1 /*
2  * Copyright (C) 2013 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.example.android.toongame;
18 
19 import android.content.Context;
20 import android.graphics.Canvas;
21 import android.graphics.Matrix;
22 import android.graphics.RectF;
23 import android.util.AttributeSet;
24 import android.view.View;
25 import android.widget.TextView;
26 
27 /**
28  * This custom TextView can be skewed to the left or right to enable anticipation and
29  * follow-through effects
30  */
31 public class SkewableTextView extends TextView {
32 
33     private float mSkewX;
34     RectF mTempRect = new RectF();
35 
SkewableTextView(Context context, AttributeSet attrs, int defStyle)36     public SkewableTextView(Context context, AttributeSet attrs, int defStyle) {
37         super(context, attrs, defStyle);
38     }
39 
SkewableTextView(Context context, AttributeSet attrs)40     public SkewableTextView(Context context, AttributeSet attrs) {
41         super(context, attrs);
42     }
43 
SkewableTextView(Context context)44     public SkewableTextView(Context context) {
45         super(context);
46     }
47 
48     @Override
onDraw(Canvas canvas)49     protected void onDraw(Canvas canvas) {
50         if (mSkewX != 0) {
51             canvas.translate(0, getHeight());
52             canvas.skew(mSkewX, 0);
53             canvas.translate(0,  -getHeight());
54         }
55         super.onDraw(canvas);
56     }
57 
getSkewX()58     public float getSkewX() {
59         return mSkewX;
60     }
61 
setSkewX(float value)62     public void setSkewX(float value) {
63         if (value != mSkewX) {
64             mSkewX = value;
65             invalidate();             // force redraw with new skew value
66             invalidateSkewedBounds(); // also invalidate appropriate area of parent
67         }
68     }
69 
70     /**
71      * Need to invalidate proper area of parent for skewed bounds
72      */
invalidateSkewedBounds()73     private void invalidateSkewedBounds() {
74         if (mSkewX != 0) {
75             Matrix matrix = new Matrix();
76             matrix.setSkew(-mSkewX, 0);
77             mTempRect.set(0, 0, getRight(), getBottom());
78             matrix.mapRect(mTempRect);
79             mTempRect.offset(getLeft() + getTranslationX(), getTop() + getTranslationY());
80             ((View) getParent()).invalidate((int) mTempRect.left, (int) mTempRect.top,
81                     (int) (mTempRect.right +.5f), (int) (mTempRect.bottom + .5f));
82         }
83     }
84 }
85