tt-rss-android/src/org/fox/ttrss/TitleWebView.java
2013-04-21 17:01:26 +04:00

91 lines
2.7 KiB
Java

package org.fox.ttrss;
// http://www.techques.com/question/1-9718245/Webview-in-Scrollview
import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.webkit.WebView;
public class TitleWebView extends WebView{
public TitleWebView(Context context, AttributeSet attrs){
super(context, attrs);
}
private int titleHeight;
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
// determine height of title bar
View title = getChildAt(0);
titleHeight = title==null ? 0 : title.getMeasuredHeight();
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev){
return true; // don't pass our touch events to children (title bar), we send these in dispatchTouchEvent
}
private boolean touchInTitleBar;
@Override
public boolean dispatchTouchEvent(MotionEvent me){
boolean wasInTitle = false;
switch(me.getActionMasked()){
case MotionEvent.ACTION_DOWN:
touchInTitleBar = (me.getY() <= visibleTitleHeight());
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
wasInTitle = touchInTitleBar;
touchInTitleBar = false;
break;
}
if(touchInTitleBar || wasInTitle) {
View title = getChildAt(0);
if(title!=null) {
// this touch belongs to title bar, dispatch it here
me.offsetLocation(0, getScrollY());
return title.dispatchTouchEvent(me);
}
}
// this is our touch, offset and process
me.offsetLocation(0, -titleHeight);
return super.dispatchTouchEvent(me);
}
/**
* @return visible height of title (may return negative values)
*/
private int visibleTitleHeight(){
return titleHeight-getScrollY();
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt){
super.onScrollChanged(l, t, oldl, oldt);
View title = getChildAt(0);
if(title!=null) // undo horizontal scroll, so that title scrolls only vertically
title.offsetLeftAndRight(l - title.getLeft());
}
@Override
protected void onDraw(Canvas c){
c.save();
int tH = visibleTitleHeight();
if(tH>0) {
// clip so that it doesn't clear background under title bar
int sx = getScrollX(), sy = getScrollY();
c.clipRect(sx, sy+tH, sx+getWidth(), sy+getHeight());
}
c.translate(0, titleHeight);
super.onDraw(c);
c.restore();
}
}