我正在开发一个内置RelativeLayout和WebView的简单Android应用程序。
我必须检测从底部到顶部的滑动仅在屏幕左侧的20％处完成。因此，当用户从下到上在该空间中滑动时，我必须显示自定义对话框。
我尝试的是：
import android.app.Activity;
import android.view.MotionEvent;
import android.view.View;
public class ActivitySwipeDetector implements View.OnTouchListener {
static final String logTag = "ActivitySwipeDetector";
private Activity activity;
static final int MIN_DISTANCE = 100;
private float downY, upY;
public ActivitySwipeDetector(Activity activity){
this.activity = activity;
}
public void onRightToLeftSwipe(){
}
public void onLeftToRightSwipe(){
}
public void onTopToBottomSwipe(){
}
public void onBottomToTopSwipe(){
System.out.println("BOTTOM TO TOP SWIPE DONE!");
}
public boolean onTouch(View v, MotionEvent event) {
switch(event.getAction()){
case MotionEvent.ACTION_DOWN: {
downY = event.getY();
return true;
}
case MotionEvent.ACTION_UP: {
upY = event.getY();
float deltaY = downY - upY;
if(Math.abs(deltaY) > MIN_DISTANCE){
if(deltaY > 0) { this.onBottomToTopSwipe(); return true; }
}
else {
return false;
}
return true;
}
}
return false;
}
}
layout = (RelativeLayout)this.findViewById(R.id.layout);
layout.setOnTouchListener(activitySwipeDetector);
但它什么都不做！
所以我尝试以这种方式创建自定义webview：
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.webkit.WebView;
public class MyWebView extends WebView {
public MyWebView(Context context) {
super(context);
}
public MyWebView(Context context,AttributeSet set){
super(context,set);
}
@Override
public boolean onTouchEvent(MotionEvent evt) {
boolean consumed = super.onTouchEvent(evt);
if (isClickable()) {
switch (evt.getAction()) {
case MotionEvent.ACTION_DOWN:
lastTouchY = evt.getY();
downTime = evt.getEventTime();
hasMoved = false;
break;
case MotionEvent.ACTION_MOVE:
hasMoved = moved(evt);
break;
case MotionEvent.ACTION_UP:
float actualTouchY = evt.getY();
long currentTime = evt.getEventTime();
float difference = Math.abs(lastTouchY - actualTouchY);
long time = currentTime - downTime;
if ( (lastTouchY < actualTouchY) && (time < 220) && (difference > 100) ) {
System.out.println("SWIPE1");
}
if ( (lastTouchY > actualTouchY) && (time < 220) && (difference > 100) ) {
System.out.println("SWIPE2");
}
break;
}
}
return consumed || isClickable();
}
long downTime;
private float lastTouchY;
private boolean hasMoved = false;
private boolean moved(MotionEvent evt) {
return hasMoved ||
Math.abs(evt.getY() - lastTouchY) > 10.0;
}
}
但没有成功！有人能帮我吗？？谢谢！！！！！ ：）
答案 0 :(得分：38)
将GestureDetector与自定义网络视图一起使用..
webView.setGestureDetector(new GestureDetector(new CustomeGestureDetector()));
手势检测器：
private class CustomeGestureDetector extends SimpleOnGestureListener {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
if(e1 == null || e2 == null) return false;
if(e1.getPointerCount() > 1 || e2.getPointerCount() > 1) return false;
else {
try { // right to left swipe .. go to next page
if(e1.getX() - e2.getX() > 100 && Math.abs(velocityX) > 800) {
//do your stuff
return true;
} //left to right swipe .. go to prev page
else if (e2.getX() - e1.getX() > 100 && Math.abs(velocityX) > 800) {
//do your stuff
return true;
} //bottom to top, go to next document
else if(e1.getY() - e2.getY() > 100 && Math.abs(velocityY) > 800
&& webView.getScrollY() >= webView.getScale() * (webView.getContentHeight() - webView.getHeight())) {
//do your stuff
return true;
} //top to bottom, go to prev document
else if (e2.getY() - e1.getY() > 100 && Math.abs(velocityY) > 800 ) {
//do your stuff
return true;
}
} catch (Exception e) { // nothing
}
return false;
}
}
}
自定义网络视图：
public final class CustomWebView extends WebView {
private GestureDetector gestureDetector;
/**
* @param context
* @param attrs
* @param defStyle
*/
public CustomWebView(Context context) {
super(context);
}
/**
* @param context
* @param attrs
* @param defStyle
*/
public CustomWebView(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* @param context
* @param attrs
* @param defStyle
*/
public CustomWebView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
/*
* @see android.webkit.WebView#onScrollChanged(int, int, int, int)
*/
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
super.onScrollChanged(l, t, oldl, oldt);
}
/*
* @see android.webkit.WebView#onTouchEvent(android.view.MotionEvent)
*/
@Override
public boolean onTouchEvent(MotionEvent ev) {
return gestureDetector.onTouchEvent(ev) || super.onTouchEvent(ev);
}
public void setGestureDetector(GestureDetector gestureDetector) {
this.gestureDetector = gestureDetector;
}
}
如АндрейМосквичёв所述：
通过注册触摸侦听器：webview.setOnTouchListener(new OnTouchListener() ...)并从中调用gestureDetector.onTouchEvent(ev)，可以在不派生WebView类的情况下解决它。
答案 1 :(得分：0)
不推荐使用'webView.setGestureDetector（new GestureDetector（'）解决方案。
下一个解决方案易于实现。滚动，单击链接仍然有效。
1-将此添加到您的webView：
public class OnSwipeWebviewTouchListener implements View.OnTouchListener {
private final GestureDetector gestureDetector;
public OnSwipeWebviewTouchListener(Context ctx, TouchListener touchListener) {
gestureDetector = new GestureDetector(ctx, new GestureListener(touchListener));
}
@Override
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
private TouchListener touchListener;
GestureListener(TouchListener touchListener) {
super();
this.touchListener = touchListener;
}
@Override
public boolean onDown(MotionEvent e) {
return false; // THIS does the trick
}
@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)) {
// You can customize these settings, so 30 is an example
if (Math.abs(diffX) > 30 && Math.abs(velocityX) > 30) {
if (diffX > 0) {
touchListener.onSwipeRight();
} else {
touchListener.onSwipeLeft();
}
result = true;
}
} else {
result = false;
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}
}
'this'意味着您让您的调用类实现了TouchListener接口方法。您可以通过onSwipeRight（）和onSwipeLeft（）方法实现导航。
2-使用此OnTouchListener：
public interface TouchListener {
default void onSwipeLeft() {
Logger.d( "Swipe left");
}
default void onSwipeRight() {
Logger.d( "Swipe right");
}
}
3-TouchListner的示例可能是：
{{1}}