/*
* Copyright (C) 2010 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 com.android.browser.TabBar.TabView;
import android.animation.ObjectAnimator;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
/**
* custom view for displaying tabs in the tabbed title bar
*/
public class TabScrollView extends HorizontalScrollView {
private LinearLayout mContentView;
private int mSelected;
private int mAnimationDuration;
private int mTabOverlap;
/**
* @param context
* @param attrs
* @param defStyle
*/
public TabScrollView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
/**
* @param context
* @param attrs
*/
public TabScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
/**
* @param context
*/
public TabScrollView(Context context) {
super(context);
init(context);
}
private void init(Context ctx) {
mAnimationDuration = ctx.getResources().getInteger(
R.integer.tab_animation_duration);
mTabOverlap = (int) ctx.getResources().getDimension(R.dimen.tab_overlap);
setHorizontalScrollBarEnabled(false);
setOverScrollMode(OVER_SCROLL_NEVER);
mContentView = new TabLayout(ctx);
mContentView.setOrientation(LinearLayout.HORIZONTAL);
mContentView.setLayoutParams(
new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
mContentView.setPadding(
(int) ctx.getResources().getDimension(R.dimen.tab_first_padding_left),
0, 0, 0);
addView(mContentView);
mSelected = -1;
// prevent ProGuard from removing the property methods
setScroll(getScroll());
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
ensureChildVisible(getSelectedTab());
}
// in case of a configuration change, adjust tab width
protected void updateLayout() {
final int count = mContentView.getChildCount();
for (int i = 0; i < count; i++) {
final TabView tv = (TabView) mContentView.getChildAt(i);
tv.updateLayoutParams();
}
ensureChildVisible(getSelectedTab());
}
void setSelectedTab(int position) {
View v = getSelectedTab();
if (v != null) {
v.setActivated(false);
}
mSelected = position;
v = getSelectedTab();
if (v != null) {
v.setActivated(true);
}
requestLayout();
}
int getChildIndex(View v) {
return mContentView.indexOfChild(v);
}
View getSelectedTab() {
if ((mSelected >= 0) && (mSelected < mContentView.getChildCount())) {
return mContentView.getChildAt(mSelected);
} else {
return null;
}
}
void clearTabs() {
mContentView.removeAllViews();
}
void addTab(View tab) {
mContentView.addView(tab);
tab.setActivated(false);
}
void removeTab(View tab) {
int ix = mContentView.indexOfChild(tab);
if (ix == mSelected) {
mSelected = -1;
} else if (ix < mSelected) {
mSelected--;
}
mContentView.removeView(tab);
}
private void ensureChildVisible(View child) {
if (child != null) {
int childl = child.getLeft();
int childr = childl + child.getWidth();
int viewl = getScrollX();
int viewr = viewl + getWidth();
if (childl < viewl) {
// need scrolling to left
animateScroll(childl);
} else if (childr > viewr) {
// need scrolling to right
animateScroll(childr - viewr + viewl);
}
}
}
// TODO: These animations are broken and don't work correctly, removing for now
// as animateOut is actually causing issues
// private void animateIn(View tab) {
// ObjectAnimator animator = ObjectAnimator.ofInt(tab, "TranslationX", 500, 0);
// animator.setDuration(mAnimationDuration);
// animator.start();
// }
//
// private void animateOut(final View tab) {
// ObjectAnimator animator = ObjectAnimator.ofInt(
// tab, "TranslationX", 0, getScrollX() - tab.getRight());
// animator.setDuration(mAnimationDuration);
// animator.addListener(new AnimatorListenerAdapter() {
// @Override
// public void onAnimationEnd(Animator animation) {
// mContentView.removeView(tab);
// }
// });
// animator.setInterpolator(new AccelerateInterpolator());
// animator.start();
// }
private void animateScroll(int newscroll) {
ObjectAnimator animator = ObjectAnimator.ofInt(this, "scroll", getScrollX(), newscroll);
animator.setDuration(mAnimationDuration);
animator.start();
}
/**
* required for animation
*/
public void setScroll(int newscroll) {
scrollTo(newscroll, getScrollY());
}
/**
* required for animation
*/
public int getScroll() {
return getScrollX();
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
super.onScrollChanged(l, t, oldl, oldt);
// TabViews base their drawing based on their absolute position within the
// window. When hardware accelerated, we need to recreate their display list
// when they scroll
if (isHardwareAccelerated()) {
int count = mContentView.getChildCount();
for (int i = 0; i < count; i++) {
mContentView.getChildAt(i).invalidate();
}
}
}
class TabLayout extends LinearLayout {
public TabLayout(Context context) {
super(context);
setChildrenDrawingOrderEnabled(true);
}
@Override
protected void onMeasure(int hspec, int vspec) {
super.onMeasure(hspec, vspec);
int w = getMeasuredWidth();
w -= Math.max(0, mContentView.getChildCount() - 1) * mTabOverlap;
setMeasuredDimension(w, getMeasuredHeight());
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if (getChildCount() > 1) {
int nextLeft = getChildAt(0).getRight() - mTabOverlap;
for (int i = 1; i < getChildCount(); i++) {
View tab = getChildAt(i);
int w = tab.getRight() - tab.getLeft();
tab.layout(nextLeft, tab.getTop(), nextLeft + w, tab.getBottom());
nextLeft += w - mTabOverlap;
}
}
}
@Override
protected int getChildDrawingOrder(int count, int i) {
int next = -1;
if ((i == (count - 1)) && (mSelected >= 0) && (mSelected < count)) {
next = mSelected;
} else {
next = count - i - 1;
if (next <= mSelected && next > 0) {
next--;
}
}
return next;
}
}
}