java - 如何添加向右滑动打开抽屉导航

Question

我有标准的抽屉导航，要打开抽屉导航，您需要从左侧窗口向右滑动。我在不同的手机上尝试过这个，有些手机上有外壳，你不能真正向右滑动(相当困难)。所以我想添加一个滑动手势。因此，当您向右滑动时，抽屉就会打开。我找不到要刷的代码!我试着看，但一切似乎都很模糊。

  DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);

这是我的一些代码。如果您还需要什么请告诉我!!希望有人能解决这个问题!...

更新: 我已经找到了刷卡代码并创建了一个类。

import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;

public class OnSwipeTouchListener implements OnTouchListener {

    private final GestureDetector gestureDetector;

    public OnSwipeTouchListener (Context ctx){
        gestureDetector = new GestureDetector(ctx, new GestureListener());
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
    }

    private final class GestureListener extends SimpleOnGestureListener {

        private static final int SWIPE_THRESHOLD = 100;
        private static final int SWIPE_VELOCITY_THRESHOLD = 100;

        @Override
        public boolean onDown(MotionEvent e) {
            return true;
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            boolean result = false;
            try {
                float diffY = e2.getY() - e1.getY();
                float diffX = e2.getX() - e1.getX();
                if (Math.abs(diffX) > Math.abs(diffY)) {
                    if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffX > 0) {
                            onSwipeRight();
                        } else {
                            onSwipeLeft();
                        }
                    }
                    result = true;
                } 
                else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffY > 0) {
                            onSwipeBottom();
                        } else {
                            onSwipeTop();
                        }
                    }
                    result = true;

            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }
    }

    public void onSwipeRight() {
    }

    public void onSwipeLeft() {
    }

    public void onSwipeTop() {
    }

    public void onSwipeBottom() {
    }
}

这是我在 MainActivity 类中使​​用代码

 drawer.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {

            }
        });
       drawer.setOnTouchListener(new OnSwipeTouchListener(MainActivity.this ) {
            public boolean onSwipeTop() {
                Toast.makeText(MainActivity.this, "top", Toast.LENGTH_SHORT).show();
                return true;
            }
            public boolean onSwipeRight() {
                DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
                drawer.openDrawer(GravityCompat.START);

                return true;
            }
            public boolean onSwipeLeft() {
                DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
                drawer.closeDrawer(GravityCompat.START);

                return true;
            }
            public boolean onSwipeBottom() {
                Toast.makeText(MainActivity.this, "bottom", Toast.LENGTH_SHORT).show();
                return true;
            }
        });

当我滑动时， toast 可以工作，但我尝试将 opendrawer 和 Closerdrawer 添加到左右滑动，但什么也没发生..

Answer 1

更改方法

public void onSwipeRight() {
    }

至

public abstract void onSwipeRight();

...

并使你的类也抽象

public abstract class OnSwipeTouchListener