1. 在我的应用程序中，我在 ListView 中添加了滑动以关闭项目以及撤消选项。

要求:

1. 我想在 Listview 中添加来自服务器的部分标题，如 Group1、Group2 等。

滑动以撤消取消的代码。请帮助我实现我的要求。 Link i referred

ListviewActivity.class

package com.swipe.delete;

import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.hudomju.swipe.SwipeToDismissTouchListener;
import com.hudomju.swipe.adapter.ListViewAdapter;

import java.util.ArrayList;
import java.util.List;

import static android.widget.Toast.LENGTH_SHORT;

public class ListViewActivity extends Activity {

    private static final int TIME_TO_AUTOMATICALLY_DISMISS_ITEM = 3000;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.list_view_activity);
        init((ListView) findViewById(R.id.list_view));
    }

    private void init(ListView listView) {
        final MyBaseAdapter adapter = new MyBaseAdapter();
        listView.setAdapter(adapter);
        final SwipeToDismissTouchListener<ListViewAdapter> touchListener =
                new SwipeToDismissTouchListener<>(
                        new ListViewAdapter(listView),
                        new SwipeToDismissTouchListener.DismissCallbacks<ListViewAdapter>() {
                            @Override
                            public boolean canDismiss(int position) {
                                return true;
                            }

                            @Override
                            public void onPendingDismiss(ListViewAdapter recyclerView, int position) {

                            }

                            @Override
                            public void onDismiss(ListViewAdapter view, int position) {
                                adapter.remove(position);
                            }
                        });

        touchListener.setDismissDelay(TIME_TO_AUTOMATICALLY_DISMISS_ITEM);
        listView.setOnTouchListener(touchListener);
        // Setting this scroll listener is required to ensure that during ListView scrolling,
        // we don't look for swipes.
        listView.setOnScrollListener((AbsListView.OnScrollListener) touchListener.makeScrollListener());
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (touchListener.existPendingDismisses()) {
                    touchListener.undoPendingDismiss();
                } else {
                    Toast.makeText(ListViewActivity.this, "Position " + position, LENGTH_SHORT).show();
                }
            }
        });
    }

    static class MyBaseAdapter extends BaseAdapter {

        private static final int SIZE = 100;

        private final List<String> mDataSet = new ArrayList<>();

        MyBaseAdapter() {
            for (int i = 0; i < SIZE; i++)
                mDataSet.add(i, "This is row number " + i);
        }

        @Override
        public int getCount() {
            return mDataSet.size();
        }

        @Override
        public String getItem(int position) {
            return mDataSet.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        public void remove(int position) {
            mDataSet.remove(position);
            notifyDataSetChanged();
        }

        static class ViewHolder {
            TextView dataTextView;
            ViewHolder(View view) {
                dataTextView = (TextView) view.findViewById(R.id.txt_data);
                view.setTag(this);
            }
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {

            ViewHolder viewHolder = convertView == null
                    ? new ViewHolder(convertView = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.list_item, parent, false))
                    : (ViewHolder) convertView.getTag();

            viewHolder.dataTextView.setText(mDataSet.get(position));
            return convertView;
        }
    }
}

SwipeToDismissTouchListener.class

package com.swipe.Delete;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ValueAnimator;
import android.graphics.Rect;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.ListView;



public class SwipeToDismissTouchListener<SomeCollectionView extends ViewAdapter> implements
        View.OnTouchListener {

    // Cached ViewConfiguration and system-wide constant values
    private final int mSlop;
    private final int mMinFlingVelocity;
    private final int mMaxFlingVelocity;
    private final long mAnimationTime;

    // Fixed properties
    private final SomeCollectionView mRecyclerView;
    private final DismissCallbacks<SomeCollectionView> mCallbacks;
    private int mViewWidth = 1; // 1 and not 0 to prevent dividing by zero

    // Transient properties
    private PendingDismissData mPendingDismiss;
    private float mDownX;
    private float mDownY;
    private boolean mSwiping;
    private int mSwipingSlop;
    private VelocityTracker mVelocityTracker;
    private int mDownPosition;
    private RowContainer mRowContainer;
    private boolean mPaused;

    // Handler to dismiss pending items after a delay
    private final Handler mHandler;
    private final Runnable mDismissRunnable = new Runnable() {
        @Override
        public void run() {
            processPendingDismisses();
        }
    };
    private long mDismissDelayMillis = -1; // negative to disable automatic dismissing

    public class RowContainer {

        final View container;
        final View dataContainer;
        final View undoContainer;
        boolean dataContainerHasBeenDismissed;

        public RowContainer(ViewGroup container) {
            this.container = container;
            dataContainer = container.getChildAt(0);
            undoContainer = container.getChildAt(1);
            dataContainerHasBeenDismissed = false;
        }

        View getCurrentSwipingView() {
            return dataContainerHasBeenDismissed ? undoContainer: dataContainer;
        }

    }

    /**
     * The callback interface used by {@link SwipeToDismissTouchListener} to inform its client
     * about a successful dismissal of one or more list item positions.
     */
    public interface DismissCallbacks<SomeCollectionView extends ViewAdapter> {
        /**
         * Called to determine whether the given position can be dismissed.
         */
        boolean canDismiss(int position);

        /**
         * Called when an item is swiped away by the user and the undo layout is completely visible.
         * Do NOT remove the list item yet, that should be done in { #onDismiss(com.hudomju.swipe.adapter.ViewAdapter, int)}
         * This may also be called immediately before and item is completely dismissed.
         *
         * @param recyclerView The originating {android.support.v7.widget.RecyclerView}.
         * @param position The position of the dismissed item.
         */
        void onPendingDismiss(SomeCollectionView recyclerView, int position);

        /**
         * Called when the item is completely dismissed and removed from the list, after the undo layout is hidden.
         *
         * @param recyclerView The originating { android.support.v7.widget.RecyclerView}.
         * @param position The position of the dismissed item.
         */
        void onDismiss(SomeCollectionView recyclerView, int position);
    }

    /**
     * Constructs a new swipe-to-dismiss touch listener for the given list view.
     *
     * @param recyclerView  The list view whose items should be dismissable.
     * @param callbacks The callback to trigger when the user has indicated that she would like to
     *                  dismiss one or more list items.
     */
    public SwipeToDismissTouchListener(SomeCollectionView recyclerView,
                                       DismissCallbacks<SomeCollectionView> callbacks) {
        ViewConfiguration vc = ViewConfiguration.get(recyclerView.getContext());
        mSlop = vc.getScaledTouchSlop();
        mMinFlingVelocity = vc.getScaledMinimumFlingVelocity() * 16;
        mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
        mAnimationTime = recyclerView.getContext().getResources().getInteger(
                android.R.integer.config_shortAnimTime);
        mRecyclerView = recyclerView;
        mCallbacks = callbacks;
        mHandler = new Handler();
    }

    /**
     * Enables or disables (pauses or resumes) watching for swipe-to-dismiss gestures.
     *
     * @param enabled Whether or not to watch for gestures.
     */
    public void setEnabled(boolean enabled) {
        mPaused = !enabled;
    }

    /**
     * Set the delay after which the pending items will be dismissed when there was no user action.
     * Set to a negative value to disable automatic dismissing items.
     * @param dismissDelayMillis The delay between onPendingDismiss and onDismiss calls, in milliseconds.
     */
    public void setDismissDelay(long dismissDelayMillis) {
        this.mDismissDelayMillis = dismissDelayMillis;
    }

    /**
     * Returns an {@link AbsListView.OnScrollListener} to be added to the {@link
     * ListView} using {@link ListView#setOnScrollListener(AbsListView.OnScrollListener)}.
     * If a scroll listener is already assigned, the caller should still pass scroll changes through
     * to this listener. This will ensure that this {@link SwipeToDismissTouchListener} is
     * paused during list view scrolling.</p>
     *
     * @see SwipeToDismissTouchListener
     */
    public Object makeScrollListener() {
        return mRecyclerView.makeScrollListener(new AbsListView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(AbsListView absListView, int scrollState) {
                processPendingDismisses();
                setEnabled(scrollState != AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
            }

            @Override
            public void onScroll(AbsListView absListView, int i, int i1, int i2) {
            }
        });
    }

    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
        if (mViewWidth < 2) {
            mViewWidth = mRecyclerView.getWidth();
        }

        switch (motionEvent.getActionMasked()) {
            case MotionEvent.ACTION_DOWN: {
                if (mPaused) {
                    return false;
                }

                // TODO: ensure this is a finger, and set a flag

                // Find the child view that was touched (perform a hit test)
                Rect rect = new Rect();
                int childCount = mRecyclerView.getChildCount();
                int[] listViewCoords = new int[2];
                mRecyclerView.getLocationOnScreen(listViewCoords);
                int x = (int) motionEvent.getRawX() - listViewCoords[0];
                int y = (int) motionEvent.getRawY() - listViewCoords[1];
                View child;
                for (int i = 0; i < childCount; i++) {
                    child = mRecyclerView.getChildAt(i);
                    child.getHitRect(rect);
                    if (rect.contains(x, y)) {
                        assert child instanceof ViewGroup &&
                                ((ViewGroup) child).getChildCount() == 2 :
                                "Each child needs to extend from ViewGroup and have two children";

                        boolean dataContainerHasBeenDismissed = mPendingDismiss != null &&
                                mPendingDismiss.position == mRecyclerView.getChildPosition(child) &&
                                mPendingDismiss.rowContainer.dataContainerHasBeenDismissed;
                        mRowContainer = new RowContainer((ViewGroup) child);
                        mRowContainer.dataContainerHasBeenDismissed = dataContainerHasBeenDismissed;
                        break;
                    }
                }

                if (mRowContainer != null) {
                    mDownX = motionEvent.getRawX();
                    mDownY = motionEvent.getRawY();
                    mDownPosition = mRecyclerView.getChildPosition(mRowContainer.container);
                    if (mCallbacks.canDismiss(mDownPosition)) {
                        mVelocityTracker = VelocityTracker.obtain();
                        mVelocityTracker.addMovement(motionEvent);
                    } else {
                        mRowContainer = null;
                    }
                }
                return false;
            }

            case MotionEvent.ACTION_CANCEL: {
                if (mVelocityTracker == null) {
                    break;
                }

                if (mRowContainer != null && mSwiping) {
                    // cancel
                    mRowContainer.getCurrentSwipingView()
                            .animate()
                            .translationX(0)
                            .alpha(1)
                            .setDuration(mAnimationTime)
                            .setListener(null);
                }
                mVelocityTracker.recycle();
                mVelocityTracker = null;
                mDownX = 0;
                mDownY = 0;
                mRowContainer = null;
                mDownPosition = ListView.INVALID_POSITION;
                mSwiping = false;
                break;
            }

            case MotionEvent.ACTION_UP: {
                if (mVelocityTracker == null) {
                    break;
                }

                float deltaX = motionEvent.getRawX() - mDownX;
                mVelocityTracker.addMovement(motionEvent);
                mVelocityTracker.computeCurrentVelocity(1000);
                float velocityX = mVelocityTracker.getXVelocity();
                float absVelocityX = Math.abs(velocityX);
                float absVelocityY = Math.abs(mVelocityTracker.getYVelocity());
                boolean dismiss = false;
                boolean dismissRight = false;
                if (Math.abs(deltaX) > mViewWidth / 2 && mSwiping) {
                    dismiss = true;
                    dismissRight = deltaX > 0;
                } else if (mMinFlingVelocity <= absVelocityX && absVelocityX <= mMaxFlingVelocity
                        && absVelocityY < absVelocityX && mSwiping) {
                    // dismiss only if flinging in the same direction as dragging
                    dismiss = (velocityX < 0) == (deltaX < 0);
                    dismissRight = mVelocityTracker.getXVelocity() > 0;
                }
                if (dismiss && mDownPosition != ListView.INVALID_POSITION) {
                    // dismiss
                    final RowContainer downView = mRowContainer; // mDownView gets null'd before animation ends
                    final int downPosition = mDownPosition;
                    mRowContainer.getCurrentSwipingView()
                            .animate()
                            .translationX(dismissRight ? mViewWidth : -mViewWidth)
                            .alpha(0)
                            .setDuration(mAnimationTime)
                            .setListener(new AnimatorListenerAdapter() {
                                @Override
                                public void onAnimationEnd(Animator animation) {
                                    performDismiss(downView, downPosition);
                                }
                            });
                } else {
                    // cancel
                    mRowContainer.getCurrentSwipingView()
                            .animate()
                            .translationX(0)
                            .alpha(1)
                            .setDuration(mAnimationTime)
                            .setListener(null);
                }
                mVelocityTracker.recycle();
                mVelocityTracker = null;
                mDownX = 0;
                mDownY = 0;
                mRowContainer = null;
                mDownPosition = ListView.INVALID_POSITION;
                mSwiping = false;
                break;
            }

            case MotionEvent.ACTION_MOVE: {
                if (mVelocityTracker == null || mPaused) {
                    break;
                }

                mVelocityTracker.addMovement(motionEvent);
                float deltaX = motionEvent.getRawX() - mDownX;
                float deltaY = motionEvent.getRawY() - mDownY;
                if (Math.abs(deltaX) > mSlop && Math.abs(deltaY) < Math.abs(deltaX) / 2) {
                    mSwiping = true;
                    mSwipingSlop = deltaX > 0 ? mSlop : -mSlop;
                    mRecyclerView.requestDisallowInterceptTouchEvent(true);

                    // Cancel ListView's touch (un-highlighting the item)
                    MotionEvent cancelEvent = MotionEvent.obtain(motionEvent);
                    cancelEvent.setAction(MotionEvent.ACTION_CANCEL |
                            (motionEvent.getActionIndex()
                                    << MotionEvent.ACTION_POINTER_INDEX_SHIFT));
                    mRecyclerView.onTouchEvent(cancelEvent);
                    cancelEvent.recycle();
                }

                if (mSwiping) {
                    mRowContainer.getCurrentSwipingView().setTranslationX(deltaX - mSwipingSlop);
                    mRowContainer.getCurrentSwipingView().setAlpha(Math.max(0f, Math.min(1f,
                            1f - 2f * Math.abs(deltaX) / mViewWidth)));
                    return true;
                }
                break;
            }
        }
        return false;
    }

    class PendingDismissData implements Comparable<PendingDismissData> {
        public int position;
        public RowContainer rowContainer;

        public PendingDismissData(int position, RowContainer rowContainer) {
            this.position = position;
            this.rowContainer= rowContainer;
        }

        @Override
        public int compareTo(@NonNull PendingDismissData other) {
            // Sort by descending position
            return other.position - position;
        }
    }

    private void performDismiss(RowContainer dismissView, int dismissPosition) {
        // Animate the dismissed list item to zero-height and fire the dismiss callback when
        // all dismissed list item animations have completed. This triggers layout on each animation
        // frame; in the future we may want to do something smarter and more performant.
        if (mPendingDismiss != null) {
            boolean dismissingDifferentRow = mPendingDismiss.position != dismissPosition;
            int newPosition = mPendingDismiss.position < dismissPosition ? dismissPosition-1 : dismissPosition;
            processPendingDismisses();
            if (dismissingDifferentRow) {
                addPendingDismiss(dismissView, newPosition);
            }
        } else {
            addPendingDismiss(dismissView, dismissPosition);
        }
    }

    private void addPendingDismiss(RowContainer dismissView, int dismissPosition) {
        dismissView.dataContainerHasBeenDismissed = true;
        dismissView.undoContainer.setVisibility(View.VISIBLE);
        mPendingDismiss = new PendingDismissData(dismissPosition, dismissView);
        // Notify the callbacks
        mCallbacks.onPendingDismiss(mRecyclerView, dismissPosition);
        // Automatically dismiss the item after a certain delay
        if(mDismissDelayMillis >= 0)
            mHandler.removeCallbacks(mDismissRunnable);
            mHandler.postDelayed(mDismissRunnable, mDismissDelayMillis);
    }

    /**
     * If a view was dismissed and the undo container is showing it will proceed with the final
     * dismiss of the item.
     * @return whether there were any pending rows to be dismissed.
     */
    public boolean processPendingDismisses() {
        boolean existPendingDismisses = existPendingDismisses();
        if (existPendingDismisses) processPendingDismisses(mPendingDismiss);
        return existPendingDismisses;
    }

    /**
     * Whether a row has been dismissed and is waiting for confirmation
     * @return whether there are any pending rows to be dismissed.
     */
    public boolean existPendingDismisses() {
        return mPendingDismiss != null && mPendingDismiss.rowContainer.dataContainerHasBeenDismissed;
    }

    /**
     * If a view was dismissed and the undo container is showing it will undo and make the data
     * container reappear.
     * @return whether there were any pending rows to be dismissed.
     */
    public boolean undoPendingDismiss() {
        boolean existPendingDismisses = existPendingDismisses();
        if (existPendingDismisses) {
            mPendingDismiss.rowContainer.undoContainer.setVisibility(View.GONE);
            mPendingDismiss.rowContainer.dataContainer
                    .animate()
                    .translationX(0)
                    .alpha(1)
                    .setDuration(mAnimationTime)
                    .setListener(null);
            mPendingDismiss = null;
        }
        return existPendingDismisses;
    }

    private void processPendingDismisses(final PendingDismissData pendingDismissData) {
        mPendingDismiss = null;
        final ViewGroup.LayoutParams lp = pendingDismissData.rowContainer.container.getLayoutParams();
        final int originalHeight = pendingDismissData.rowContainer.container.getHeight();

        ValueAnimator animator = ValueAnimator.ofInt(originalHeight, 1).setDuration(mAnimationTime);

        animator.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                if (mCallbacks.canDismiss(pendingDismissData.position))
                    mCallbacks.onDismiss(mRecyclerView, pendingDismissData.position);
                pendingDismissData.rowContainer.dataContainer.post(new Runnable() {
                    @Override
                    public void run() {
                        pendingDismissData.rowContainer.dataContainer.setTranslationX(0);
                        pendingDismissData.rowContainer.dataContainer.setAlpha(1);
                        pendingDismissData.rowContainer.undoContainer.setVisibility(View.GONE);
                        pendingDismissData.rowContainer.undoContainer.setTranslationX(0);
                        pendingDismissData.rowContainer.undoContainer.setAlpha(1);

                        lp.height = originalHeight;
                        pendingDismissData.rowContainer.container.setLayoutParams(lp);
                    }
                });
            }
        });

        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                lp.height = (Integer) valueAnimator.getAnimatedValue();
                pendingDismissData.rowContainer.container.setLayoutParams(lp);
            }
        });

        animator.start();
    }
}

最佳答案

我已经更新并评论了您的代码以实现您想要的。首先检查 MyBaseAdapter() 构造函数，然后检查 getView() 方法。

Package com.swipe.delete;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.hudomju.swipe.SwipeToDismissTouchListener;
import com.hudomju.swipe.adapter.ListViewAdapter;

import java.util.ArrayList;
import java.util.List;

import static android.widget.Toast.LENGTH_SHORT;

public class ListViewActivity extends Activity {

    private static final int TIME_TO_AUTOMATICALLY_DISMISS_ITEM = 3000;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.list_view_activity);
        init((ListView) findViewById(R.id.list_view));
    }

    private void init(ListView listView) {
        final MyBaseAdapter adapter = new MyBaseAdapter();
        listView.setAdapter(adapter);
        final SwipeToDismissTouchListener<ListViewAdapter> touchListener =
                new SwipeToDismissTouchListener<>(
                        new ListViewAdapter(listView),
                        new SwipeToDismissTouchListener.DismissCallbacks<ListViewAdapter>() {
                            @Override
                            public boolean canDismiss(int position) {
                                return true;
                            }

                            @Override
                            public void onPendingDismiss(ListViewAdapter recyclerView, int position) {

                            }

                            @Override
                            public void onDismiss(ListViewAdapter view, int position) {
                                adapter.remove(position);
                            }
                        });

        touchListener.setDismissDelay(TIME_TO_AUTOMATICALLY_DISMISS_ITEM);
        listView.setOnTouchListener(touchListener);
        // Setting this scroll listener is required to ensure that during ListView scrolling,
        // we don't look for swipes.
        listView.setOnScrollListener((AbsListView.OnScrollListener) touchListener.makeScrollListener());
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (touchListener.existPendingDismisses()) {
                    touchListener.undoPendingDismiss();
                } else {
                    Toast.makeText(ListViewActivity.this, "Position " + position, LENGTH_SHORT).show();
                }
            }
        });
    }

    static class MyBaseAdapter extends BaseAdapter {

        private static final int SIZE = 100;

        private final List<String> mDataSet = new ArrayList<>();

        MyBaseAdapter() {
            for (int i = 0; i < 5; i++){
            // You should add an object containing type of view like section or sectionHeader along with your string.
            // Here i am just using string search to detect whether it is sectionHeader or section. have a look at getView() Method
                mDataSet.add("This is Section Header " + i);
                for (int e = 0; e < SIZE; i++){
                    mDataSet.add(i, "This is section " + e);
                }
            }
        }

        @Override
        public int getCount() {
            return mDataSet.size();
        }

        @Override
        public String getItem(int position) {
            return mDataSet.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        public void remove(int position) {
            mDataSet.remove(position);
            notifyDataSetChanged();
        }

        static class ViewHolder {
            TextView dataTextView;
            ViewHolder(View view) {
                dataTextView = (TextView) view.findViewById(R.id.txt_data);
                view.setTag(this);
            }
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {

            ViewHolder viewHolder = convertView == null
                    ? new ViewHolder(convertView = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.list_item, parent, false))
                    : (ViewHolder) convertView.getTag();

            viewHolder.dataTextView.setText(mDataSet.get(position));
            if(mDataSet.get(position).indexof("Section Header") != -1){
                // This is your sectionHeader
                // Customize you sectionHeader UI here
                // Ideally you should use object here so (object.type == 1) can determine whether this is a sectionHeader or header
            }else{
                // This is your section
                // Customize you section UI here
            }

            return convertView;
        }
    }
}

希望对你有帮助。

关于android - 可以在 ListView 中添加来自服务器的节标题，使用滑动来删除和撤消项目，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/42408458/