你有两个选择
选项一
通过为 Web 视图上的触摸事件创建自定义侦听器。
我已经修改了@fernandohur对此问题的回答中的片段post https://stackoverflow.com/questions/13095494/how-to-detect-swipe-direction-between-left-right-and-up-down#26387629以匹配您的场景。
创建一个新类（OnSwipeListener.java）
import android.view.GestureDetector;
import android.view.MotionEvent;
public class OnSwipeListener extends GestureDetector.SimpleOnGestureListener {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
// Grab two events located on the plane at e1=(x1, y1) and e2=(x2, y2)
// Let e1 be the initial event
// e2 can be located at 4 different positions, consider the following diagram
// (Assume that lines are separated by 90 degrees.)
//
//
// \ A /
// \ /
// D e1 B
// / \
// / C \
//
// So if (x2,y2) falls in region:
// A => it's an UP swipe
// B => it's a RIGHT swipe
// C => it's a DOWN swipe
// D => it's a LEFT swipe
//
float x1 = e1.getX();
float y1 = e1.getY();
float x2 = e2.getX();
float y2 = e2.getY();
Direction direction = getDirection(x1,y1,x2,y2);
return onSwipe(direction, velocityX, velocityY);
}
/** Override this method. The Direction enum will tell you how the user swiped. */
public boolean onSwipe(Direction direction, float velocityX, float velocityY){
return false;
}
/**
* Given two points in the plane p1=(x1, x2) and p2=(y1, y1), this method
* returns the direction that an arrow pointing from p1 to p2 would have.
* @param x1 the x position of the first point
* @param y1 the y position of the first point
* @param x2 the x position of the second point
* @param y2 the y position of the second point
* @return the direction
*/
public Direction getDirection(float x1, float y1, float x2, float y2){
double angle = getAngle(x1, y1, x2, y2);
return Direction.fromAngle(angle);
}
/**
*
* Finds the angle between two points in the plane (x1,y1) and (x2, y2)
* The angle is measured with 0/360 being the X-axis to the right, angles
* increase counter clockwise.
*
* @param x1 the x position of the first point
* @param y1 the y position of the first point
* @param x2 the x position of the second point
* @param y2 the y position of the second point
* @return the angle between two points
*/
public double getAngle(float x1, float y1, float x2, float y2) {
double rad = Math.atan2(y1-y2,x2-x1) + Math.PI;
return (rad*180/Math.PI + 180)%360;
}
public enum Direction{
up,
down,
left,
right;
/**
* Returns a direction given an angle.
* Directions are defined as follows:
*
* Up: [45, 135]
* Right: [0,45] and [315, 360]
* Down: [225, 315]
* Left: [135, 225]
*
* @param angle an angle from 0 to 360 - e
* @return the direction of an angle
*/
public static Direction fromAngle(double angle){
if(inRange(angle, 45, 135)){
return Direction.up;
}
else if(inRange(angle, 0,45) || inRange(angle, 315, 360)){
return Direction.right;
}
else if(inRange(angle, 225, 315)){
return Direction.down;
}
else{
return Direction.left;
}
}
/**
* @param angle an angle
* @param init the initial bound
* @param end the final bound
* @return returns true if the given angle is in the interval [init, end).
*/
private static boolean inRange(double angle, float init, float end){
return (angle >= init) && (angle < end);
}
}
}
然后在您的活动中使用...
public class FullscreenActivity extends AppCompatActivity implements View.OnTouchListener {
private WebView blizzView;
private Button backButton;
private String website;
private GestureDetector gestureDetector;
/**
* Whether or not the system UI should be auto-hidden after
* {@link #AUTO_HIDE_DELAY_MILLIS} milliseconds.
*/
private static final boolean AUTO_HIDE = true;
/**
* If {@link #AUTO_HIDE} is set, the number of milliseconds to wait after
* user interaction before hiding the system UI.
*/
private static final int AUTO_HIDE_DELAY_MILLIS = 3000;
/**
* Some older devices needs a small delay between UI widget updates
* and a change of the status and navigation bar.
*/
private static final int UI_ANIMATION_DELAY = 300;
private final Handler mHideHandler = new Handler();
private final Runnable mHidePart2Runnable = new Runnable()
{
@SuppressLint("InlinedApi")
@Override
public void run() {
}
};
private final Runnable mShowPart2Runnable = new Runnable()
{
@Override
public void run() {
// Delayed display of UI elements
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.show();
}
}
};
private boolean mVisible;
private final Runnable mHideRunnable = new Runnable() {
@Override
public void run() {
hide();
}
};
@Override
public boolean onTouch(View v, MotionEvent event) {
Log.d("SWIPER", "onTouch: ");
gestureDetector.onTouchEvent(event);
return false;
}
public void scrollUpwards(int scroll_speed) {
try{
ObjectAnimator anim = ObjectAnimator.ofInt(blizzView, "scrollY", blizzView.getScrollY(), blizzView.getScrollY() - scroll_speed);
anim.setDuration(800).start();
}catch (Exception ex){}
}
public void scrollDownwards(int scroll_speed) {
try{
// float maxScrollY = blizzView.getContentHeight() * blizzView.getScale() - blizzView.getMeasuredHeight();
if(blizzView.getScrollY() <= 100){
//due to the scroll animation the web page slows down at the top
//hence we add some extra speed when user is at the top of page to prevent from
//experiencing delay when scrolling back down
scroll_speed += 1300;
}
ObjectAnimator anim = ObjectAnimator.ofInt(blizzView, "scrollY", blizzView.getScrollY(), blizzView.getScrollY() + scroll_speed);
anim.setDuration(800).start();
}catch (Exception ex){}
}
@SuppressLint("ClickableViewAccessibility")
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gestureDetector=new GestureDetector(this,new OnSwipeListener(){
@Override
public boolean onSwipe(Direction direction, float velocityX, float velocityY) {
// int scroll_jump_percentage = 60 / 100; //percent of velocity: increase(60) for faster scroll jump
int scroll_speed = ((int) Math.abs(velocityY)) * 60 / 100; //percent of velocity: increase(60) for faster scroll jump;
if (direction==Direction.up){
//do your stuff
// Log.d("SWIPER", "onSwipe: up");
scrollDownwards(scroll_speed);
Toast.makeText(getApplicationContext(),"You swiped UP ("+scroll_speed+")",Toast.LENGTH_SHORT).show();
//we made it!
return true;
}
else if (direction==Direction.down){
//do your stuff
// Log.d("SWIPER", "onSwipe: down");
scrollUpwards(scroll_speed);
Toast.makeText(getApplicationContext(),"You swiped DOWN ("+scroll_speed+")",Toast.LENGTH_SHORT).show();
//we made it!
return true;
}
//nothing to handle here... Mr. WebView can do the rest
return false;
}
});
mVisible = true;
website = "https://www.blizz-z.de";
blizzView = findViewById(R.id.blizzView);
blizzView.setOnTouchListener(this);
WebSettings settings = blizzView.getSettings();
settings.setJavaScriptEnabled(true);
settings.setBuiltInZoomControls(false);
// https://developer.android.com/reference/android/webkit/WebViewClient
blizzView.setWebViewClient(new WebViewClient() {
@Override
public void onReceivedHttpError(WebView view, WebResourceRequest request, WebResourceResponse errorResponse) {
super.onReceivedHttpError(view, request, errorResponse);
// Log.i("debug_log", errorResponse.getReasonPhrase());
}
@Override
public void onReceivedHttpAuthRequest(WebView view, HttpAuthHandler handler, String host, String realm)
{
super.onReceivedHttpAuthRequest(view, handler, host, realm);
view.setHttpAuthUsernamePassword(host, realm, "macs", "20macs14");
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon)
{
// check here the url
if (url.endsWith(".pdf")) {
Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(browserIntent);
} else {
super.onPageStarted(view, url, favicon);
}
}
@Override
// Notify the host application that a page has finished loading.
public void onPageFinished(WebView view, String url)
{
super.onPageFinished(view, url);
// Hide/Show back button
backButton = findViewById(R.id.backButton);
backButton.setEnabled(blizzView.canGoBack());
if (blizzView.canGoBack()) {
backButton.setVisibility(View.VISIBLE);
} else {
backButton.setVisibility(View.INVISIBLE);
}
js(blizzView, "jQuery(document).ready(function() {"
+ "setInterval(function() {"
+ "jQuery('#myInput').css('background', '#'+(Math.random()*0xFFFFFF<<0).toString(16));"
+ "jQuery('a').each(function() {"
+ "jQuery(this).removeAttr('download');"
+ "});"
+ "}, 1000);"
+ "});");
//inject script (this script would remove all event listener from product image
// that was placed by your MagicZoom Js Library
//TEMP FIX
/* blizzView.loadUrl(
"javascript:(function() { " +
"var slides = document.getElementsByClassName(\"MagicZoom\");\n" +
"for(var i = 0; i < slides.length; i++)\n" +
"{\n" +
"var old_element = slides.item(i);\n" +
"old_element.href = '#';\n" +
" var new_element = old_element.cloneNode(true);\n" +
"\t\t\t\told_element.parentNode.replaceChild(new_element, old_element);\n" +
" \n" +
" }" +
"})()");*/
}
// Give the host application a chance to take control when a URL is about to be loaded in the current WebView.
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url)
{
Log.i("debug_log", "shouldOverrideUrlLoading");
//view.loadDataWithBaseURL("https://www.blizz-z.de", );
// Allow download of .pdf files
if (url.endsWith(".pdf")) {
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
// if want to download pdf manually create AsyncTask here
// and download file
return true;
}
// Also allow urls not starting with http or https (e.g. tel, mailto, ...)
if( URLUtil.isNetworkUrl(url) ) {
return false;
} else {
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
}
return true;
}
});
// URL laden:
blizzView.loadUrl(website);
}
@Override
protected void onPostCreate(Bundle savedInstanceState)
{
Log.i("debug_log", "onPostCreate");
super.onPostCreate(savedInstanceState);
// Trigger the initial hide() shortly after the activity has been
// created, to briefly hint to the user that UI controls
// are available.
delayedHide(100);
}
private void toggle()
{
if (mVisible) {
hide();
} else {
show();
}
}
private void hide()
{
// Hide UI first
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.hide();
}
mVisible = false;
// Schedule a runnable to remove the status and navigation bar after a delay
mHideHandler.removeCallbacks(mShowPart2Runnable);
mHideHandler.postDelayed(mHidePart2Runnable, UI_ANIMATION_DELAY);
}
@SuppressLint("InlinedApi")
private void show()
{
// Show the system bar
mVisible = true;
// Schedule a runnable to display UI elements after a delay
mHideHandler.removeCallbacks(mHidePart2Runnable);
mHideHandler.postDelayed(mShowPart2Runnable, UI_ANIMATION_DELAY);
}
/**
* Schedules a call to hide() in delay milliseconds, canceling any
* previously scheduled calls.
*/
private void delayedHide(int delayMillis)
{
mHideHandler.removeCallbacks(mHideRunnable);
mHideHandler.postDelayed(mHideRunnable, delayMillis);
}
public void js(WebView view, String code)
{
String javascriptCode = "javascript:" + code;
if (Build.VERSION.SDK_INT >= 19) {
view.evaluateJavascript(javascriptCode, new ValueCallback<String>() {
@Override
public void onReceiveValue(String response) {
Log.i("debug_log", response);
}
});
} else {
view.loadUrl(javascriptCode);
}
}
// Event Listener ------------------------------------------------------------------------------
public void goBack(android.view.View view)
{
blizzView.goBack();
}
// If back button of smartphone is pressed, then go back in browser history
@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
Log.i("debug_log", "KeyDown");
if (event.getAction() == KeyEvent.ACTION_DOWN) {
switch (keyCode) {
case KeyEvent.KEYCODE_BACK:
if (blizzView.canGoBack())
blizzView.goBack();
else
finish();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
}
选项二
将以下块添加到页面完成WebviewClient 的方法
//This will remove all javascript event listener from affected images. (offending script: MagicZoomPlus.js)
//Setback of this is that images would no longer zoom in when clicked.
blizzView.loadUrl(
"javascript:(function() { " +
"var slides = document.getElementsByClassName(\"MagicZoom\");\n" +
"for(var i = 0; i < slides.length; i++)\n" +
"{\n" +
"var old_element = slides.item(i);\n" +
"old_element.href = '#';\n" +
" var new_element = old_element.cloneNode(true);\n" +
"\t\t\t\told_element.parentNode.replaceChild(new_element, old_element);\n" +
" \n" +
" }" +
"})()");
