src/com/android/browser/NavTabScroller.java - android_packages_apps_Gello - Gitiles

 /*
  * Copyright (C) 2011 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  * License for the specific language governing permissions and limitations under
  * the License.
  */

 package com.android.browser;

 import android.content.Context;
 import android.content.res.Configuration;
 import android.database.DataSetObserver;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 import android.widget.FrameLayout;
 import android.widget.LinearLayout;

 import com.android.browser.view.HorizontalScrollView;
 import com.android.browser.view.ScrollView;

 /**
  * custom view for displaying tabs in the nav screen
  */
 public class NavTabScroller extends FrameLayout {

     private LinearLayout mContentView;
     private BaseAdapter mAdapter;
     private SelectableSroller mScroller;
     private int mOrientation;

     public NavTabScroller(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);
         init(context);
     }

     public NavTabScroller(Context context, AttributeSet attrs) {
         super(context, attrs);
         init(context);
     }

     public NavTabScroller(Context context) {
         super(context);
         init(context);
     }

     private void init(Context ctx) {
         mOrientation = ctx.getResources().getConfiguration().orientation;
         mScroller = (mOrientation == Configuration.ORIENTATION_LANDSCAPE) ?
                 new HorizontalScroller(ctx) : new VerticalScroller(ctx);
         mContentView = mScroller.getContentView();
         View sview = (View) mScroller;
         sview.setLayoutParams(new FrameLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                 LayoutParams.MATCH_PARENT));
         addView(sview);
     }

     @Override
     protected void onMeasure(int wspec, int hspec) {
         super.onMeasure(wspec, hspec);
         calcPadding();
     }

     private void calcPadding() {
         if (mAdapter.getCount() > 0) {
             View v = mContentView.getChildAt(0);
             if (mOrientation == Configuration.ORIENTATION_PORTRAIT) {
                 int pad = (getMeasuredHeight() - v.getMeasuredHeight()) / 2;
                 mContentView.setPadding(0, pad, 0, pad);
             } else {
                 int pad = (getMeasuredWidth() - v.getMeasuredWidth()) / 2;
                 mContentView.setPadding(pad, 0, pad, 0);
             }
         }
     }

     protected void setAdapter(BaseAdapter adapter) {
         mAdapter = adapter;
         mAdapter.registerDataSetObserver(new DataSetObserver() {

             @Override
             public void onChanged() {
                 super.onChanged();
                 populateList();
             }

             @Override
             public void onInvalidated() {
                 super.onInvalidated();
             }
         });
         populateList();
     }

     protected void setSelection(int ix) {
         mScroller.setSelection(ix);
     }

     protected int getSelectionIndex() {
         return mScroller.getSelection();
     }

     protected Tab getSelectedItem() {
         return (Tab) mAdapter.getItem(mScroller.getSelection());
     }

     protected ViewGroup getContentView() {
         return mContentView;
     }

     private void populateList() {
         mContentView.removeAllViewsInLayout();
         for (int i = 0; i < mAdapter.getCount(); i++) {
             NavTabView v = (NavTabView) mAdapter.getView(i, null, mContentView);
             mContentView.addView(v);
         }
     }

     View getSelectedTab() {
         int selected = mScroller.getSelection();
         if ((selected >= 0) && (selected < mContentView.getChildCount())) {
             return mContentView.getChildAt(selected);
         } else {
             return null;
         }
     }

     static interface SelectableSroller {
         void setSelection(int index);
         int getSelection();
         LinearLayout getContentView();

     }

     static class VerticalScroller extends ScrollView implements SelectableSroller  {

         private LinearLayout mContentView;
         private int mSelected;
         private boolean mSnapScroll;

         public VerticalScroller(Context context, AttributeSet attrs, int defStyle) {
             super(context, attrs, defStyle);
             init(context);
         }

         public VerticalScroller(Context context, AttributeSet attrs) {
             super(context, attrs);
             init(context);
         }

         public VerticalScroller(Context context) {
             super(context);
             init(context);
         }

         private void init(Context ctx) {
             setHorizontalScrollBarEnabled(false);
             mContentView = new LinearLayout(ctx);
             mContentView.setOrientation(LinearLayout.VERTICAL);
             setVerticalScrollBarEnabled(false);
             setSmoothScrollingEnabled(true);
             mContentView.setLayoutParams(
                     new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
             addView(mContentView);

         }

         public LinearLayout getContentView() {
             return mContentView;
         }

         public void setSelection(int ix) {
             mSelected = ix;
         }

         public int getSelection() {
             return mSelected;
         }

         protected void onScrollChanged(int sl, int st, int ol, int ot) {
             int midy = getScrollY() + getHeight() / 2;
             int sel = -1;
             for (int i = 0; i < mContentView.getChildCount(); i++) {
                 NavTabView child = (NavTabView) mContentView.getChildAt(i);
                 int top = child.getTop();
                 int bottom = child.getBottom();
                 if (top <= midy && bottom >= midy) {
                     sel = i;
                 } else {
                     // check if on screen
                     if (top > getScrollY() + getHeight() || bottom < getScrollY()) {
                         if (!child.isPaused()) {
                             child.pause();
                         }
                     } else {
                         if (child.isPaused()) {
                             child.resume();
                         }
                     }
                 }
             }
             if (sel != -1) {
                 if (sel != mSelected) {
                     setSelection(sel);
                 }
             }
         }

         @Override
         public boolean onTouchEvent(MotionEvent evt) {
             // save drag state before super call
             boolean dragged = mIsBeingDragged;
             boolean result = super.onTouchEvent(evt);
             if (MotionEvent.ACTION_UP == evt.getActionMasked()) {
                 if (mScroller.isFinished() && dragged) {
                     snapToSelected();
                 }
             } else if (MotionEvent.ACTION_MOVE == evt.getActionMasked()) {
                 NavTabView ntv = (NavTabView) getSelectedView();
                 if (mIsBeingDragged && ntv.isHighlighted()) {
                     ntv.setHighlighted(false);
                 }
             }
             return result;
         }

         @Override
         public void computeScroll() {
             super.computeScroll();
             if (mScroller.isFinished() && !mIsBeingDragged) {
                 if (!mSnapScroll) {
                     snapToSelected();
                 } else {
                     // reset snap scrolling flag
                     mSnapScroll = false;
                     NavTabView ntv = (NavTabView) getSelectedView();
                     ntv.setHighlighted(true);
                 }
             }
         }

         private void snapToSelected() {
             View v = mContentView.getChildAt(mSelected);
             int top = (v.getTop() + v.getBottom()) / 2;
             top -= getHeight() / 2;
             if (top != getScrollY()) {
                 // snap to selected
                 mSnapScroll = true;
                 smoothScrollTo(0, top);
             } else {
                 NavTabView ntv = (NavTabView) getSelectedView();
                 ntv.setHighlighted(true);
             }
         }

         protected View getSelectedView() {
             return mContentView.getChildAt(mSelected);
         }

     }

     static class HorizontalScroller extends HorizontalScrollView implements SelectableSroller  {

         private LinearLayout mContentView;
         private int mSelected;
         private boolean mSnapScroll;

         public HorizontalScroller(Context context, AttributeSet attrs, int defStyle) {
             super(context, attrs, defStyle);
             init(context);
         }

         public HorizontalScroller(Context context, AttributeSet attrs) {
             super(context, attrs);
             init(context);
         }

         public HorizontalScroller(Context context) {
             super(context);
             init(context);
         }

         private void init(Context ctx) {
             setHorizontalScrollBarEnabled(false);
             mContentView = new LinearLayout(ctx);
             mContentView.setOrientation(LinearLayout.HORIZONTAL);
             setVerticalScrollBarEnabled(false);
             setSmoothScrollingEnabled(true);
             mContentView.setLayoutParams(
                     new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
             addView(mContentView);
         }

         public LinearLayout getContentView() {
             return mContentView;
         }

         public void setSelection(int ix) {
             mSelected = ix;
         }

         public int getSelection() {
             return mSelected;
         }

         protected void onScrollChanged(int sl, int st, int ol, int ot) {
             int midx = getScrollX() + getWidth() / 2;
             int sel = -1;
             for (int i = 0; i < mContentView.getChildCount(); i++) {
                 View child = mContentView.getChildAt(i);
                 if (child.getLeft() <= midx && child.getRight() >= midx) {
                     sel = i;
                     break;
                 }
             }
             if (sel != -1) {
                 if (sel != mSelected) {
                     setSelection(sel);
                 }
             }
         }

         @Override
         public boolean onTouchEvent(MotionEvent evt) {
             // save drag state before super call
             boolean dragged = mIsBeingDragged;
             boolean result = super.onTouchEvent(evt);
             if (MotionEvent.ACTION_UP == evt.getActionMasked()) {
                 if (mScroller.isFinished() && dragged) {
                     snapToSelected();
                 }
             } else if (MotionEvent.ACTION_MOVE == evt.getActionMasked()) {
                 NavTabView ntv = (NavTabView) getSelectedView();
                 if (mIsBeingDragged && ntv.isHighlighted()) {
                     ntv.setHighlighted(false);
                 }
             }
             return result;
         }

         @Override
         public void computeScroll() {
             super.computeScroll();
             if (mScroller.isFinished() && !mIsBeingDragged) {
                 if (!mSnapScroll) {
                     snapToSelected();
                 } else {
                     // reset snap scrolling flag
                     mSnapScroll = false;
                     NavTabView ntv = (NavTabView) getSelectedView();
                     ntv.setHighlighted(true);
                 }
             }
         }

         private void snapToSelected() {
             View v = mContentView.getChildAt(mSelected);
             int left = (v.getLeft() + v.getRight()) / 2;
             left -= getWidth() / 2;
             if (left != getScrollX()) {
                 // snap to selected
                 mSnapScroll = true;
                 smoothScrollTo(left, 0);
             } else {
                 NavTabView ntv = (NavTabView) getSelectedView();
                 ntv.setHighlighted(true);
             }
         }

         protected View getSelectedView() {
             return mContentView.getChildAt(mSelected);
         }

     }

 }
	/*
	* Copyright (C) 2011 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License"); you may not
	* use this file except in compliance with the License. You may obtain a copy of
	* the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
	* License for the specific language governing permissions and limitations under
	* the License.
	*/

	package com.android.browser;

	import android.content.Context;
	import android.content.res.Configuration;
	import android.database.DataSetObserver;
	import android.util.AttributeSet;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewGroup;
	import android.widget.BaseAdapter;
	import android.widget.FrameLayout;
	import android.widget.LinearLayout;

	import com.android.browser.view.HorizontalScrollView;
	import com.android.browser.view.ScrollView;

	/**
	* custom view for displaying tabs in the nav screen
	*/
	public class NavTabScroller extends FrameLayout {

	private LinearLayout mContentView;
	private BaseAdapter mAdapter;
	private SelectableSroller mScroller;
	private int mOrientation;

	public NavTabScroller(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);
	init(context);
	}

	public NavTabScroller(Context context, AttributeSet attrs) {
	super(context, attrs);
	init(context);
	}

	public NavTabScroller(Context context) {
	super(context);
	init(context);
	}

	private void init(Context ctx) {
	mOrientation = ctx.getResources().getConfiguration().orientation;
	mScroller = (mOrientation == Configuration.ORIENTATION_LANDSCAPE) ?
	new HorizontalScroller(ctx) : new VerticalScroller(ctx);
	mContentView = mScroller.getContentView();
	View sview = (View) mScroller;
	sview.setLayoutParams(new FrameLayout.LayoutParams(LayoutParams.MATCH_PARENT,
	LayoutParams.MATCH_PARENT));
	addView(sview);
	}

	@Override
	protected void onMeasure(int wspec, int hspec) {
	super.onMeasure(wspec, hspec);
	calcPadding();
	}

	private void calcPadding() {
	if (mAdapter.getCount() > 0) {
	View v = mContentView.getChildAt(0);
	if (mOrientation == Configuration.ORIENTATION_PORTRAIT) {
	int pad = (getMeasuredHeight() - v.getMeasuredHeight()) / 2;
	mContentView.setPadding(0, pad, 0, pad);
	} else {
	int pad = (getMeasuredWidth() - v.getMeasuredWidth()) / 2;
	mContentView.setPadding(pad, 0, pad, 0);
	}
	}
	}

	protected void setAdapter(BaseAdapter adapter) {
	mAdapter = adapter;
	mAdapter.registerDataSetObserver(new DataSetObserver() {

	@Override
	public void onChanged() {
	super.onChanged();
	populateList();
	}

	@Override
	public void onInvalidated() {
	super.onInvalidated();
	}
	});
	populateList();
	}

	protected void setSelection(int ix) {
	mScroller.setSelection(ix);
	}

	protected int getSelectionIndex() {
	return mScroller.getSelection();
	}

	protected Tab getSelectedItem() {
	return (Tab) mAdapter.getItem(mScroller.getSelection());
	}

	protected ViewGroup getContentView() {
	return mContentView;
	}

	private void populateList() {
	mContentView.removeAllViewsInLayout();
	for (int i = 0; i < mAdapter.getCount(); i++) {
	NavTabView v = (NavTabView) mAdapter.getView(i, null, mContentView);
	mContentView.addView(v);
	}
	}

	View getSelectedTab() {
	int selected = mScroller.getSelection();
	if ((selected >= 0) && (selected < mContentView.getChildCount())) {
	return mContentView.getChildAt(selected);
	} else {
	return null;
	}
	}

	static interface SelectableSroller {
	void setSelection(int index);
	int getSelection();
	LinearLayout getContentView();

	}

	static class VerticalScroller extends ScrollView implements SelectableSroller {

	private LinearLayout mContentView;
	private int mSelected;
	private boolean mSnapScroll;

	public VerticalScroller(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);
	init(context);
	}

	public VerticalScroller(Context context, AttributeSet attrs) {
	super(context, attrs);
	init(context);
	}

	public VerticalScroller(Context context) {
	super(context);
	init(context);
	}

	private void init(Context ctx) {
	setHorizontalScrollBarEnabled(false);
	mContentView = new LinearLayout(ctx);
	mContentView.setOrientation(LinearLayout.VERTICAL);
	setVerticalScrollBarEnabled(false);
	setSmoothScrollingEnabled(true);
	mContentView.setLayoutParams(
	new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
	addView(mContentView);

	}

	public LinearLayout getContentView() {
	return mContentView;
	}

	public void setSelection(int ix) {
	mSelected = ix;
	}

	public int getSelection() {
	return mSelected;
	}

	protected void onScrollChanged(int sl, int st, int ol, int ot) {
	int midy = getScrollY() + getHeight() / 2;
	int sel = -1;
	for (int i = 0; i < mContentView.getChildCount(); i++) {
	NavTabView child = (NavTabView) mContentView.getChildAt(i);
	int top = child.getTop();
	int bottom = child.getBottom();
	if (top <= midy && bottom >= midy) {
	sel = i;
	} else {
	// check if on screen
	if (top > getScrollY() + getHeight() \|\| bottom < getScrollY()) {
	if (!child.isPaused()) {
	child.pause();
	}
	} else {
	if (child.isPaused()) {
	child.resume();
	}
	}
	}
	}
	if (sel != -1) {
	if (sel != mSelected) {
	setSelection(sel);
	}
	}
	}

	@Override
	public boolean onTouchEvent(MotionEvent evt) {
	// save drag state before super call
	boolean dragged = mIsBeingDragged;
	boolean result = super.onTouchEvent(evt);
	if (MotionEvent.ACTION_UP == evt.getActionMasked()) {
	if (mScroller.isFinished() && dragged) {
	snapToSelected();
	}
	} else if (MotionEvent.ACTION_MOVE == evt.getActionMasked()) {
	NavTabView ntv = (NavTabView) getSelectedView();
	if (mIsBeingDragged && ntv.isHighlighted()) {
	ntv.setHighlighted(false);
	}
	}
	return result;
	}

	@Override
	public void computeScroll() {
	super.computeScroll();
	if (mScroller.isFinished() && !mIsBeingDragged) {
	if (!mSnapScroll) {
	snapToSelected();
	} else {
	// reset snap scrolling flag
	mSnapScroll = false;
	NavTabView ntv = (NavTabView) getSelectedView();
	ntv.setHighlighted(true);
	}
	}
	}

	private void snapToSelected() {
	View v = mContentView.getChildAt(mSelected);
	int top = (v.getTop() + v.getBottom()) / 2;
	top -= getHeight() / 2;
	if (top != getScrollY()) {
	// snap to selected
	mSnapScroll = true;
	smoothScrollTo(0, top);
	} else {
	NavTabView ntv = (NavTabView) getSelectedView();
	ntv.setHighlighted(true);
	}
	}

	protected View getSelectedView() {
	return mContentView.getChildAt(mSelected);
	}

	}

	static class HorizontalScroller extends HorizontalScrollView implements SelectableSroller {

	private LinearLayout mContentView;
	private int mSelected;
	private boolean mSnapScroll;

	public HorizontalScroller(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);
	init(context);
	}

	public HorizontalScroller(Context context, AttributeSet attrs) {
	super(context, attrs);
	init(context);
	}

	public HorizontalScroller(Context context) {
	super(context);
	init(context);
	}

	private void init(Context ctx) {
	setHorizontalScrollBarEnabled(false);
	mContentView = new LinearLayout(ctx);
	mContentView.setOrientation(LinearLayout.HORIZONTAL);
	setVerticalScrollBarEnabled(false);
	setSmoothScrollingEnabled(true);
	mContentView.setLayoutParams(
	new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
	addView(mContentView);
	}

	public LinearLayout getContentView() {
	return mContentView;
	}

	public void setSelection(int ix) {
	mSelected = ix;
	}

	public int getSelection() {
	return mSelected;
	}

	protected void onScrollChanged(int sl, int st, int ol, int ot) {
	int midx = getScrollX() + getWidth() / 2;
	int sel = -1;
	for (int i = 0; i < mContentView.getChildCount(); i++) {
	View child = mContentView.getChildAt(i);
	if (child.getLeft() <= midx && child.getRight() >= midx) {
	sel = i;
	break;
	}
	}
	if (sel != -1) {
	if (sel != mSelected) {
	setSelection(sel);
	}
	}
	}

	@Override
	public boolean onTouchEvent(MotionEvent evt) {
	// save drag state before super call
	boolean dragged = mIsBeingDragged;
	boolean result = super.onTouchEvent(evt);
	if (MotionEvent.ACTION_UP == evt.getActionMasked()) {
	if (mScroller.isFinished() && dragged) {
	snapToSelected();
	}
	} else if (MotionEvent.ACTION_MOVE == evt.getActionMasked()) {
	NavTabView ntv = (NavTabView) getSelectedView();
	if (mIsBeingDragged && ntv.isHighlighted()) {
	ntv.setHighlighted(false);
	}
	}
	return result;
	}

	@Override
	public void computeScroll() {
	super.computeScroll();
	if (mScroller.isFinished() && !mIsBeingDragged) {
	if (!mSnapScroll) {
	snapToSelected();
	} else {
	// reset snap scrolling flag
	mSnapScroll = false;
	NavTabView ntv = (NavTabView) getSelectedView();
	ntv.setHighlighted(true);
	}
	}
	}

	private void snapToSelected() {
	View v = mContentView.getChildAt(mSelected);
	int left = (v.getLeft() + v.getRight()) / 2;
	left -= getWidth() / 2;
	if (left != getScrollX()) {
	// snap to selected
	mSnapScroll = true;
	smoothScrollTo(left, 0);
	} else {
	NavTabView ntv = (NavTabView) getSelectedView();
	ntv.setHighlighted(true);
	}
	}

	protected View getSelectedView() {
	return mContentView.getChildAt(mSelected);
	}

	}

	}