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Vertical and horizontal scrolling in Listview

I am trying to create a shared list in a horizontal listview . Horizontal scrolling is OK, but vertical scrolling does not work. I tried to use this solution, but nothing happened. What should I do?

HorizontalListviewDemo.java

package com.devsmart.android.ui; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import android.app.Activity; import android.os.Bundle; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.view.View.OnTouchListener; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.LinearLayout.LayoutParams; import android.widget.ListView; import android.widget.SimpleAdapter; import android.widget.TextView; import com.devsmart.android.ui.HorizontialListView; import com.example.horlistview.R; public class HorizontalListViewDemo extends Activity { private final static String ITEM = "item"; private static int COLUMN_COUNT = 20; private static int ROW_COUNT = 50; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.listviewdemo); HorizontialListView listview = (HorizontialListView) findViewById(R.id.listview); listview.setAdapter(mAdapter); } static class VerticalViewHolder { protected TextView textview; } public void setColumnCount(int n) { COLUMN_COUNT = n; } public void setRowCount(int n) { ROW_COUNT = n; } private BaseAdapter mAdapter = new BaseAdapter() { public int getCount() { return COLUMN_COUNT; } public Object getItem(int position) { return null; } public long getItemId(int position) { return 0; } public View getView(int position, View convertView, ViewGroup parent) { final List<Map<String, String>> l = createList(); convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.viewitem, null); final ListView listview = (ListView) convertView.findViewById(R.id.viewitem_listview); if (position==0) { listview.setLayoutParams(new LayoutParams(parent.getWidth()-50, LayoutParams.WRAP_CONTENT)); listview.setAdapter(new SimpleAdapter( getApplicationContext(), l, R.layout.viewitemitem, new String[] {ITEM}, new int[] {R.id.textView}) { @Override public View getView(int position, View convertView, ViewGroup parent) { VerticalViewHolder verticalViewHolder = null; if (convertView==null) { convertView = super.getView(position, convertView, parent); verticalViewHolder = new VerticalViewHolder(); verticalViewHolder.textview = (TextView) convertView.findViewById(R.id.textView); LayoutParams lp = (LayoutParams) verticalViewHolder.textview.getLayoutParams(); if (position==0) lp.setMargins(1, 2, 1, 0); else lp.setMargins(1, 0, 1, 0); convertView.setTag(verticalViewHolder); convertView.setTag(R.id.textView, verticalViewHolder.textview); } else { verticalViewHolder = (VerticalViewHolder) convertView.getTag(); } verticalViewHolder.textview.setText(l.get(position).get(ITEM)); return convertView; } }); } else { if (COLUMN_COUNT>=5) listview.setLayoutParams(new LayoutParams(parent.getWidth()/5, LayoutParams.WRAP_CONTENT)); else listview.setLayoutParams(new LayoutParams(parent.getWidth()/COLUMN_COUNT, LayoutParams.WRAP_CONTENT)); listview.setAdapter(new SimpleAdapter( getApplicationContext(), l, R.layout.viewitemitem, new String[] {ITEM}, new int[] {R.id.textView}) { @Override public View getView(int position, View convertView, ViewGroup parent) { View retval = super.getView(position, convertView, parent); TextView textview = (TextView) retval.findViewById(R.id.textView); LayoutParams lp = (LayoutParams) textview.getLayoutParams(); if (position==0) lp.setMargins(0, 2, 1, 0); else if (position==ROW_COUNT-1) lp.setMargins(0, 0, 1, 1); else lp.setMargins(0, 0, 1, 0); return retval; } }); } convertView.setOnTouchListener(new OnTouchListener() { public boolean onTouch(View v, MotionEvent event) { listview.setSmoothScrollbarEnabled(true); listview.dispatchTouchEvent(event); return false; } }); return convertView; } private List<Map<String, String>> createList() { List<Map<String, String>> values = new ArrayList<Map<String, String>>(); Map<String, String> v = new HashMap<String, String>(); for (int j = 0; j < ROW_COUNT; j++) { v = new HashMap<String, String>(); v.put(ITEM, ""+j); values.add(v); } return values; } }; }

HorizontalListView.java

 /* * HorizontalListView.java v1.5 * * * The MIT License * Copyright (c) 2011 Paul Soucy ( paul@dev-smart.com ) * * 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. * */ package com.devsmart.android.ui; import java.util.LinkedList; import java.util.Queue; import android.content.Context; import android.database.DataSetObserver; import android.graphics.Rect; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.GestureDetector.OnGestureListener; import android.view.MotionEvent; import android.view.View; import android.widget.AdapterView; import android.widget.ListAdapter; import android.widget.Scroller; public class HorizontialListView 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 boolean mDataChanged = false; public HorizontialListView(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; } private DataSetObserver mDataObserver = new DataSetObserver() { @Override public void onChanged() { synchronized(HorizontialListView.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(){ 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(); } 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(HorizontialListView.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 HorizontialListView.this.onDown(e); } @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { return HorizontialListView.this.onFling(e1, e2, velocityX, velocityY); } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { synchronized(HorizontialListView.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(HorizontialListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i )); } if(mOnItemSelected != null){ mOnItemSelected.onItemSelected(HorizontialListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i )); } break; } } return true; } }; }

listviewdemo.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:orientation="vertical" > <com.devsmart.android.ui.HorizontialListView android:id="@+id/listview" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="#fff"/> </LinearLayout>

viewitem.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/viewitem_linearlayout" android:layout_width="wrap_content" android:layout_height="match_parent" > <ListView android:id="@+id/viewitem_listview" android:layout_width="wrap_content" android:layout_height="wrap_content" > </ListView> </LinearLayout>

viewitemitem.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/viewitemitem" android:layout_width="match_parent" android:layout_height="match_parent" android:background="#fff" > <TextView android:id="@+id/textView" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="#000" android:paddingLeft="3dp" android:text="@string/hello_world" /> </LinearLayout>
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Try my code below, which is configured by HorizontalScrollingPage , which provides functions for scrolling views vertically and horizontally containing a list.

HorizontalPagerWithPageControl.class

  package com.wli.horizontalpager.withpagecontrol; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Color; import android.graphics.drawable.Drawable; import android.graphics.drawable.ShapeDrawable; import android.graphics.drawable.shapes.OvalShape; import android.graphics.drawable.shapes.Shape; import android.util.AttributeSet; import android.util.DisplayMetrics; import android.view.Display; import android.view.Gravity; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.Scroller; public final class HorizontalPagerWithPageControl extends ViewGroup { /* * How long to animate between screens when programmatically setting with * setCurrentScreen using the animate parameter */ private static final int ANIMATION_SCREEN_SET_DURATION_MILLIS = 500; // What fraction (1/x) of the screen the user must swipe to indicate a page // change private static final int FRACTION_OF_SCREEN_WIDTH_FOR_SWIPE = 4; private static final int INVALID_SCREEN = -1; /* * Velocity of a swipe (in density-independent pixels per second) to force a * swipe to the next/previous screen. Adjusted into * mDensityAdjustedSnapVelocity on init. */ private static final int SNAP_VELOCITY_DIP_PER_SECOND = 600; // Argument to getVelocity for units to give pixels per second (1 = pixels // per millisecond). private static final int VELOCITY_UNIT_PIXELS_PER_SECOND = 1000; private static final int TOUCH_STATE_REST = 0; private static final int TOUCH_STATE_HORIZONTAL_SCROLLING = 1; private static final int TOUCH_STATE_VERTICAL_SCROLLING = -1; private int m_currentScreen; private int m_densityAdjustedSnapVelocity; private boolean m_firstLayout = true; private float m_lastMotionX; private float m_lastMotionY; private OnScreenSwitchListener m_onScreenSwitchListener; private int m_maximumVelocity; private int m_nextScreen = INVALID_SCREEN; private Scroller m_scroller; private int m_touchSlop; private int m_touchState = TOUCH_STATE_REST; private VelocityTracker m_velocityTracker; private int m_lastSeenLayoutWidth = -1; // Active and inactive draw private Drawable m_activeDrawable; private Drawable m_inactiveDrawable; // The size for the drawables private float m_indicatorSize; // The screen scale to get px to dip private static float SCALE; /** * Simple constructor to use when creating a view from code. * * @param p_context * The Context the view is running in, through which it can * access the current theme, resources, etc. */ public HorizontalPagerWithPageControl(final Context p_context) { super(p_context); init(); } /** * Constructor that is called when inflating a view from XML. This is called * when a view is being constructed from an XML file, supplying attributes * that were specified in the XML file. This version uses a default style of * 0, so the only attribute values applied are those in the Context Theme * and the given AttributeSet. * * <p> * The method onFinishInflate() will be called after all children have been * added. * * @param p_context * The Context the view is running in, through which it can * access the current theme, resources, etc. * @param p_attrs * The attributes of the XML tag that is inflating the view. * @see #View(Context, AttributeSet, int) */ public HorizontalPagerWithPageControl(final Context p_context, final AttributeSet p_attrs) { super(p_context, p_attrs); init(); } /** * Sets up the scroller and touch/fling sensitivity parameters for the * pager. */ private void init() { m_scroller = new Scroller(getContext()); // get the screen density SCALE = getResources().getDisplayMetrics().density; // set the indicator size resolution independent m_indicatorSize = (7 * SCALE); // Calculate the density-dependent snap velocity in pixels DisplayMetrics m_displayMetrics = new DisplayMetrics(); ((WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE)) .getDefaultDisplay().getMetrics(m_displayMetrics); m_densityAdjustedSnapVelocity = (int) (m_displayMetrics.density * SNAP_VELOCITY_DIP_PER_SECOND); final ViewConfiguration m_configuration = ViewConfiguration .get(getContext()); m_touchSlop = m_configuration.getScaledTouchSlop(); m_maximumVelocity = m_configuration.getScaledMaximumFlingVelocity(); // draw the shapes makeShapes(); } @Override protected void onMeasure(final int p_widthMeasureSpec, final int p_heightMeasureSpec) { super.onMeasure(p_widthMeasureSpec, p_heightMeasureSpec); final int m_width = MeasureSpec.getSize(p_widthMeasureSpec); final int m_widthMode = MeasureSpec.getMode(p_widthMeasureSpec); if (m_widthMode != MeasureSpec.EXACTLY) { throw new IllegalStateException( "ViewSwitcher can only be used in EXACTLY mode."); } final int m_heightMode = MeasureSpec.getMode(p_heightMeasureSpec); if (m_heightMode != MeasureSpec.EXACTLY) { throw new IllegalStateException( "ViewSwitcher can only be used in EXACTLY mode."); } // The children are given the same width and height as the workspace final int m_count = getChildCount(); for (int m_i = 0; m_i < m_count; m_i++) { getChildAt(m_i).measure(p_widthMeasureSpec, p_heightMeasureSpec); } if (m_firstLayout) { scrollTo(m_currentScreen * m_width, 0); m_firstLayout = false; } else if (m_width != m_lastSeenLayoutWidth) { // Width has changed /* * Recalculate the width and scroll to the right position to be sure * we're in the right place in the event that we had a rotation that * didn't result in an activity restart (code by aveyD). Without * this you can end up between two pages after a rotation. */ Display m_display = ((WindowManager) getContext().getSystemService( Context.WINDOW_SERVICE)).getDefaultDisplay(); int m_displayWidth = m_display.getWidth(); m_nextScreen = Math.max(0, Math.min(getCurrentScreen(), getChildCount() - 1)); final int m_newX = m_nextScreen * m_displayWidth; final int m_delta = m_newX - getScrollX(); m_scroller.startScroll(getScrollX(), 0, m_delta, 0, 0); } m_lastSeenLayoutWidth = m_width; } @Override protected void onLayout(final boolean p_changed, final int p_l, final int p_t, final int p_r, final int p_b) { int m_childLeft = 0; final int m_count = getChildCount(); for (int m_i = 0; m_i < m_count; m_i++) { final View m_child = getChildAt(m_i); if (m_child.getVisibility() != View.GONE) { final int m_childWidth = m_child.getMeasuredWidth(); m_child.layout(m_childLeft, 0, m_childLeft + m_childWidth, m_child.getMeasuredHeight()); m_childLeft += m_childWidth; } } } @Override public boolean onInterceptTouchEvent(final MotionEvent p_ev) { /* * By Yoni Samlan: Modified onInterceptTouchEvent based on standard * ScrollView onIntercept. The logic is designed to support a nested * vertically scrolling view inside this one; once a scroll registers * for X-wise scrolling, handle it in this view and don't let the * children, but once a scroll registers for y-wise scrolling, let the * children handle it exclusively. */ final int m_action = p_ev.getAction(); boolean m_intercept = false; switch (m_action) { case MotionEvent.ACTION_MOVE: /* * If we're in a horizontal scroll event, take it (intercept further * events). But if we're mid-vertical-scroll, don't even try; let * the children deal with it. If we haven't found a scroll event * yet, check for one. */ if (m_touchState == TOUCH_STATE_HORIZONTAL_SCROLLING) { /* * We've already started a horizontal scroll; set intercept to * true so we can take the remainder of all touch events in * onTouchEvent. */ m_intercept = true; } else if (m_touchState == TOUCH_STATE_VERTICAL_SCROLLING) { // Let children handle the events for the duration of the scroll // event. m_intercept = false; } else { // We haven't picked up a scroll event yet; check for one. /* * If we detected a horizontal scroll event, start stealing * touch events (mark as scrolling). Otherwise, see if we had a * vertical scroll event -- if so, let the children handle it * and don't look to intercept again until the motion is done. */ final float m_x = p_ev.getX(); final int m_xDiff = (int) Math.abs(m_x - m_lastMotionX); boolean m_xMoved = m_xDiff > m_touchSlop; if (m_xMoved) { // Scroll if the user moved far enough along the X axis m_touchState = TOUCH_STATE_HORIZONTAL_SCROLLING; m_lastMotionX = m_x; } final float m_y = p_ev.getY(); final int m_yDiff = (int) Math.abs(m_y - m_lastMotionY); boolean m_yMoved = m_yDiff > m_touchSlop; if (m_yMoved) { m_touchState = TOUCH_STATE_VERTICAL_SCROLLING; } } break; case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP: // Release the drag. m_touchState = TOUCH_STATE_REST; break; case MotionEvent.ACTION_DOWN: /* * No motion yet, but register the coordinates so we can check for * intercept at the next MOVE event. */ m_lastMotionY = p_ev.getY(); m_lastMotionX = p_ev.getX(); break; default: break; } return m_intercept; } @Override public boolean onTouchEvent(final MotionEvent p_ev) { if (m_velocityTracker == null) { m_velocityTracker = VelocityTracker.obtain(); } m_velocityTracker.addMovement(p_ev); final int m_action = p_ev.getAction(); final float m_x = p_ev.getX(); switch (m_action) { case MotionEvent.ACTION_DOWN: /* * If being flinged and user touches, stop the fling. isFinished * will be false if being flinged. */ if (!m_scroller.isFinished()) { m_scroller.abortAnimation(); } // Remember where the motion event started m_lastMotionX = m_x; if (m_scroller.isFinished()) { m_touchState = TOUCH_STATE_REST; } else { m_touchState = TOUCH_STATE_HORIZONTAL_SCROLLING; } break; case MotionEvent.ACTION_MOVE: final int m_xDiff = (int) Math.abs(m_x - m_lastMotionX); boolean m_xMoved = m_xDiff > m_touchSlop; if (m_xMoved) { // Scroll if the user moved far enough along the X axis m_touchState = TOUCH_STATE_HORIZONTAL_SCROLLING; } if (m_touchState == TOUCH_STATE_HORIZONTAL_SCROLLING) { // Scroll to follow the motion event final int m_deltaX = (int) (m_lastMotionX - m_x); m_lastMotionX = m_x; final int m_scrollX = getScrollX(); if (m_deltaX < 0) { if (m_scrollX > 0) { scrollBy(Math.max(-m_scrollX, m_deltaX), 0); } } else if (m_deltaX > 0) { final int m_availableToScroll = getChildAt( getChildCount() - 1).getRight() - m_scrollX - getWidth(); if (m_availableToScroll > 0) { scrollBy(Math.min(m_availableToScroll, m_deltaX), 0); } } } break; case MotionEvent.ACTION_UP: if (m_touchState == TOUCH_STATE_HORIZONTAL_SCROLLING) { final VelocityTracker m_velocityTrack = m_velocityTracker; m_velocityTrack.computeCurrentVelocity( VELOCITY_UNIT_PIXELS_PER_SECOND, m_maximumVelocity); int m_velocityX = (int) m_velocityTrack.getXVelocity(); if (m_velocityX > m_densityAdjustedSnapVelocity && m_currentScreen > 0) { // Fling hard enough to move left snapToScreen(m_currentScreen - 1); } else if (m_velocityX < -m_densityAdjustedSnapVelocity && m_currentScreen < getChildCount() - 1) { // Fling hard enough to move right snapToScreen(m_currentScreen + 1); } else { snapToDestination(); } if (m_velocityTracker != null) { m_velocityTracker.recycle(); m_velocityTracker = null; } } m_touchState = TOUCH_STATE_REST; break; case MotionEvent.ACTION_CANCEL: m_touchState = TOUCH_STATE_REST; break; default: break; } return true; } @Override public void computeScroll() { if (m_scroller.computeScrollOffset()) { scrollTo(m_scroller.getCurrX(), m_scroller.getCurrY()); postInvalidate(); } else if (m_nextScreen != INVALID_SCREEN) { m_currentScreen = Math.max(0, Math.min(m_nextScreen, getChildCount() - 1)); // Notify observer about screen change if (m_onScreenSwitchListener != null) { m_onScreenSwitchListener.onScreenSwitched(m_currentScreen); } m_nextScreen = INVALID_SCREEN; } } /** * Returns the index of the currently displayed screen. * * @return The index of the currently displayed screen. */ public int getCurrentScreen() { return m_currentScreen; } /** * Sets the current screen. * * @param p_currentScreen * The new screen. * @param p_animate * True to smoothly scroll to the screen, false to snap instantly */ public void setCurrentScreen(final int p_currentScreen, final boolean p_animate) { m_currentScreen = Math.max(0, Math.min(p_currentScreen, getChildCount() - 1)); if (p_animate) { snapToScreen(p_currentScreen, ANIMATION_SCREEN_SET_DURATION_MILLIS); } else { scrollTo(m_currentScreen * getWidth(), 0); } invalidate(); } /** * Sets the {@link OnScreenSwitchListener}. * * @param onScreenSwitchListener * The listener for switch events. */ public void setOnScreenSwitchListener( final OnScreenSwitchListener onScreenSwitchListener) { m_onScreenSwitchListener = onScreenSwitchListener; } /** * Snaps to the screen we think the user wants (the current screen for very * small movements; the next/prev screen for bigger movements). */ private void snapToDestination() { final int m_screenWidth = getWidth(); int m_scrollX = getScrollX(); int m_whichScreen = m_currentScreen; int m_deltaX = m_scrollX - (m_screenWidth * m_currentScreen); // Check if they want to go to the prev. screen if ((m_deltaX < 0) && m_currentScreen != 0 && ((m_screenWidth / FRACTION_OF_SCREEN_WIDTH_FOR_SWIPE) < -m_deltaX)) { m_whichScreen--; // Check if they want to go to the next screen } else if ((m_deltaX > 0) && (m_currentScreen + 1 != getChildCount()) && ((m_screenWidth / FRACTION_OF_SCREEN_WIDTH_FOR_SWIPE) < m_deltaX)) { m_whichScreen++; } snapToScreen(m_whichScreen); } /** * Snap to a specific screen, animating automatically for a duration * proportional to the distance left to scroll. * * @param p_whichScreen * Screen to snap to */ private void snapToScreen(final int p_whichScreen) { snapToScreen(p_whichScreen, -1); } /** * Snaps to a specific screen, animating for a specific amount of time to * get there. * * @param p_whichScreen * Screen to snap to * @param p_duration * -1 to automatically time it based on scroll distance; a * positive number to make the scroll take an exact duration. */ private void snapToScreen(final int p_whichScreen, final int p_duration) { /* * Modified by Yoni Samlan: Allow new snapping even during an ongoing * scroll animation. This is intended to make HorizontalPager work as * expected when used in conjunction with a RadioGroup used as "tabbed" * controls. Also, make the animation take a percentage of our normal * animation time, depending how far they've already scrolled. */ m_nextScreen = Math .max(0, Math.min(p_whichScreen, getChildCount() - 1)); final int m_newX = m_nextScreen * getWidth(); final int m_delta = m_newX - getScrollX(); if (p_duration < 0) { // Eg if they've scrolled 80% of the way, only animation for 20% // of the duration m_scroller .startScroll( getScrollX(), 0, m_delta, 0, (int) (Math.abs(m_delta) / (float) getWidth() * ANIMATION_SCREEN_SET_DURATION_MILLIS)); } else { m_scroller.startScroll(getScrollX(), 0, m_delta, 0, p_duration); } // sets the drawables when the user swipes setActiveInactiveDrawables(p_whichScreen); // redraw screen invalidate(); } /** * Allways called when the user swipes to another view. Gets the current * view an sets the active drawable / shape to the curretn view. (in the * page control) */ public void setActiveInactiveDrawables(int p_whichScreen) { // Getting the Linear Layout where the page control drawables are inside LinearLayout m_linLayout = (LinearLayout) ((ViewGroup) this.getParent()) .getChildAt(((LinearLayout) this.getParent()).getChildCount() - 1); // get every imageview and set the one of the current screen to active for (int m_i = 0; m_i < this.getChildCount(); m_i++) { ImageView m_imgView = (ImageView) m_linLayout.getChildAt(m_i); if (m_i == p_whichScreen) { m_imgView.setBackgroundDrawable(m_activeDrawable); } else { m_imgView.setBackgroundDrawable(m_inactiveDrawable); } } } /** * Listener for the event that the HorizontalPager switches to a new view. */ public static interface OnScreenSwitchListener { /** * Notifies listeners about the new screen. Runs after the animation * completed. * * @param screen * The new screen index. */ void onScreenSwitched(int screen); } /** * Builds the active and inactive shapes / drawables for the page control */ private void makeShapes() { m_activeDrawable = new ShapeDrawable(); m_inactiveDrawable = new ShapeDrawable(); m_activeDrawable.setBounds(0, 0, (int) m_indicatorSize, (int) m_indicatorSize); m_inactiveDrawable.setBounds(0, 0, (int) m_indicatorSize, (int) m_indicatorSize); int m_i[] = new int[2]; m_i[0] = android.R.attr.textColorSecondary; m_i[1] = android.R.attr.textColorSecondaryInverse; TypedArray a = getContext().getTheme().obtainStyledAttributes(m_i); Shape m_s1 = new OvalShape(); m_s1.resize(m_indicatorSize, m_indicatorSize); Shape m_s2 = new OvalShape(); m_s2.resize(m_indicatorSize, m_indicatorSize); ((ShapeDrawable) m_activeDrawable).getPaint().setColor( a.getColor(0, Color.DKGRAY)); ((ShapeDrawable) m_inactiveDrawable).getPaint().setColor( a.getColor(1, Color.LTGRAY)); ((ShapeDrawable) m_activeDrawable).setShape(m_s1); ((ShapeDrawable) m_inactiveDrawable).setShape(m_s2); } /** * Called by the Activity when all Views are added to the horizontal pager * to */ public void addPagerControl() { ViewGroup m_view = (ViewGroup) this.getParent(); m_view.addView(initPageControl()); } private LinearLayout initPageControl() { LinearLayout m_linearLayout = new LinearLayout(getContext()); LinearLayout.LayoutParams params = new LinearLayout.LayoutParams( LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.FILL_PARENT, 2f); m_linearLayout.setLayoutParams(params); m_linearLayout.setOrientation(LinearLayout.HORIZONTAL); m_linearLayout.setGravity(Gravity.CENTER_HORIZONTAL | Gravity.CENTER_VERTICAL); m_linearLayout.setBackgroundColor(Color.BLACK); return setPageCount(this.getChildCount(), m_linearLayout); } /** * Initializes the page control layout at be bottom of the news view. Draws * all page control shapes an set the active shape to the first view * * @param p_pageCount * the cout of the pages the user can swipe to * @param p_linearLayout2 * the page control linearlayout * @return the given layout filled with the page control shapes */ private LinearLayout setPageCount(int p_pageCount, LinearLayout p_linearLayout2) { for (int m_i = 0; m_i < p_pageCount; m_i++) { final ImageView m_imageView = new ImageView(getContext()); LinearLayout.LayoutParams m_params = new LinearLayout.LayoutParams( (int) m_indicatorSize, (int) m_indicatorSize); m_params.setMargins((int) m_indicatorSize / 2, (int) m_indicatorSize, (int) m_indicatorSize / 2, (int) m_indicatorSize); m_imageView.setLayoutParams(m_params); m_imageView.setBackgroundDrawable(m_inactiveDrawable); if (m_i == 0) { m_imageView.setBackgroundDrawable(m_activeDrawable); } p_linearLayout2.addView(m_imageView); } return p_linearLayout2; } }

HorizontalPagerWithPageControlActivity.class

 public class HorizontalPagerWithPageControlActivity extends Activity { private HorizontalPagerWithPageControl m_pager; // The data to show List<Map<String, String>> planetsList = new ArrayList<Map<String, String>>(); @Override public void onCreate(final Bundle p_savedInstanceState) { super.onCreate(p_savedInstanceState); setContentView(R.layout.horizontal_pager_with_page_control); m_pager = (HorizontalPagerWithPageControl) findViewById(R.id.hphorizontal_pager); /* * You can add more views to the horizontal pager here with * mPager.addChild() or in xml. When every view is in the horizontal * pager just call addPagerControl() on the horzizontal pager. */ initList(); // We get the ListView component from the layout ListView lv = (ListView) findViewById(R.id.listView); // This is a simple adapter that accepts as parameter // Context // Data list // The row layout that is used during the row creation // The keys used to retrieve the data // The View id used to show the data. The key number and the view id // must match SimpleAdapter simpleAdpt = new SimpleAdapter(this, planetsList, android.R.layout.simple_list_item_1, new String[] { "planet" }, new int[] { android.R.id.text1 }); lv.setAdapter(simpleAdpt); m_pager.addPagerControl(); } private void initList() { // We populate the planets planetsList.add(createPlanet("planet", "Mercury")); planetsList.add(createPlanet("planet", "Venus")); planetsList.add(createPlanet("planet", "Mars")); planetsList.add(createPlanet("planet", "Jupiter")); planetsList.add(createPlanet("planet", "Saturn")); planetsList.add(createPlanet("planet", "Uranus")); planetsList.add(createPlanet("planet", "Neptune")); } private HashMap<String, String> createPlanet(String key, String name) { HashMap<String, String> planet = new HashMap<String, String>(); planet.put(key, name); return planet; } }

horizontal_pager_with_page_control.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:orientation="vertical" > <com.wli.horizontalpager.withpagecontrol.HorizontalPagerWithPageControl android:id="@+id/hphorizontal_pager" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="0.1" > <TextView android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#f00" android:text="@string/lipsum" android:textColor="#000" android:textSize="24sp" android:textStyle="bold" /> <ScrollView android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#0f0" android:text="@string/lipsum" android:textColor="#000" android:textSize="24sp" android:textStyle="bold" /> </ScrollView> <ListView android:id="@+id/listView" android:layout_width="fill_parent" android:layout_height="fill_parent" /> </com.wli.horizontalpager.withpagecontrol.HorizontalPagerWithPageControl> </LinearLayout>

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