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
OnSwipeTouchListener.java:
import android.content.Context;
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() {
}
}
用法:
imageView.setOnTouchListener(new OnSwipeTouchListener(MyActivity.this) {
public void onSwipeTop() {
Toast.makeText(MyActivity.this, "top", Toast.LENGTH_SHORT).show();
}
public void onSwipeRight() {
Toast.makeText(MyActivity.this, "right", Toast.LENGTH_SHORT).show();
}
public void onSwipeLeft() {
Toast.makeText(MyActivity.this, "left", Toast.LENGTH_SHORT).show();
}
public void onSwipeBottom() {
Toast.makeText(MyActivity.this, "bottom", Toast.LENGTH_SHORT).show();
}
});
其他回答
import android.content.Context
import android.view.GestureDetector
import android.view.GestureDetector.SimpleOnGestureListener
import android.view.MotionEvent
import android.view.View
import android.view.View.OnTouchListener
/**
* Detects left and right swipes across a view.
*/
class OnSwipeTouchListener(context: Context, onSwipeCallBack: OnSwipeCallBack?) : OnTouchListener {
private var gestureDetector : GestureDetector
private var onSwipeCallBack: OnSwipeCallBack?=null
init {
gestureDetector = GestureDetector(context, GestureListener())
this.onSwipeCallBack = onSwipeCallBack!!
}
companion object {
private val SWIPE_DISTANCE_THRESHOLD = 100
private val SWIPE_VELOCITY_THRESHOLD = 100
}
/* fun onSwipeLeft() {}
fun onSwipeRight() {}*/
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(eve1: MotionEvent?, eve2: MotionEvent?, velocityX: Float, velocityY: Float): Boolean {
try {
if(eve1 != null&& eve2!= null) {
val distanceX = eve2?.x - eve1?.x
val distanceY = eve2?.y - eve1?.y
if (Math.abs(distanceX) > Math.abs(distanceY) && Math.abs(distanceX) > SWIPE_DISTANCE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (distanceX > 0)
onSwipeCallBack!!.onSwipeLeftCallback()
else
onSwipeCallBack!!.onSwipeRightCallback()
return true
}
}
}catch (exception:Exception){
exception.printStackTrace()
}
return false
}
}
}
这是一个简单的Android代码,用于检测手势方向
在MainActivity.java和activity_main.xml中编写如下代码:
MainActivity.java
import java.util.ArrayList;
import android.app.Activity;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.gesture.GestureStroke;
import android.gesture.Prediction;
import android.os.Bundle;
import android.widget.Toast;
public class MainActivity extends Activity implements
OnGesturePerformedListener {
GestureOverlayView gesture;
GestureLibrary lib;
ArrayList<Prediction> prediction;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lib = GestureLibraries.fromRawResource(MainActivity.this,
R.id.gestureOverlayView1);
gesture = (GestureOverlayView) findViewById(R.id.gestureOverlayView1);
gesture.addOnGesturePerformedListener(this);
}
@Override
public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
ArrayList<GestureStroke> strokeList = gesture.getStrokes();
// prediction = lib.recognize(gesture);
float f[] = strokeList.get(0).points;
String str = "";
if (f[0] < f[f.length - 2]) {
str = "Right gesture";
} else if (f[0] > f[f.length - 2]) {
str = "Left gesture";
} else {
str = "no direction";
}
Toast.makeText(getApplicationContext(), str, Toast.LENGTH_LONG).show();
}
}
activity_main.xml
<android.gesture.GestureOverlayView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:android1="http://schemas.android.com/apk/res/android"
xmlns:android2="http://schemas.android.com/apk/res/android"
android:id="@+id/gestureOverlayView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android1:orientation="vertical" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Draw gesture"
android:textAppearance="?android:attr/textAppearanceMedium" />
</android.gesture.GestureOverlayView>
为了添加一个onClick,下面是我所做的。
....
// in OnSwipeTouchListener class
private final class GestureListener extends SimpleOnGestureListener {
.... // normal GestureListener code
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
onClick(); // my method
return super.onSingleTapConfirmed(e);
}
} // end GestureListener class
public void onSwipeRight() {
}
public void onSwipeLeft() {
}
public void onSwipeTop() {
}
public void onSwipeBottom() {
}
public void onClick(){
}
// as normal
@Override
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
} // end OnSwipeTouchListener class
我正在使用Fragments,因此使用getActivity()作为上下文。这就是我实现它的方法——而且它很有效。
myLayout.setOnTouchListener(new OnSwipeTouchListener(getActivity()) {
public void onSwipeTop() {
Toast.makeText(getActivity(), "top", Toast.LENGTH_SHORT).show();
}
public void onSwipeRight() {
Toast.makeText(getActivity(), "right", Toast.LENGTH_SHORT).show();
}
public void onSwipeLeft() {
Toast.makeText(getActivity(), "left", Toast.LENGTH_SHORT).show();
}
public void onSwipeBottom() {
Toast.makeText(getActivity(), "bottom", Toast.LENGTH_SHORT).show();
}
public void onClick(){
Toast.makeText(getActivity(), "clicked", Toast.LENGTH_SHORT).show();
}
});
我一直在做类似的事情,但仅限于水平滑动
import android.content.Context
import android.view.GestureDetector
import android.view.MotionEvent
import android.view.View
abstract class OnHorizontalSwipeListener(val context: Context) : View.OnTouchListener {
companion object {
const val SWIPE_MIN = 50
const val SWIPE_VELOCITY_MIN = 100
}
private val detector = GestureDetector(context, GestureListener())
override fun onTouch(view: View, event: MotionEvent) = detector.onTouchEvent(event)
abstract fun onRightSwipe()
abstract fun onLeftSwipe()
private inner class GestureListener : GestureDetector.SimpleOnGestureListener() {
override fun onDown(e: MotionEvent) = true
override fun onFling(e1: MotionEvent, e2: MotionEvent, velocityX: Float, velocityY: Float)
: Boolean {
val deltaY = e2.y - e1.y
val deltaX = e2.x - e1.x
if (Math.abs(deltaX) < Math.abs(deltaY)) return false
if (Math.abs(deltaX) < SWIPE_MIN
&& Math.abs(velocityX) < SWIPE_VELOCITY_MIN) return false
if (deltaX > 0) onRightSwipe() else onLeftSwipe()
return true
}
}
}
然后它可以用于视图组件
private fun listenHorizontalSwipe(view: View) {
view.setOnTouchListener(object : OnHorizontalSwipeListener(context!!) {
override fun onRightSwipe() {
Log.d(TAG, "Swipe right")
}
override fun onLeftSwipe() {
Log.d(TAG, "Swipe left")
}
}
)
}
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);