| /* |
| * Copyright (C) 2016 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.qs; |
| |
| import android.annotation.Nullable; |
| import android.content.Context; |
| import android.content.res.TypedArray; |
| import android.database.DataSetObserver; |
| import android.os.Handler; |
| import android.util.AttributeSet; |
| import android.view.View; |
| import android.widget.LinearLayout; |
| import android.widget.ListAdapter; |
| |
| import com.android.systemui.R; |
| |
| /** |
| * Similar to a ListView, but it will show only as many items as fit on screen and |
| * bind those instead of scrolling. |
| */ |
| public class AutoSizingList extends LinearLayout { |
| |
| private static final String TAG = "AutoSizingList"; |
| private final int mItemSize; |
| private final Handler mHandler; |
| |
| private ListAdapter mAdapter; |
| private int mCount; |
| private boolean mEnableAutoSizing; |
| |
| public AutoSizingList(Context context, @Nullable AttributeSet attrs) { |
| super(context, attrs); |
| |
| mHandler = new Handler(); |
| TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.AutoSizingList); |
| mItemSize = a.getDimensionPixelSize(R.styleable.AutoSizingList_itemHeight, 0); |
| mEnableAutoSizing = a.getBoolean(R.styleable.AutoSizingList_enableAutoSizing, true); |
| a.recycle(); |
| } |
| |
| public void setAdapter(ListAdapter adapter) { |
| if (mAdapter != null) { |
| mAdapter.unregisterDataSetObserver(mDataObserver); |
| } |
| mAdapter = adapter; |
| if (adapter != null) { |
| adapter.registerDataSetObserver(mDataObserver); |
| } |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| int requestedHeight = MeasureSpec.getSize(heightMeasureSpec); |
| if (requestedHeight != 0) { |
| int count = getItemCount(requestedHeight); |
| if (mCount != count) { |
| postRebindChildren(); |
| mCount = count; |
| } |
| } |
| super.onMeasure(widthMeasureSpec, heightMeasureSpec); |
| } |
| |
| private int getItemCount(int requestedHeight) { |
| int desiredCount = getDesiredCount(); |
| return mEnableAutoSizing ? Math.min(requestedHeight / mItemSize, desiredCount) |
| : desiredCount; |
| } |
| |
| private int getDesiredCount() { |
| return mAdapter != null ? mAdapter.getCount() : 0; |
| } |
| |
| private void postRebindChildren() { |
| mHandler.post(mBindChildren); |
| } |
| |
| private void rebindChildren() { |
| if (mAdapter == null) { |
| return; |
| } |
| for (int i = 0; i < mCount; i++) { |
| View v = i < getChildCount() ? getChildAt(i) : null; |
| View newView = mAdapter.getView(i, v, this); |
| if (newView != v) { |
| if (v != null) { |
| removeView(v); |
| } |
| addView(newView, i); |
| } |
| } |
| // Ditch extra views. |
| while (getChildCount() > mCount) { |
| removeViewAt(getChildCount() - 1); |
| } |
| } |
| |
| private final Runnable mBindChildren = new Runnable() { |
| @Override |
| public void run() { |
| rebindChildren(); |
| } |
| }; |
| |
| private final DataSetObserver mDataObserver = new DataSetObserver() { |
| @Override |
| public void onChanged() { |
| if (mCount > getDesiredCount()) { |
| mCount = getDesiredCount(); |
| } |
| postRebindChildren(); |
| } |
| |
| @Override |
| public void onInvalidated() { |
| postRebindChildren(); |
| } |
| }; |
| } |