问题
How to change background color when clicking on Horizontal Listview items in Android
So that users will know where they clicked.
Below is the code which I got from some internet site.
HorizontalListViewActivity.java
public class HorizontalListViewActivity extends Activity {
static BitmapFactory bf;
ArrayList<String> dataObjectsList = new ArrayList<String>();
ArrayList<Bitmap> myImageList = new ArrayList<Bitmap>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
HorizontalListView listview = (HorizontalListView) findViewById(R.id.listview);
listview.setAdapter(mAdapter);
dataObjectsList.add("Text #1");
dataObjectsList.add("Text #2");
dataObjectsList.add("Text #3");
dataObjectsList.add("Text #4");
myImageList.add(BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/Restaurent/app1.jpg"));
myImageList.add(BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/Restaurent/app2.jpg"));
myImageList.add(BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/Restaurent/app3.jpg"));
myImageList.add(BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/Restaurent/app4.jpg"));
listview.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
// TODO Auto-generated method stub
/*Toast.makeText(getApplicationContext(), "dataObjects[position]=="+dataObjectsList.get(arg2).toString(), 100).show();
Intent intent2 = new Intent(getApplicationContext(),Test.class);
intent2.putExtra("category", dataObjectsList.get(arg2).toString());
startActivity(intent2);*/
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
private static String[] dataObjects = new String[]{ "Delhi",
"Bangalore",
"Chennai",
"Pune" };
private static Bitmap[] myImage = new Bitmap[]{ BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/Restaurent/app1.jpg"),
BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/City/app2.jpg"),
BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/City/app3.jpg"),
BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getPath()+"/City/app4.jpg") };
private BaseAdapter mAdapter = new BaseAdapter() {
@Override
public int getCount() {
return dataObjects.length;
}
@Override
public Object getItem(int position) {
Toast.makeText(getApplicationContext(), "getItem 111111 position=="+position, 100).show();
return null;
}
@Override
public long getItemId(int position) {
Toast.makeText(getApplicationContext(), "getItemId position=="+position, 100).show();
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View retval = LayoutInflater.from(parent.getContext()).inflate(R.layout.viewitem, null);
TextView title = (TextView) retval.findViewById(R.id.title);
ImageView img=(ImageView) retval.findViewById(R.id.image);
img.setImageBitmap(myImageList.get(position));
title.setText(dataObjectsList.get(position).toString());
return retval;
}
};
}
HorizontalListView.java
public class HorizontalListView extends AdapterView<ListAdapter> {
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<View> mRemovedViewQueue = new LinkedList<View>();
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;
}
setEmptyView(getEmptyView());
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;
}
}
}
public synchronized void scrollTo(int x) {
mScroller.startScroll(mNextX, 0, x - mNextX, 0);
requestLayout();
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
boolean 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 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) {
getParent().requestDisallowInterceptTouchEvent(true);
synchronized(HorizontalListView.this){
mNextX += (int)distanceX;
}
requestLayout();
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
Rect viewRect = new Rect();
for(int i=0;i<getChildCount();i++){
View child = getChildAt(i);
int left = child.getLeft();
int right = child.getRight();
int top = child.getTop();
int bottom = child.getBottom();
viewRect.set(left, top, right, bottom);
if(viewRect.contains((int)e.getX(), (int)e.getY())){
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) {
Rect viewRect = new Rect();
int childCount = getChildCount();
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
int left = child.getLeft();
int right = child.getRight();
int top = child.getTop();
int bottom = child.getBottom();
viewRect.set(left, top, right, bottom);
if (viewRect.contains((int) e.getX(), (int) e.getY())) {
if (mOnItemLongClicked != null) {
mOnItemLongClicked.onItemLongClick(HorizontalListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId(mLeftViewIndex + 1 + i));
}
break;
}
}
}
};
}
viewitem.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#fff">
<ImageView
android:id="@+id/image"
android:layout_width="145dp"
android:layout_height="145dp"
android:layout_marginTop="5dp"
android:scaleType="centerCrop"
android:src="@drawable/ic_launcher"
/>
<TextView
android:id="@+id/title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="#000"
android:text="text"
android:gravity="center_horizontal"
/>
</LinearLayout>
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#fff"
android:orientation="vertical" >
<com.horilistview.HorizontalListView
android:id="@+id/listview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#ddd" />
</LinearLayout>
回答1:
For example in this implementation you can use listSelector
property in xml. Check out maybe yours also supports similar property or use the one I linked above.
回答2:
public View selectedRow;//declare this in class
Add this code in onitemSelectListner
if (selectedRow != null) {
selectedRow.setBackgroundResource(color.transparent);
}
selectedRow = view; //view is the onitemSelectListner View
view.setBackgroundResource(R.drawable.list_background);
this will work 3.0 and above version..
回答3:
add this onclick listener in getview method..
list.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
for(int j=0;j<20;j++)
{
test[j]=0;
}
for (int k = 0; k < mAdapter.getCount(); k++) {
View item = list.getChildAt(k);
if (item != null) {
test[k]=0;
item.setBackgroundColor(Color.WHITE);
}
view.setBackgroundColor(Color.BLUE);
test[i]=1;
}
}
test is a dummy array, use it out of onclicklistner to keep the selected even when view is changed.. like this..
if (test[position]==1) {
relativeLayout.setBackgroundColor(Color.BLUE);
}
if(test[position]==0)
relativeLayout.setBackgroundColor(Color.WHITE);
来源:https://stackoverflow.com/questions/22538993/how-to-change-background-color-when-click-on-horizontal-listview-items-in-androi