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package org.libreoffice;
import android.content.Intent;
import android.os.Bundle;
import androidx.annotation.Nullable;
import androidx.core.view.GestureDetectorCompat;
import androidx.appcompat.app.AppCompatActivity;
import android.view.GestureDetector;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.webkit.WebView;
import android.widget.Button;
import android.widget.ImageButton;
public class PresentationActivity extends AppCompatActivity {
private static final String LOGTAG = PresentationActivity.class.getSimpleName();
WebView mWebView;
View mGestureView;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
View decorView = getWindow().getDecorView();
// Hide the status bar.
int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
setContentView(R.layout.presentation_mode);
// get intent and url
Intent intent = getIntent();
String filePath = intent.getDataString();
// set up WebView
mWebView = findViewById(R.id.presentation_view);
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
return true;
}
});
// set up buttons within presentation_gesture_view
ImageButton prevButton = findViewById(R.id.slide_show_nav_prev);
ImageButton nextButton = findViewById(R.id.slide_show_nav_next);
Button backButton = findViewById(R.id.slide_show_nav_back);
prevButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
pageLeft();
}
});
nextButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
pageRight();
}
});
backButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
onBackPressed();
}
});
// set up presentation_gesture_view
mGestureView = findViewById(R.id.presentation_gesture_view);
final GestureDetectorCompat gestureDetector =
new GestureDetectorCompat(this, new PresentationGestureViewListener());
mGestureView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
});
// load url
mWebView.loadUrl(filePath);
}
private class PresentationGestureViewListener extends GestureDetector.SimpleOnGestureListener {
private static final int SWIPE_VELOCITY_THRESHOLD = 100;
private static final int SCROLL_THRESHOLD = 10; // if scrollCounter is larger than this, a page switch is triggered
private int scrollCounter = 0; // a counter for measuring scrolling distance
@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(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (diffX > 0) {
pageRight();
} else {
pageLeft();
}
result = true;
}
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
boolean result = false;
try {
float diffY = e2.getY() - e1.getY();
float diffX = e2.getX() - e1.getX();
if (Math.abs(diffX) < Math.abs(diffY)) {
if (distanceY > 0) {
scrollCounter++;
if (scrollCounter >= SCROLL_THRESHOLD) {
pageRight();
scrollCounter = 0;
}
} else {
scrollCounter--;
if (scrollCounter <= -SCROLL_THRESHOLD) {
pageLeft();
scrollCounter = 0;
}
}
result = true;
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
if (e.getX() < mGestureView.getWidth()/3) {
pageLeft();
} else if (e.getX() < mGestureView.getWidth()*2/3) {
hideControlButtons();
} else {
pageRight();
}
return true;
}
}
private void hideControlButtons() {
View[] views= {findViewById(R.id.slide_show_nav_prev),findViewById(R.id.slide_show_nav_next),findViewById(R.id.slide_show_nav_back)} ;
for (View view : views) {
if (view.getVisibility() == View.GONE) {
view.setVisibility(View.VISIBLE);
} else if (view.getVisibility() == View.VISIBLE) {
view.setVisibility(View.GONE);
}
}
}
private void pageLeft() {
mWebView.dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_DPAD_LEFT));
}
private void pageRight() {
mWebView.dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_DPAD_RIGHT));
}
}
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