1 /*
2  * Copyright (C) 2016 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.setupwizardlib.view;
18 
19 import android.content.Context;
20 import android.graphics.drawable.Drawable;
21 import android.os.Build.VERSION;
22 import android.os.Build.VERSION_CODES;
23 import android.support.v4.view.ViewCompat;
24 import android.text.Annotation;
25 import android.text.SpannableString;
26 import android.text.Spanned;
27 import android.text.method.LinkMovementMethod;
28 import android.text.style.ClickableSpan;
29 import android.text.style.TextAppearanceSpan;
30 import android.util.AttributeSet;
31 import android.util.Log;
32 import android.view.MotionEvent;
33 import android.widget.TextView;
34 
35 import com.android.setupwizardlib.span.LinkSpan;
36 import com.android.setupwizardlib.span.SpanHelper;
37 import com.android.setupwizardlib.util.LinkAccessibilityHelper;
38 
39 /**
40  * An extension of TextView that automatically replaces the annotation tags as specified in
41  * {@link SpanHelper#replaceSpan(android.text.Spannable, Object, Object)}
42  */
43 public class RichTextView extends TextView {
44 
45     /* static section */
46 
47     private static final String TAG = "RichTextView";
48 
49     private static final String ANNOTATION_LINK = "link";
50     private static final String ANNOTATION_TEXT_APPEARANCE = "textAppearance";
51 
52     /**
53      * Replace <annotation> tags in strings to become their respective types. Currently 2
54      * types are supported:
55      * <ol>
56      *     <li>&lt;annotation link="foobar"&gt; will create a
57      *     {@link com.android.setupwizardlib.span.LinkSpan} that broadcasts with the key
58      *     "foobar"</li>
59      *     <li>&lt;annotation textAppearance="TextAppearance.FooBar"&gt; will create a
60      *     {@link android.text.style.TextAppearanceSpan} with @style/TextAppearance.FooBar</li>
61      * </ol>
62      */
getRichText(Context context, CharSequence text)63     public static CharSequence getRichText(Context context, CharSequence text) {
64         if (text instanceof Spanned) {
65             final SpannableString spannable = new SpannableString(text);
66             final Annotation[] spans = spannable.getSpans(0, spannable.length(), Annotation.class);
67             for (Annotation span : spans) {
68                 final String key = span.getKey();
69                 if (ANNOTATION_TEXT_APPEARANCE.equals(key)) {
70                     String textAppearance = span.getValue();
71                     final int style = context.getResources()
72                             .getIdentifier(textAppearance, "style", context.getPackageName());
73                     if (style == 0) {
74                         Log.w(TAG, "Cannot find resource: " + style);
75                     }
76                     final TextAppearanceSpan textAppearanceSpan =
77                             new TextAppearanceSpan(context, style);
78                     SpanHelper.replaceSpan(spannable, span, textAppearanceSpan);
79                 } else if (ANNOTATION_LINK.equals(key)) {
80                     LinkSpan link = new LinkSpan(span.getValue());
81                     SpanHelper.replaceSpan(spannable, span, link);
82                 }
83             }
84             return spannable;
85         }
86         return text;
87     }
88 
89     /* non-static section */
90 
91     private LinkAccessibilityHelper mAccessibilityHelper;
92 
RichTextView(Context context)93     public RichTextView(Context context) {
94         super(context);
95         init();
96     }
97 
RichTextView(Context context, AttributeSet attrs)98     public RichTextView(Context context, AttributeSet attrs) {
99         super(context, attrs);
100         init();
101     }
102 
init()103     private void init() {
104         mAccessibilityHelper = new LinkAccessibilityHelper(this);
105         ViewCompat.setAccessibilityDelegate(this, mAccessibilityHelper);
106     }
107 
108     @Override
setText(CharSequence text, BufferType type)109     public void setText(CharSequence text, BufferType type) {
110         text = getRichText(getContext(), text);
111         // Set text first before doing anything else because setMovementMethod internally calls
112         // setText. This in turn ends up calling this method with mText as the first parameter
113         super.setText(text, type);
114         boolean hasLinks = hasLinks(text);
115 
116         if (hasLinks) {
117             // When a TextView has a movement method, it will set the view to clickable. This makes
118             // View.onTouchEvent always return true and consumes the touch event, essentially
119             // nullifying any return values of MovementMethod.onTouchEvent.
120             // To still allow propagating touch events to the parent when this view doesn't have
121             // links, we only set the movement method here if the text contains links.
122             setMovementMethod(LinkMovementMethod.getInstance());
123         } else {
124             setMovementMethod(null);
125         }
126         // ExploreByTouchHelper automatically enables focus for RichTextView
127         // even though it may not have any links. Causes problems during talkback
128         // as individual TextViews consume touch events and thereby reducing the focus window
129         // shown by Talkback. Disable focus if there are no links
130         setFocusable(hasLinks);
131     }
132 
hasLinks(CharSequence text)133     private boolean hasLinks(CharSequence text) {
134         if (text instanceof Spanned) {
135             final ClickableSpan[] spans =
136                     ((Spanned) text).getSpans(0, text.length(), ClickableSpan.class);
137             return spans.length > 0;
138         }
139         return false;
140     }
141 
142     @Override
dispatchHoverEvent(MotionEvent event)143     protected boolean dispatchHoverEvent(MotionEvent event) {
144         if (mAccessibilityHelper != null && mAccessibilityHelper.dispatchHoverEvent(event)) {
145             return true;
146         }
147         return super.dispatchHoverEvent(event);
148     }
149 
150     @Override
drawableStateChanged()151     protected void drawableStateChanged() {
152         super.drawableStateChanged();
153 
154         if (VERSION.SDK_INT >= VERSION_CODES.JELLY_BEAN_MR1) {
155             // b/26765507 causes drawableStart and drawableEnd to not get the right state on M. As a
156             // workaround, set the state on those drawables directly.
157             final int[] state = getDrawableState();
158             for (Drawable drawable : getCompoundDrawablesRelative()) {
159                 if (drawable != null) {
160                     if (drawable.setState(state)) {
161                         invalidateDrawable(drawable);
162                     }
163                 }
164             }
165         }
166     }
167 }
168