Java tutorial
/* * Twidere - Twitter client for Android * * Copyright (C) 2012-2015 Mariotaku Lee <mariotaku.lee@gmail.com> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.mariotaku.twidere.fragment; import android.content.Context; import android.graphics.Rect; import android.os.Bundle; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.support.v4.app.FragmentActivity; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.RecyclerView.ItemDecoration; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.TextView; import org.mariotaku.twidere.R; import org.mariotaku.twidere.activity.iface.IControlBarActivity; import org.mariotaku.twidere.activity.iface.IControlBarActivity.ControlBarShowHideHelper; import org.mariotaku.twidere.adapter.LoadMoreSupportAdapter; import org.mariotaku.twidere.adapter.iface.ILoadMoreSupportAdapter.IndicatorPosition; import org.mariotaku.twidere.fragment.iface.RefreshScrollTopInterface; import org.mariotaku.twidere.util.ContentScrollHandler; import org.mariotaku.twidere.util.RecyclerViewScrollHandler; import org.mariotaku.twidere.util.SimpleDrawerCallback; import org.mariotaku.twidere.util.ThemeUtils; import org.mariotaku.twidere.util.TwidereColorUtils; import org.mariotaku.twidere.view.ExtendedSwipeRefreshLayout; import org.mariotaku.twidere.view.HeaderDrawerLayout; import org.mariotaku.twidere.view.iface.IExtendedView; /** * Created by mariotaku on 15/10/26. */ public abstract class AbsContentRecyclerViewFragment<A extends LoadMoreSupportAdapter, L extends RecyclerView.LayoutManager> extends BaseSupportFragment implements SwipeRefreshLayout.OnRefreshListener, HeaderDrawerLayout.DrawerCallback, RefreshScrollTopInterface, IControlBarActivity.ControlBarOffsetListener, ContentScrollHandler.ContentListSupport, ControlBarShowHideHelper.ControlBarAnimationListener { private View mProgressContainer; private SwipeRefreshLayout mSwipeRefreshLayout; private RecyclerView mRecyclerView; private View mErrorContainer; private L mLayoutManager; @SuppressWarnings("NullableProblems") @NonNull private A mAdapter; @Nullable private ItemDecoration mItemDecoration; // Callbacks and listeners private SimpleDrawerCallback mDrawerCallback; protected RecyclerViewScrollHandler mScrollListener; // Data fields private Rect mSystemWindowsInsets = new Rect(); @Override public boolean canScroll(float dy) { return mDrawerCallback.canScroll(dy); } @Override public void cancelTouch() { mDrawerCallback.cancelTouch(); } @Override public void fling(float velocity) { mDrawerCallback.fling(velocity); } @Override public boolean isScrollContent(float x, float y) { return mDrawerCallback.isScrollContent(x, y); } @Override public void onControlBarOffsetChanged(IControlBarActivity activity, float offset) { updateRefreshProgressOffset(); } @Override public void onRefresh() { triggerRefresh(); } @Override public void setUserVisibleHint(boolean isVisibleToUser) { super.setUserVisibleHint(isVisibleToUser); updateRefreshProgressOffset(); } @Override public void scrollBy(float dy) { mDrawerCallback.scrollBy(dy); } @Override public boolean scrollToStart() { scrollToPositionWithOffset(0, 0); mRecyclerView.stopScroll(); setControlVisible(true); return true; } protected abstract void scrollToPositionWithOffset(int position, int offset); @Override public void onControlBarVisibleAnimationFinish(boolean visible) { updateRefreshProgressOffset(); } @Override public void setControlVisible(boolean visible) { final FragmentActivity activity = getActivity(); if (activity instanceof IControlBarActivity) { //TODO hide only if top > actionBar.height final L manager = getLayoutManager(); if (manager.getChildCount() == 0) return; final View firstView = manager.getChildAt(0); final IControlBarActivity controlBarActivity = (IControlBarActivity) activity; if (manager.getPosition(firstView) != 0) { controlBarActivity.setControlBarVisibleAnimate(visible, this); return; } final int top = firstView.getTop(); controlBarActivity.setControlBarVisibleAnimate(visible || top > 0, this); } } @Override public boolean shouldLayoutHeaderBottom() { return mDrawerCallback.shouldLayoutHeaderBottom(); } @Override public void topChanged(int offset) { mDrawerCallback.topChanged(offset); } @NonNull @Override public A getAdapter() { return mAdapter; } @Override public abstract boolean isRefreshing(); public L getLayoutManager() { return mLayoutManager; } public void setRefreshing(final boolean refreshing) { final boolean currentRefreshing = mSwipeRefreshLayout.isRefreshing(); if (!currentRefreshing) { updateRefreshProgressOffset(); } if (refreshing == currentRefreshing) return; final boolean layoutRefreshing = refreshing && mAdapter.getLoadMoreIndicatorPosition() != IndicatorPosition.NONE; mSwipeRefreshLayout.setRefreshing(layoutRefreshing); } @Override public void onLoadMoreContents(@IndicatorPosition int position) { setLoadMoreIndicatorPosition(position); setRefreshEnabled(position == IndicatorPosition.NONE); } public final RecyclerView getRecyclerView() { return mRecyclerView; } @Override public void onAttach(Context context) { super.onAttach(context); if (context instanceof IControlBarActivity) { ((IControlBarActivity) context).registerControlBarOffsetListener(this); } } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { return inflater.inflate(R.layout.fragment_content_recyclerview, container, false); } @Override public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); mDrawerCallback = new SimpleDrawerCallback(mRecyclerView); final View view = getView(); assert view != null; final Context context = view.getContext(); final int backgroundColor = ThemeUtils.getThemeBackgroundColor(context); final int colorRes = TwidereColorUtils.getContrastYIQ(backgroundColor, R.color.bg_refresh_progress_color_light, R.color.bg_refresh_progress_color_dark); mSwipeRefreshLayout.setOnRefreshListener(this); mSwipeRefreshLayout.setProgressBackgroundColorSchemeResource(colorRes); mAdapter = onCreateAdapter(context); mLayoutManager = onCreateLayoutManager(context); mRecyclerView.setLayoutManager(mLayoutManager); mRecyclerView.setHasFixedSize(true); if (mSwipeRefreshLayout instanceof ExtendedSwipeRefreshLayout) { ((ExtendedSwipeRefreshLayout) mSwipeRefreshLayout) .setTouchInterceptor(new IExtendedView.TouchInterceptor() { @Override public boolean dispatchTouchEvent(View view, MotionEvent event) { return false; } @Override public boolean onInterceptTouchEvent(View view, MotionEvent event) { if (event.getActionMasked() == MotionEvent.ACTION_DOWN) { updateRefreshProgressOffset(); } return false; } @Override public boolean onTouchEvent(View view, MotionEvent event) { return false; } }); } setupRecyclerView(context, mRecyclerView); mRecyclerView.setAdapter(mAdapter); mScrollListener = new RecyclerViewScrollHandler(this, new RecyclerViewScrollHandler.RecyclerViewCallback(mRecyclerView)); mScrollListener.setTouchSlop(ViewConfiguration.get(context).getScaledTouchSlop()); mRecyclerView.setOnTouchListener(mScrollListener.getOnTouchListener()); } protected void setupRecyclerView(Context context, RecyclerView recyclerView) { mItemDecoration = createItemDecoration(context, recyclerView, getLayoutManager()); if (mItemDecoration != null) { recyclerView.addItemDecoration(mItemDecoration); } } @NonNull protected abstract L onCreateLayoutManager(Context context); @Override public void onStart() { super.onStart(); mRecyclerView.addOnScrollListener(mScrollListener); } @Override public void onStop() { mRecyclerView.removeOnScrollListener(mScrollListener); super.onStop(); } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); mProgressContainer = view.findViewById(R.id.progress_container); mSwipeRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.swipe_layout); mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view); mErrorContainer = view.findViewById(R.id.error_container); } @Override public void onDetach() { final FragmentActivity activity = getActivity(); if (activity instanceof IControlBarActivity) { ((IControlBarActivity) activity).unregisterControlBarOffsetListener(this); } super.onDetach(); } @NonNull protected Rect getExtraContentPadding() { return new Rect(); } @Override protected void fitSystemWindows(Rect insets) { final Rect extraPadding = getExtraContentPadding(); mRecyclerView.setPadding(insets.left + extraPadding.left, insets.top + extraPadding.top, insets.right + extraPadding.right, insets.bottom + extraPadding.bottom); mErrorContainer.setPadding(insets.left, insets.top, insets.right, insets.bottom); mProgressContainer.setPadding(insets.left, insets.top, insets.right, insets.bottom); mSystemWindowsInsets.set(insets); updateRefreshProgressOffset(); } public void setLoadMoreIndicatorPosition(@IndicatorPosition int position) { mAdapter.setLoadMoreIndicatorPosition(position); } public void setRefreshEnabled(boolean enabled) { mSwipeRefreshLayout.setEnabled(enabled); } @Override public boolean triggerRefresh() { return false; } @NonNull protected abstract A onCreateAdapter(Context context); @Nullable protected ItemDecoration createItemDecoration(Context context, RecyclerView recyclerView, L layoutManager) { return null; } @Nullable public final ItemDecoration getItemDecoration() { return mItemDecoration; } protected final void showContent() { mErrorContainer.setVisibility(View.GONE); mProgressContainer.setVisibility(View.GONE); mSwipeRefreshLayout.setVisibility(View.VISIBLE); } protected final void showProgress() { mErrorContainer.setVisibility(View.GONE); mProgressContainer.setVisibility(View.VISIBLE); mSwipeRefreshLayout.setVisibility(View.GONE); } protected final void showError(int icon, CharSequence text) { mErrorContainer.setVisibility(View.VISIBLE); mProgressContainer.setVisibility(View.GONE); mSwipeRefreshLayout.setVisibility(View.GONE); final ImageView errorIconView = (ImageView) mErrorContainer.findViewById(R.id.error_icon); final TextView errorTextView = (TextView) mErrorContainer.findViewById(R.id.error_text); errorIconView.setImageResource(icon); errorTextView.setText(text); } protected final void showEmpty(int icon, CharSequence text) { mErrorContainer.setVisibility(View.VISIBLE); mProgressContainer.setVisibility(View.GONE); mSwipeRefreshLayout.setVisibility(View.VISIBLE); final ImageView errorIconView = (ImageView) mErrorContainer.findViewById(R.id.error_icon); final TextView errorTextView = (TextView) mErrorContainer.findViewById(R.id.error_text); errorIconView.setImageResource(icon); errorTextView.setText(text); } protected void updateRefreshProgressOffset() { final FragmentActivity activity = getActivity(); final Rect insets = this.mSystemWindowsInsets; final SwipeRefreshLayout layout = this.mSwipeRefreshLayout; if (!(activity instanceof IControlBarActivity) || insets.top == 0 || layout == null || isRefreshing()) { return; } final int progressCircleDiameter = layout.getProgressCircleDiameter(); if (progressCircleDiameter == 0) return; final float density = getResources().getDisplayMetrics().density; final IControlBarActivity control = (IControlBarActivity) activity; final int controlBarOffsetPixels = Math .round(control.getControlBarHeight() * (1 - control.getControlBarOffset())); final int swipeStart = (insets.top - controlBarOffsetPixels) - progressCircleDiameter; // 64: SwipeRefreshLayout.DEFAULT_CIRCLE_TARGET final int swipeDistance = Math.round(64 * density); layout.setProgressViewOffset(false, swipeStart, swipeStart + swipeDistance); } }