Home | History | Annotate | Download | only in views 
      1 /*
      2  * Copyright (C) 2017 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.launcher3.views;
     18 
     19 import android.content.Context;
     20 import android.content.res.TypedArray;
     21 import android.graphics.Canvas;
     22 import android.graphics.Color;
     23 import android.support.v4.graphics.ColorUtils;
     24 import android.util.AttributeSet;
     25 import android.widget.TextView;
     26 
     27 import com.android.launcher3.BubbleTextView;
     28 import com.android.launcher3.R;
     29 
     30 /**
     31  * Extension of {@link BubbleTextView} which draws two shadows on the text (ambient and key shadows}
     32  */
     33 public class DoubleShadowBubbleTextView extends BubbleTextView {
     34 
     35     private final ShadowInfo mShadowInfo;
     36 
     37     public DoubleShadowBubbleTextView(Context context) {
     38         this(context, null);
     39     }
     40 
     41     public DoubleShadowBubbleTextView(Context context, AttributeSet attrs) {
     42         this(context, attrs, 0);
     43     }
     44 
     45     public DoubleShadowBubbleTextView(Context context, AttributeSet attrs, int defStyle) {
     46         super(context, attrs, defStyle);
     47         mShadowInfo = new ShadowInfo(context, attrs, defStyle);
     48         setShadowLayer(mShadowInfo.ambientShadowBlur, 0, 0, mShadowInfo.ambientShadowColor);
     49     }
     50 
     51     @Override
     52     public void onDraw(Canvas canvas) {
     53         // If text is transparent or shadow alpha is 0, don't draw any shadow
     54         if (mShadowInfo.skipDoubleShadow(this)) {
     55             super.onDraw(canvas);
     56             return;
     57         }
     58         int alpha = Color.alpha(getCurrentTextColor());
     59 
     60         // We enhance the shadow by drawing the shadow twice
     61         getPaint().setShadowLayer(mShadowInfo.ambientShadowBlur, 0, 0,
     62                 ColorUtils.setAlphaComponent(mShadowInfo.ambientShadowColor, alpha));
     63 
     64         drawWithoutBadge(canvas);
     65         canvas.save();
     66         canvas.clipRect(getScrollX(), getScrollY() + getExtendedPaddingTop(),
     67                 getScrollX() + getWidth(),
     68                 getScrollY() + getHeight());
     69 
     70         getPaint().setShadowLayer(mShadowInfo.keyShadowBlur, 0.0f, mShadowInfo.keyShadowOffset,
     71                 ColorUtils.setAlphaComponent(mShadowInfo.keyShadowColor, alpha));
     72         drawWithoutBadge(canvas);
     73         canvas.restore();
     74 
     75         drawBadgeIfNecessary(canvas);
     76     }
     77 
     78     public static class ShadowInfo {
     79         public final float ambientShadowBlur;
     80         public final int ambientShadowColor;
     81 
     82         public final float keyShadowBlur;
     83         public final float keyShadowOffset;
     84         public final int keyShadowColor;
     85 
     86         public ShadowInfo(Context c, AttributeSet attrs, int defStyle) {
     87 
     88             TypedArray a = c.obtainStyledAttributes(
     89                     attrs, R.styleable.ShadowInfo, defStyle, 0);
     90 
     91             ambientShadowBlur = a.getDimension(R.styleable.ShadowInfo_ambientShadowBlur, 0);
     92             ambientShadowColor = a.getColor(R.styleable.ShadowInfo_ambientShadowColor, 0);
     93 
     94             keyShadowBlur = a.getDimension(R.styleable.ShadowInfo_keyShadowBlur, 0);
     95             keyShadowOffset = a.getDimension(R.styleable.ShadowInfo_keyShadowOffset, 0);
     96             keyShadowColor = a.getColor(R.styleable.ShadowInfo_keyShadowColor, 0);
     97             a.recycle();
     98         }
     99 
    100         public boolean skipDoubleShadow(TextView textView) {
    101             int textAlpha = Color.alpha(textView.getCurrentTextColor());
    102             int keyShadowAlpha = Color.alpha(keyShadowColor);
    103             int ambientShadowAlpha = Color.alpha(ambientShadowColor);
    104             if (textAlpha == 0 || (keyShadowAlpha == 0 && ambientShadowAlpha == 0)) {
    105                 textView.getPaint().clearShadowLayer();
    106                 return true;
    107             } else if (ambientShadowAlpha > 0) {
    108                 textView.getPaint().setShadowLayer(ambientShadowBlur, 0, 0,
    109                         ColorUtils.setAlphaComponent(ambientShadowColor, textAlpha));
    110                 return true;
    111             } else if (keyShadowAlpha > 0) {
    112                 textView.getPaint().setShadowLayer(keyShadowBlur, 0.0f, keyShadowOffset,
    113                         ColorUtils.setAlphaComponent(keyShadowColor, textAlpha));
    114                 return true;
    115             } else {
    116                 return false;
    117             }
    118         }
    119     }
    120 }
    121