MyTextView.java

package com.ch_linghu.fanfoudroid.ui.module;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.graphics.Color;
import android.text.Layout;
import android.text.Spannable;
import android.text.Spanned;
import android.text.style.ForegroundColorSpan;
import android.text.style.URLSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.TextView;

import com.ch_linghu.fanfoudroid.R;
import com.ch_linghu.fanfoudroid.AppParam;
import com.ch_linghu.fanfoudroid.app.Preferences;

public class MyTextView extends TextView {
	private static float mFontSize = 15;
	private static boolean mFontSizeChanged = true;

	public MyTextView(Context context) {
		super(context, null);
	}

	public MyTextView(Context context, AttributeSet attrs) {
		super(context, attrs);

		setLinksClickable(false);

		Resources res = getResources();
		int color = res.getColor(R.color.link_color);
		setLinkTextColor(color);

		initFontSize();
	}

	public void initFontSize() {
		if (mFontSizeChanged) {
			mFontSize = getFontSizeFromPreferences(mFontSize);
			setFontSizeChanged(false); // reset
		}
		setTextSize(mFontSize);
	}

	private float getFontSizeFromPreferences(float defaultValue) {
		SharedPreferences preferences = AppParam.mPref;
		if (preferences.contains(Preferences.UI_FONT_SIZE)) {
			Log.v("DEBUG",
					preferences.getString(Preferences.UI_FONT_SIZE, "null")
							+ " CHANGE FONT SIZE");
			return Float.parseFloat(preferences.getString(
					Preferences.UI_FONT_SIZE, "14"));
		}
		return defaultValue;
	}

	private URLSpan mCurrentLink;
	private ForegroundColorSpan mLinkFocusStyle = new ForegroundColorSpan(
			Color.RED);

	@Override
	public boolean onTouchEvent(MotionEvent event) {
		CharSequence text = getText();
		int action = event.getAction();

		if (!(text instanceof Spannable)) {
			return super.onTouchEvent(event);
		}

		Spannable buffer = (Spannable) text;

		if (action == MotionEvent.ACTION_UP
				|| action == MotionEvent.ACTION_DOWN
				|| action == MotionEvent.ACTION_MOVE) {
			TextView widget = this;

			int x = (int) event.getX();
			int y = (int) event.getY();

			x -= widget.getTotalPaddingLeft();
			y -= widget.getTotalPaddingTop();

			x += widget.getScrollX();
			y += widget.getScrollY();

			Layout layout = widget.getLayout();
			int line = layout.getLineForVertical(y);
			int off = layout.getOffsetForHorizontal(line, x);

			URLSpan[] link = buffer.getSpans(off, off, URLSpan.class);

			if (link.length != 0) {
				if (action == MotionEvent.ACTION_UP) {
					if (mCurrentLink == link[0]) {
						link[0].onClick(widget);
					}
					mCurrentLink = null;
					buffer.removeSpan(mLinkFocusStyle);
				} else if (action == MotionEvent.ACTION_DOWN) {
					mCurrentLink = link[0];
					buffer.setSpan(mLinkFocusStyle,
							buffer.getSpanStart(link[0]),
							buffer.getSpanEnd(link[0]),
							Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
				}

				return true;
			}
		}

		mCurrentLink = null;
		buffer.removeSpan(mLinkFocusStyle);

		return super.onTouchEvent(event);
	}

	public static void setFontSizeChanged(boolean isChanged) {
		mFontSizeChanged = isChanged;
	}

	@Override
	public void onWindowFocusChanged(boolean hasWindowFocus) {
		super.onWindowFocusChanged(hasWindowFocus);
	}
}