout();
}
}
/**
* 数据库删除
*/
public void deleteSqLite() {
daoSession.clear();
mGreenDao.deleteAll();
if (index != 0) {
mHotList.removeViews(0, index);
index = 0;
isFrist = false;
mHotList.requestLayout();
}
}
/**
* 数据库插入
*/
public void insertSqLite(String title) {
if (title.equals("")) {
return;
}
//先查询是否有重复数据
List beanList = mGreenDao.queryBuilder().list();
for (HistoryBean li : beanList) {
if (title.equals(li.getTitle())) {
//没有重复的再插入
isFrist = true;
} else {
isFrist = false;
}
}
if (isFrist) {
return;
}
HistoryBean hisBean = new HistoryBean(null, title);
mGreenDao.insert(hisBean);
}
数据暂时使用的死数据
public void setData() {
for (int i = 0; i < 10; i++) {
if (i % 2 == 0) {
dateList.add("电饭锅");
} else {
dateList.add("锅");
}
}
adapter = new HorizontalListViewAdapter(this);
mHorizontalListView.setAdapter(adapter);
adapter.setData(dateList);
}
mHorizontalListView是一个横向的列表,支持滑动,用的网上一位博主的轮子,具体谁给忘了,抱歉。
public class HorizontalListView extends AdapterView {
public boolean mAlwaysOverrideTouch = true;
protected ListAdapter mAdapter;
private int mLeftViewIndex = -1;
private int mRightViewIndex = 0;
protected int mCurrentX;
protected int mNextX;
private int mMaxX = Integer.MAX_VALUE;
private int mDisplayOffset = 0;
protected Scroller mScroller;
private GestureDetector mGesture;
private Queue mRemovedViewQueue = new LinkedList();
private OnItemSelectedListener mOnItemSelected;
private OnItemClickListener mOnItemClicked;
private OnItemLongClickListener mOnItemLongClicked;
private boolean mDataChanged = false;
public HorizontalListView(Context context, AttributeSet attrs) {
super(context, attrs);
initView();
}
private synchronized void initView() {
mLeftViewIndex = -1;
mRightViewIndex = 0;
mDisplayOffset = 0;
mCurrentX = 0;
mNextX = 0;
mMaxX = Integer.MAX_VALUE;
mScroller = new Scroller(getContext());
mGesture = new GestureDetector(getContext(), mOnGesture);
}
@Override
public void setOnItemSelectedListener(
AdapterView.OnItemSelectedListener listener) {
mOnItemSelected = listener;
}
@Override
public void setOnItemClickListener(AdapterView.OnItemClickListener listener) {
mOnItemClicked = listener;
}
@Override
public void setOnItemLongClickListener(
AdapterView.OnItemLongClickListener listener) {
mOnItemLongClicked = listener;
}
private DataSetObserver mDataObserver = new DataSetObserver() {
@Override
public void onChanged() {
synchronized (HorizontalListView.this) {
mDataChanged = true;
}
invalidate();
requestLayout();
}
@Override
public void onInvalidated() {
reset();
invalidate();
requestLayout();
}
};
@Override
public ListAdapter getAdapter() {
return mAdapter;
}
@Override
public View getSelectedView() {
// TODO: implement
return null;
}
@Override
public void setAdapter(ListAdapter adapter) {
if (mAdapter != null) {
mAdapter.unregisterDataSetObserver(mDataObserver);
}
mAdapter = adapter;
mAdapter.registerDataSetObserver(mDataObserver);
reset();
}
private synchronized void reset() {
initView();
removeAllViewsInLayout();
requestLayout();
}
@Override
public void setSelection(int position) {
// TODO: implement
}
private void addAndMeasureChild(final View child, int viewPos) {
LayoutParams params = child.getLayoutParams();
if (params == null) {
params = new LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT);
}
addViewInLayout(child, viewPos, params, true);
child.measure(
MeasureSpec.makeMeasureSpec(getWidth(), MeasureSpec.AT_MOST),
MeasureSpec.makeMeasureSpec(getHeight(), MeasureSpec.AT_MOST));
}
@Override
protected synchronized void onLayout(boolean changed, int left, int top,
int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if (mAdapter == null) {
return;
}
if (mDataChanged) {
int oldCurrentX = mCurrentX;
initView();
removeAllViewsInLayout();
mNextX = oldCurrentX;
mDataChanged = false;
}
if (mScroller.computeScrollOffset()) {
int scrollx = mScroller.getCurrX();
mNextX = scrollx;
}
if (mNextX <= 0) {
mNextX = 0;
mScroller.forceFinished(true);
}
if (mNextX >= mMaxX) {
mNextX = mMaxX;
mScroller.forceFinished(true);
}
int dx = mCurrentX - mNextX;
removeNonVisibleItems(dx);
fillList(dx);
positionItems(dx);
mCurrentX = mNextX;
if (!mScroller.isFinished()) {
post(new Runnable() {
@Override
public void run() {
requestLayout();
}
});
}
}
private void fillList(final int dx) {
int edge = 0;
View child = getChildAt(getChildCount() - 1);
if (child != null) {
edge = child.getRight();
}
fillListRight(edge, dx);
edge = 0;
child = getChildAt(0);
if (child != null) {
edge = child.getLeft();
}
fillListLeft(edge, dx);
}
private void fillListRight(int rightEdge, final int dx) {
while (rightEdge + dx < getWidth()
&& mRightViewIndex < mAdapter.getCount()) {
View child = mAdapter.getView(mRightViewIndex,
mRemovedViewQueue.poll(), this);
addAndMeasureChild(child, -1);
rightEdge += child.getMeasuredWidth();
if (mRightViewIndex == mAdapter.getCount() - 1) {
mMaxX = mCurrentX + rightEdge - getWidth();
}
if (mMaxX < 0) {
mMaxX = 0;
}
mRightViewIndex++;
}
}
private void fillListLeft(int leftEdge, final int dx) {
while (leftEdge + dx > 0 && mLeftViewIndex >= 0) {
View child = mAdapter.getView(mLeftViewIndex,
mRemovedViewQueue.poll(), this);
addAndMeasureChild(child, 0);
leftEdge -= child.getMeasuredWidth();
mLeftViewIndex--;
mDisplayOffset -= child.getMeasuredWidth();
}
}
private void removeNonVisibleItems(final int dx) {
View child = getChildAt(0);
while (child != null && child.getRight() + dx <= 0) {
mDisplayOffset += child.getMeasuredWidth();
mRemovedViewQueue.offer(child);
removeViewInLayout(child);
mLeftViewIndex++;
child = getChildAt(0);
}
child = getChildAt(getChildCount() - 1);
while (child != null && child.getLeft() + dx >= getWidth()) {
mRemovedViewQueue.offer(child);
removeViewInLayout(child);
mRightViewIndex--;
child = getChildAt(getChildCount() - 1);
}
}
private void positionItems(final int dx) {
if (getChildCount() > 0) {
mDisplayOffset += dx;
int left = mDisplayOffset;
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
int childWidth = child.getMeasuredWidth();
child.layout(left, 0, left + childWidth,
child.getMeasuredHeight());
left += childWidth + child.getPaddingRight();
}
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
boolean handled = super.dispatchTouchEvent(ev);
handled |= mGesture.onTouchEvent(ev);
return handled;
}
protected boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
synchronized (HorizontalListView.this) {
mScroller.fling(mNextX, 0, (int) -velocityX, 0, 0, mMaxX, 0, 0);
}
requestLayout();
return true;
}
protected boolean onDown(MotionEvent e) {
mScroller.forceFinished(true);
return true;
}
private GestureDetector.OnGestureListener mOnGesture = new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onDown(MotionEvent e) {
return HorizontalListView.this.onDown(e);
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
return HorizontalListView.this
.onFling(e1, e2, velocityX, velocityY);
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
synchronized (HorizontalListView.this) {
mNextX += (int) distanceX;
}
requestLayout();
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
if (isEventWithinView(e, child)) {
if (mOnItemClicked != null) {
mOnItemClicked.onItemClick(HorizontalListView.this,
child, mLeftViewIndex + 1 + i,
mAdapter.getItemId(mLeftViewIndex + 1 + i));
}
if (mOnItemSelected != null) {
mOnItemSelected.onItemSelected(HorizontalListView.this,
child, mLeftViewIndex + 1 + i,
mAdapter.getItemId(mLeftViewIndex + 1 + i));
}
break;
}
}
return true;
}
@Override
public void onLongPress(MotionEvent e) {
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
if (isEventWithinView(e, child)) {
if (mOnItemLongClicked != null) {
mOnItemLongClicked.onItemLongClick(
HorizontalListView.this, child, mLeftViewIndex
+ 1 + i,
mAdapter.getItemId(mLeftViewIndex + 1 + i));
}
break;
}
}
}
private boolean isEventWithinView(MotionEvent e, View child) {
Rect viewRect = new Rect();
int[] childPosition = new int[2];
child.getLocationOnScreen(childPosition);
int left = childPosition[0];
int right = left + child.getWidth();
int top = childPosition[1];
int bottom = top + child.getHeight();
viewRect.set(left, top, right, bottom);
return viewRect.contains((int) e.getRawX(), (int) e.getRawY());
}
};
}
动态添加控件的ViewGroup
public class MyViewGroup extends ViewGroup {
public MyViewGroup(Context context) {
super(context);
}
public MyViewGroup(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int maxWidth = MeasureSpec.getSize(widthMeasureSpec);
int childCount = getChildCount();
int x = 0;
int y = 0;
int row = 0;
for (int index = 0; index < childCount; index++) {
final View child = getChildAt(index);
if (child.getVisibility() != View.GONE) {
child.measure(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);
// 此处增加onlayout中的换行判断,用于计算所需的高度
int width = child.getMeasuredWidth();
int height = child.getMeasuredHeight();
x += width;
y = row * height + height;
if (x > maxWidth) {
x = width;
row++;
y = row * height + height;
}
}
}
// 设置容器所需的宽度和高度
setMeasuredDimension(maxWidth, y);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
final int childCount = getChildCount();
int maxWidth = r - l;
int x = 0;
int y = 0;
int row = 0;
for (int i = 0; i < childCount; i++) {
final View child = this.getChildAt(i);
if (child.getVisibility() != View.GONE) {
int width = child.getMeasuredWidth();
int height = child.getMeasuredHeight();
x += width;
y = row * height + height;
if (x > maxWidth) {
x = width;
row++;
y = row * height + height;
}
child.layout(x - width, y - height, x, y);
}
}
}
}