我希望我的应用程序能够识别用户在手机屏幕上从右向左滑动。
如何做到这一点?
我希望我的应用程序能够识别用户在手机屏幕上从右向左滑动。
如何做到这一点?
当前回答
@Mirek Rusin的Kotlin版本在这里:
OnSwipeTouchListener。kt:
open class OnSwipeTouchListener(ctx: Context) : OnTouchListener {
private val gestureDetector: GestureDetector
companion object {
private val SWIPE_THRESHOLD = 100
private val SWIPE_VELOCITY_THRESHOLD = 100
}
init {
gestureDetector = GestureDetector(ctx, GestureListener())
}
override fun onTouch(v: View, event: MotionEvent): Boolean {
return gestureDetector.onTouchEvent(event)
}
private inner class GestureListener : SimpleOnGestureListener() {
override fun onDown(e: MotionEvent): Boolean {
return true
}
override fun onFling(e1: MotionEvent, e2: MotionEvent, velocityX: Float, velocityY: Float): Boolean {
var result = false
try {
val diffY = e2.y - e1.y
val diffX = e2.x - e1.x
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
}
}
open fun onSwipeRight() {}
open fun onSwipeLeft() {}
open fun onSwipeTop() {}
open fun onSwipeBottom() {}
}
用法:
view.setOnTouchListener(object : OnSwipeTouchListener(context) {
override fun onSwipeTop() {
super.onSwipeTop()
}
override fun onSwipeBottom() {
super.onSwipeBottom()
}
override fun onSwipeLeft() {
super.onSwipeLeft()
}
override fun onSwipeRight() {
super.onSwipeRight()
}
})
open关键字对我来说很重要……
其他回答
If you want to display some buttons with actions when an list item is swipe are a lot of libraries on the internet that have this behavior. I implemented the library that I found on the internet and I am very satisfied. It is very simple to use and very quick. I improved the original library and I added a new click listener for item click. Also I added font awesome library (http://fortawesome.github.io/Font-Awesome/) and now you can simply add a new item title and specify the icon name from font awesome.
这是github的链接
我知道从2012年开始有点晚了,但我希望它能帮助到一些人,因为我认为它比大多数答案都更短,更干净:
view.setOnTouchListener((v, event) -> {
int action = MotionEventCompat.getActionMasked(event);
switch(action) {
case (MotionEvent.ACTION_DOWN) :
Log.d(DEBUG_TAG,"Action was DOWN");
return true;
case (MotionEvent.ACTION_MOVE) :
Log.d(DEBUG_TAG,"Action was MOVE");
return true;
case (MotionEvent.ACTION_UP) :
Log.d(DEBUG_TAG,"Action was UP");
return true;
case (MotionEvent.ACTION_CANCEL) :
Log.d(DEBUG_TAG,"Action was CANCEL");
return true;
case (MotionEvent.ACTION_OUTSIDE) :
Log.d(DEBUG_TAG,"Movement occurred outside bounds " +
"of current screen element");
return true;
default :
return super.onTouchEvent(event);
}
});
当然,你可以只留下相关的手势。
src: https://developer.android.com/training/gestures/detector
我的解决方案与上述类似,但我将手势处理抽象为一个抽象类OnGestureRegisterListener.java,其中包括滑动、单击和长按手势。
OnGestureRegisterListener.java
public abstract class OnGestureRegisterListener implements View.OnTouchListener {
private final GestureDetector gestureDetector;
private View view;
public OnGestureRegisterListener(Context context) {
gestureDetector = new GestureDetector(context, new GestureListener());
}
@Override
public boolean onTouch(View view, MotionEvent event) {
this.view = view;
return gestureDetector.onTouchEvent(event);
}
public abstract void onSwipeRight(View view);
public abstract void onSwipeLeft(View view);
public abstract void onSwipeBottom(View view);
public abstract void onSwipeTop(View view);
public abstract void onClick(View view);
public abstract boolean onLongClick(View view);
private final class GestureListener extends GestureDetector.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 void onLongPress(MotionEvent e) {
onLongClick(view);
super.onLongPress(e);
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
onClick(view);
return super.onSingleTapUp(e);
}
@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(view);
} else {
onSwipeLeft(view);
}
result = true;
}
}
else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
if (diffY > 0) {
onSwipeBottom(view);
} else {
onSwipeTop(view);
}
result = true;
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}
}
像这样使用它。注意,您还可以轻松地传入您的View参数。
OnGestureRegisterListener onGestureRegisterListener = new OnGestureRegisterListener(this) {
public void onSwipeRight(View view) {
// Do something
}
public void onSwipeLeft(View view) {
// Do something
}
public void onSwipeBottom(View view) {
// Do something
}
public void onSwipeTop(View view) {
// Do something
}
public void onClick(View view) {
// Do something
}
public boolean onLongClick(View view) {
// Do something
return true;
}
};
Button button = findViewById(R.id.my_button);
button.setOnTouchListener(onGestureRegisterListener);
这个问题仍然存在。添加以下类:
private class SwipeFirstTouchListener implements View.OnTouchListener {
private final DirtyOnSwipeTouchListener swipe;
private final View.OnTouchListener delegate;
private SwipeFirstTouchListener(DirtyOnSwipeTouchListener swipe, View.OnTouchListener delegate) {
this.swipe = swipe;
this.delegate = delegate;
}
@Override
public boolean onTouch(View v, MotionEvent event) {
if (!swipe.onTouch(v, event)) {
// no a swipe, so lets try with the rest of the events
return delegate.onTouch(v, event);
}
return false;
}
}
and
private class DirtyOnSwipeTouchListener extends OnSwipeTouchListener {
private boolean dirty = false;
private OnSwipeTouchListener delegate;
public DirtyOnSwipeTouchListener(Context ctx, OnSwipeTouchListener delegate) {
super(ctx);
this.delegate = delegate;
}
private void reset() {
dirty = false;
}
public void onSwipeTop() {
dirty = true;
delegate.onSwipeTop();
}
public void onSwipeRight() {
dirty = true;
delegate.onSwipeRight();
}
public void onSwipeLeft() {
dirty = true;
delegate.onSwipeLeft();
}
public void onSwipeBottom() {
dirty = true;
delegate.onSwipeBottom();
}
@Override
public boolean onTouch(View v, MotionEvent event) {
try {
super.onTouch(v, event);
return dirty;
} finally {
dirty = false;
}
}
};
还有一个在网上找到的课程:
public class OnSwipeTouchListener implements OnTouchListener {
private static final String TAG = OnSwipeTouchListener.class.getName();
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 GestureDetector.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) {
Log.d(TAG, "Unexpected problem handling swipes, ignoring.", exception);
}
return result;
}
}
public void onSwipeRight() {
// Do nothing
}
public void onSwipeLeft() {
// Do nothing
}
public void onSwipeTop() {
// Do nothing
}
public void onSwipeBottom() {
// Do nothing
}
}
然后添加你自己的OnTouchListener和OnSwipeTouchListener,如下所示:
DirtyOnSwipeTouchListener swipe = new DirtyOnSwipeTouchListener(this, new OnSwipeTouchListener(this) {
public void onSwipeTop() {
// your code here
}
public void onSwipeRight() {
// your code here
}
public void onSwipeLeft() {
// your code here
}
public void onSwipeBottom() {
// your code here
}
});
View.OnTouchListener toggleListener = new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_UP) {
// your code here
return true;
} else if (event.getAction() == MotionEvent.ACTION_DOWN) {
// your code here
return true;
}
return false;
}
};
SwipeFirstTouchListener swipeFirstTouchListener = new SwipeFirstTouchListener(swipe, toggleListener);
myView.setOnTouchListener(swipeFirstTouchListener);
如果你还需要处理点击事件,这里做一些修改:
public class OnSwipeTouchListener implements OnTouchListener {
private final GestureDetector gestureDetector = new GestureDetector(new GestureListener());
public boolean onTouch(final View v, final 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 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) {
result = onSwipeRight();
} else {
result = onSwipeLeft();
}
}
} else {
if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
if (diffY > 0) {
result = onSwipeBottom();
} else {
result = onSwipeTop();
}
}
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}
public boolean onSwipeRight() {
return false;
}
public boolean onSwipeLeft() {
return false;
}
public boolean onSwipeTop() {
return false;
}
public boolean onSwipeBottom() {
return false;
}
}
以及示例用法:
background.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
toggleSomething();
}
});
background.setOnTouchListener(new OnSwipeTouchListener() {
public boolean onSwipeTop() {
Toast.makeText(MainActivity.this, "top", Toast.LENGTH_SHORT).show();
return true;
}
public boolean onSwipeRight() {
Toast.makeText(MainActivity.this, "right", Toast.LENGTH_SHORT).show();
return true;
}
public boolean onSwipeLeft() {
Toast.makeText(MainActivity.this, "left", Toast.LENGTH_SHORT).show();
return true;
}
public boolean onSwipeBottom() {
Toast.makeText(MainActivity.this, "bottom", Toast.LENGTH_SHORT).show();
return true;
}
});