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在Android中使用RecyclerView创建的列表上滑动以显示操作按钮_Android_Android Recyclerview_Swipe - Fatal编程技术网

在Android中使用RecyclerView创建的列表上滑动以显示操作按钮

在Android中使用RecyclerView创建的列表上滑动以显示操作按钮,android,android-recyclerview,swipe,Android,Android Recyclerview,Swipe,我的应用程序的主要活动有一个自定义列表,每个列表项都应该在左扫时显示一个与其关联的操作按钮,并在同一列表项再次向右扫时隐藏该按钮。现在,我试图通过创建swipe detector类,然后将其设置为ItemHolder类中列表项的触摸侦听器,来检测每个列表项的滑动事件 但是,由于RecyclerView是可滚动的,所以在单个列表项上的滑动不会被检测到。如何检测单个列表项上的滑动 MainActivity-onCreate() 滑动检测适用于除RecyclerView列表项(或任何其他可滚动视图的子

我的应用程序的主要活动有一个自定义列表,每个列表项都应该在左扫时显示一个与其关联的操作按钮,并在同一列表项再次向右扫时隐藏该按钮。现在,我试图通过创建swipe detector类,然后将其设置为ItemHolder类中列表项的触摸侦听器,来检测每个列表项的滑动事件

但是,由于RecyclerView是可滚动的,所以在单个列表项上的滑动不会被检测到。如何检测单个列表项上的滑动

MainActivity-onCreate()


滑动检测适用于除RecyclerView列表项(或任何其他可滚动视图的子视图)之外的任何其他视图。如何检测列表项上的滑动?

问题已经解决,但我不知道这是否是正确的方法,但它确实有效。事情是这样的-

使用两种方法创建一个界面SwipeActions,这两种方法将用于左右滑动的回调

开关动作

public interface SwipeActions {
    public void onLeftSwipe(MotionEvent e);
    public void onRightSwipe(MotionEvent e);
}
然后将SwipeAction作为SwipedTector的属性之一,然后在构造函数中将其初始化

public class SwipeDetector implements View.OnTouchListener {
    static final int MIN_DISTANCE = 50;
    private float downX, downY, upX, upY;
    public SwipeActions swipeActions;

    public SwipeDetector(SwipeActions swipeActions) {
        this.swipeActions = swipeActions;
    }

    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN: {
                downX = event.getX();
                downY = event.getY();
            }
            case MotionEvent.ACTION_UP: {
                upX = event.getX();
                upY = event.getY();

                float deltaX = downX - upX;
                float deltaY = downY - upY;

                if ( Math.abs(deltaX) > MIN_DISTANCE){
                    if ( deltaX < 0){
                        swipeActions.onRightSwipe(event);
                        return true;
                    }
                    if ( deltaX > 0){
                        swipeActions.onLeftSwipe(event);
                        return true;
                    }
                } else{
                    Log.i("Swipe Detector","Swipe was only " + Math.abs(deltaX) + " long, need at least " + MIN_DISTANCE);
                }
            }
        }

        return false;
    }
}
public SubjectHolder(Context context, View itemView) {
    super(itemView);

    this.subjectTextView = (TextView) itemView.findViewById(R.id.name);

    SwipeDetector swipeDetector = new SwipeDetector();
    itemView.setOnTouchListener(swipeDetector);
}
public interface SwipeActions {
    public void onLeftSwipe(MotionEvent e);
    public void onRightSwipe(MotionEvent e);
}
public class SwipeDetector implements View.OnTouchListener {
    static final int MIN_DISTANCE = 50;
    private float downX, downY, upX, upY;
    public SwipeActions swipeActions;

    public SwipeDetector(SwipeActions swipeActions) {
        this.swipeActions = swipeActions;
    }

    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN: {
                downX = event.getX();
                downY = event.getY();
            }
            case MotionEvent.ACTION_UP: {
                upX = event.getX();
                upY = event.getY();

                float deltaX = downX - upX;
                float deltaY = downY - upY;

                if ( Math.abs(deltaX) > MIN_DISTANCE){
                    if ( deltaX < 0){
                        swipeActions.onRightSwipe(event);
                        return true;
                    }
                    if ( deltaX > 0){
                        swipeActions.onLeftSwipe(event);
                        return true;
                    }
                } else{
                    Log.i("Swipe Detector","Swipe was only " + Math.abs(deltaX) + " long, need at least " + MIN_DISTANCE);
                }
            }
        }

        return false;
    }
}
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main_recycler);

    ArrayList<Subject> subjects = new ArrayList<>();

    subjects.add(new Subject(1, "Physics"));
    subjects.add(new Subject(2, "Chemistry"));
    subjects.add(new Subject(3, "Biology"));

    RecyclerView recyclerView = (RecyclerView) findViewById(R.id.subject_recycler_list_view);

    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
    SubjectRecyclerListAdapter adapter = new SubjectRecyclerListAdapter(getApplicationContext(), R.layout.row_layout , subjects);
    SwipeDetector swipeDetector = new SwipeDetector(new SwipeActions() {
        @Override
        public void onLeftSwipe(MotionEvent evnt) {
            View childView = recyclerView.findChildViewUnder(evnt.getX(), evnt.getY());
            if(childView != null) {
                // Perform your action on childView (Swiped List Item)
            }
            else {
                Log.i("Main Recycler Activity", "Child View is Null");
            }
        }

        @Override
        public void onRightSwipe(MotionEvent evnt) {
            View childView = recyclerView.findChildViewUnder(evnt.getX(), evnt.getY());
            if(childView != null) {
                if(swipedViews.contains(childView)) {
                    // Perform your action on childView (Swiped List Item)
                }
            }
            else {
                Log.i("Main Recycler Activity", "Child View is Null");
            }
        }
    });

    recyclerView.setOnTouchListener(swipeDetector);
    recyclerView.setAdapter(adapter);
    recyclerView.setLayoutManager(layoutManager);
}
public SubjectHolder(Context context, View itemView) {
    super(itemView);

    this.subjectTextView = (TextView) itemView.findViewById(R.id.name);
}