| /* |
| * Copyright (C) 2017 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.systemui.statusbar.car; |
| |
| import android.content.Context; |
| import android.content.res.TypedArray; |
| import android.database.DataSetObserver; |
| import android.graphics.Canvas; |
| import android.graphics.Paint; |
| import android.support.v4.view.PagerAdapter; |
| import android.support.v4.view.ViewPager; |
| import android.util.AttributeSet; |
| import android.util.Log; |
| import android.util.TypedValue; |
| import android.view.Gravity; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.view.ViewParent; |
| |
| import com.android.systemui.R; |
| |
| import java.lang.ref.WeakReference; |
| |
| /** |
| * Displays the dots underneath the ViewPager on the lock screen. This is really just a simplified |
| * version of PagerTitleStrip. We don't inherit from there because it's impossible to bypass some |
| * of the overriden logic in that class. |
| */ |
| public class PageIndicator extends View { |
| private static final String TAG = "PageIndicator"; |
| // These can be made a styleable attribute in the future if necessary. |
| private static final int SELECTED_COLOR = 0xFFF5F5F5; // grey 100 |
| private static final int UNSELECTED_COLOR = 0xFFBDBDBD; // grey 400 |
| private final PageListener mPageListener = new PageListener(); |
| |
| private ViewPager mPager; |
| private WeakReference<PagerAdapter> mWatchingAdapter; |
| |
| private int mPageCount; |
| private int mCurrentPosition; |
| private Paint mPaint; |
| private int mRadius; |
| private int mStep; |
| |
| public PageIndicator(Context context) { |
| super(context); |
| init(); |
| } |
| |
| public PageIndicator(Context context, AttributeSet attrs) { |
| super(context, attrs); |
| init(); |
| } |
| |
| private void init() { |
| mPaint = new Paint(Paint.ANTI_ALIAS_FLAG); |
| mPaint.setStyle(Paint.Style.FILL); |
| mRadius = getResources().getDimensionPixelSize(R.dimen.car_page_indicator_dot_diameter) / 2; |
| mStep = mRadius * 3; |
| } |
| |
| public void setupWithViewPager(ViewPager pager) { |
| mPager = pager; |
| |
| final PagerAdapter adapter = (PagerAdapter) pager.getAdapter(); |
| pager.addOnPageChangeListener(mPageListener); |
| pager.addOnAdapterChangeListener(mPageListener); |
| updateAdapter(mWatchingAdapter != null ? mWatchingAdapter.get() : null, adapter); |
| invalidate(); |
| } |
| |
| @Override |
| protected void onDetachedFromWindow() { |
| super.onDetachedFromWindow(); |
| if (mPager != null) { |
| updateAdapter(mPager.getAdapter(), null); |
| mPager.removeOnPageChangeListener(mPageListener); |
| mPager.removeOnAdapterChangeListener(mPageListener); |
| mPager = null; |
| } |
| } |
| |
| @Override |
| protected void onDraw(Canvas canvas) { |
| super.onDraw(canvas); |
| |
| int x = canvas.getWidth() / 2 - (mPageCount / 2) * mStep; |
| int y = canvas.getHeight() / 2; |
| |
| for (int i = 0; i < mPageCount; i++) { |
| if (i == mCurrentPosition) { |
| mPaint.setColor(SELECTED_COLOR); |
| } else { |
| mPaint.setColor(UNSELECTED_COLOR); |
| } |
| |
| canvas.drawCircle(x, y, mRadius, mPaint); |
| x += mStep; |
| } |
| } |
| |
| void updateAdapter(PagerAdapter oldAdapter, PagerAdapter newAdapter) { |
| if (oldAdapter != null) { |
| oldAdapter.unregisterDataSetObserver(mPageListener); |
| mWatchingAdapter = null; |
| } |
| |
| if (newAdapter != null) { |
| newAdapter.registerDataSetObserver(mPageListener); |
| mWatchingAdapter = new WeakReference<>(newAdapter); |
| } |
| |
| updateDots(); |
| |
| if (mPager != null) { |
| requestLayout(); |
| } |
| } |
| |
| private <T> T getRef(WeakReference<T> weakRef) { |
| if (weakRef == null) { |
| return null; |
| } |
| return weakRef.get(); |
| } |
| |
| private void updateDots() { |
| PagerAdapter adapter = getRef(mWatchingAdapter); |
| if (adapter == null) { |
| return; |
| } |
| |
| int count = adapter.getCount(); |
| if (mPageCount == count) { |
| // Nothing to be done. |
| return; |
| } |
| |
| mPageCount = count; |
| mCurrentPosition = 0; |
| invalidate(); |
| } |
| |
| private class PageListener extends DataSetObserver implements ViewPager.OnPageChangeListener, |
| ViewPager.OnAdapterChangeListener { |
| |
| @Override |
| public void onPageScrolled(int unused1, float unused2, int unused3) { } |
| |
| @Override |
| public void onPageSelected(int position) { |
| if (mCurrentPosition == position) { |
| return; |
| } |
| |
| if (mPageCount <= position) { |
| Log.e(TAG, "Position out of bounds, position=" + position + " size=" + mPageCount); |
| return; |
| } |
| |
| mCurrentPosition = position; |
| invalidate(); |
| } |
| |
| @Override |
| public void onPageScrollStateChanged(int state) { } |
| |
| @Override |
| public void onAdapterChanged(ViewPager viewPager, PagerAdapter oldAdapter, |
| PagerAdapter newAdapter) { |
| updateAdapter(oldAdapter, newAdapter); |
| } |
| |
| @Override |
| public void onChanged() { |
| updateDots(); |
| } |
| } |
| } |