AppBarLayout.OnOffsetChangedListenerµÄʹÓÃ

Èç¹ûûÌý˵¹ýAppBarLayout.OnOffsetChangedListener，ÄÇô¾ÍÏÈ¿´ÕâÀï：
http://www.jcodecraeer.com/a/anzhuokaifa/androidkaifa/2015/0616/3052.html

ÎÒÔÚÏîÄ¿ÖеÄʹÓÃ：

Java´úÂë

1. import android.content.Context;
2. import android.content.res.Resources;
3. import android.content.res.TypedArray;
4. import android.support.annotation.NonNull;
5. import android.support.design.widget.AppBarLayout;
6. import android.support.v7.widget.Toolbar;
7. import android.util.AttributeSet;
8. import android.util.TypedValue;
9. import android.view.View;
10. import android.view.ViewGroup;
11. import android.view.ViewParent;
12. import android.widget.LinearLayout;
13. import android.widget.TextView;
15. /**
16. * CollapsingAvatarToolbar±ØÐëÔÚAppBarLayoutÀïÃæ，±»CollapsingToolbarLayout°ü¹ü¡£
17. CollapsingAvatarToolbar±ØÐëÓиöToolbar°éËæ，Èç¹ûÄã²»ÏëʹÓÃToolbar，ÎÒÃÇ¿ÉÒÔÌÖÂÛÌÖÂÛ¡£
18. À©Õ¹¸ß¶È（Expanded height） È¡¾öÓÚAppBarLayoutµÄ¸ß¶È¡£
19. ÕÛµþ¸ß¶È（Collapsed height ）È¡¾öÓÚToolbarµÄ¸ß¶È¡£
20. Äã±ØÐëÔÚCollapsingAvatarToolbarÀïÃæÉèÖÃÍ·Ïñ（avatar）ºÍ±êÌâÊÓͼ（ title view），ÇÒid±ØÐëºÈÉÏÃæÑÝʾµÄÍêÈ«Ò»Ö¡£ÕâЩidÊÂlibraryÀïÃæµÄ¡£（ËùÒÔÊÇ@¶ø²»ÊÇ@＋）¡£
21. Äã¿ÉÒÔʹÓÃÈÎÒâTextView×÷Ϊtitle，ÒÔ¼°ÈÎÒâview×÷ΪͷÏñ，ÎÒÕâÀïµÄÀý×ÓÓõÄÊÇhdodenhofµÄCircleImageView ，µ«ÊÇÕâÈ¡¾öÓÚÄã×Ô¼º¡£
22. ÄãÒ²¿ÉÒÔÌí¼Ó¸ü¶àviewµ½CollapsingAvatarToolbarÀïÃæ¡£
23. ËùÓеÄ×Ô¶¨ÒåÊôÐÔ¶¼ÊÇ¿ÉÑ¡µÄ，Èç¹ûûÓÐÌṩ¾ÍʹÓÃĬÈ쵀 ¡£
24. * @author Administrator
25. * @see http://www.jcodecraeer.com/a/opensource/2015/0830/3385.html
26. */
27. public class CollapsingAvatarToolbar extends LinearLayout implements AppBarLayout.OnOffsetChangedListener {
29. private View avatarView;
30. private TextView titleView;
32. private float collapsedPadding;
33. private float expandedPadding;
35. private float expandedImageSize;
36. private float collapsedImageSize;
38. private float collapsedTextSize;
39. private float expandedTextSize;
41. private boolean valuesCalculatedAlready = false;
42. private Toolbar toolbar;
43. private AppBarLayout appBarLayout;
44. private float collapsedHeight;
45. private float expandedHeight;
46. private float maxOffset;
48. public CollapsingAvatarToolbar(Context context) {
49. this(context, null);
50. init();
51. }
53. public CollapsingAvatarToolbar(Context context, AttributeSet attrs) {
54. super(context, attrs);
55. init();
57. TypedArray a = context.getTheme().obtainStyledAttributes(attrs, R.styleable.CollapsingAvatarToolbar, 0, 0);
59. try {
60. collapsedPadding = a.getDimension(R.styleable.CollapsingAvatarToolbar_collapsedPadding, -1);
61. expandedPadding = a.getDimension(R.styleable.CollapsingAvatarToolbar_expandedPadding, -1);
63. collapsedImageSize = a.getDimension(R.styleable.CollapsingAvatarToolbar_collapsedImageSize, -1);
64. expandedImageSize = a.getDimension(R.styleable.CollapsingAvatarToolbar_expandedImageSize, -1);
66. collapsedTextSize = a.getDimension(R.styleable.CollapsingAvatarToolbar_collapsedTextSize, -1);
67. expandedTextSize = a.getDimension(R.styleable.CollapsingAvatarToolbar_expandedTextSize, -1);
68. } finally {
69. a.recycle();
70. }
72. final Resources resources = getResources();
73. if (collapsedPadding < 0) {
74. collapsedPadding = resources.getDimension(R.dimen.default_collapsed_padding);
75. }
76. if (expandedPadding < 0) {
77. expandedPadding = resources.getDimension(R.dimen.default_expanded_padding);
78. }
79. if (collapsedImageSize < 0) {
80. collapsedImageSize = resources.getDimension(R.dimen.default_collapsed_image_size);
81. }
82. if (expandedImageSize < 0) {
83. expandedImageSize = resources.getDimension(R.dimen.default_expanded_image_size);
84. }
85. if (collapsedTextSize < 0) {
86. collapsedTextSize = resources.getDimension(R.dimen.default_collapsed_text_size);
87. }
88. if (expandedTextSize < 0) {
89. expandedTextSize = resources.getDimension(R.dimen.default_expanded_text_size);
90. }
91. }
93. private void init() {
94. setOrientation(HORIZONTAL);
95. }
97. @NonNull
98. private AppBarLayout findParentAppBarLayout() {
99. ViewParent parent = this.getParent();
100. if (parent instanceof AppBarLayout) {
101. return ((AppBarLayout) parent);
102. } else if (parent.getParent() instanceof AppBarLayout) {
103. return ((AppBarLayout) parent.getParent());
104. } else {
105. throw new IllegalStateException("Must be inside an AppBarLayout");
106. //TODO actually, a collapsingtoolbar
107. }
108. }
110. protected void onAttachedToWindow() {
111. super.onAttachedToWindow();
112. findViews();
113. if (!isInEditMode()) {
114. appBarLayout.addOnOffsetChangedListener(this);
115. } else {
116. setExpandedValuesForEditMode();
117. }
118. }
120. private void setExpandedValuesForEditMode() {
121. calculateValues();
122. updateViews(1f, 0);
123. }
125. private void findViews() {
126. appBarLayout = findParentAppBarLayout();
127. toolbar = findSiblingToolbar();
128. avatarView = findAvatar();
129. titleView = findTitle();
130. }
132. @NonNull
133. private View findAvatar() {
134. View avatar = this.findViewById(R.id.cat_avatar);
135. if (avatar == null) {
136. throw new IllegalStateException("View with id ta_avatar not found");
137. }
138. return avatar;
139. }
141. @NonNull
142. private TextView findTitle() {
143. TextView title = (TextView) this.findViewById(R.id.cat_title);
144. if (title == null) {
145. throw new IllegalStateException("TextView with id ta_title not found");
146. }
147. return title;
148. }
150. @NonNull
151. private Toolbar findSiblingToolbar() {
152. ViewGroup parent = ((ViewGroup) this.getParent());
153. for (int i = 0, c = parent.getChildCount(); i < c; i++) {
154. View child = parent.getChildAt(i);
155. if (child instanceof Toolbar) {
156. return (Toolbar) child;
157. }
158. }
159. throw new IllegalStateException("No toolbar found as sibling");
160. }
162. @Override
163. public void onOffsetChanged(AppBarLayout appBarLayout, int offset) {
164. if (!valuesCalculatedAlready) {
165. calculateValues();
166. valuesCalculatedAlready = true;
167. }
168. float expandedPercentage = 1 - (-offset / maxOffset);
169. updateViews(expandedPercentage, offset);
170. }
172. private void calculateValues() {
173. collapsedHeight = toolbar.getHeight();
174. expandedHeight = appBarLayout.getHeight() - toolbar.getHeight();
175. maxOffset = expandedHeight;
176. }
178. private void updateViews(float expandedPercentage, int currentOffset) {
179. float inversePercentage = 1 - expandedPercentage;
180. float translation = -currentOffset + ((float) toolbar.getHeight() * expandedPercentage);
182. float currHeight = collapsedHeight + (expandedHeight - collapsedHeight) * expandedPercentage;
183. float currentPadding = expandedPadding + (collapsedPadding - expandedPadding) * inversePercentage;
184. float currentImageSize = collapsedImageSize + (expandedImageSize - collapsedImageSize) * expandedPercentage;
185. float currentTextSize = collapsedTextSize + (expandedTextSize - collapsedTextSize) * expandedPercentage;
187. setContainerOffset(translation);
188. setContainerHeight((int) currHeight);
189. setPadding((int) currentPadding);
190. setAvatarSize((int) currentImageSize);
191. setTextSize(currentTextSize);
192. }
194. private void setContainerOffset(float translation) {
195. this.setTranslationY(translation);
196. }
198. private void setContainerHeight(int currHeight) {
199. this.getLayoutParams().height = currHeight;
200. }
202. private void setPadding(int currentPadding) {
203. this.setPadding(currentPadding, 0, 0, 0);
204. }
206. private void setTextSize(float currentTextSize) {
207. titleView.setTextSize(TypedValue.COMPLEX_UNIT_PX, currentTextSize);
208. }
210. private void setAvatarSize(int currentImageSize) {
211. avatarView.getLayoutParams().height = currentImageSize;
212. avatarView.getLayoutParams().width = currentImageSize;
213. }
214. }

attr.xml

Xml´úÂë

1. <?xml version="1.0" encoding="utf-8"?>
2. <resources>
4. <declare-styleable name="CollapsingAvatarToolbar">
5. <attr name="collapsedPadding" format="dimension" />
6. <attr name="expandedPadding" format="dimension" />
7. <attr name="collapsedImageSize" format="dimension" />
8. <attr name="expandedImageSize" format="dimension" />
9. <attr name="collapsedTextSize" format="dimension" />
10. <attr name="expandedTextSize" format="dimension" />
11. </declare-styleable>
13. </resources>

ids.xml

Xml´úÂë

1. <?xml version="1.0" encoding="utf-8"?>
2. <resources>
3. <item name="cat_avatar" type="id"></item>
4. <item name="cat_title" type="id"></item>
5. </resources>

ʹÓÃ，α´úÂë：

Xml´úÂë

1. <android.support.design.widget.AppBarLayout
2. android:id="@+id/appbar"
3. android:layout_width="match_parent"
4. android:layout_height="200dp"
5. android:fitsSystemWindows="true"
6. android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" >
8. <!-- Èç¹ûÏëÖÆÔìtoolbarµÄÕÛµþЧ¹û，ÎÒÃDZØÐë°ÑToolbar·ÅÔÚCollapsingToolbarLayoutÖÐ： -->
9. <!-- ͨ³£，ÎÒÃÇÎÒÃǶ¼ÊÇÉèÖÃToolbarµÄtitle，¶øÏÖÔÚ，ÎÒÃÇÐèÒª°ÑtitleÉèÖÃÔÚCollapsingToolBarLayoutÉÏ，¶ø²»ÊÇToolbar¡£ -->
10. <!-- ¸øÐèÒªÓÐÕÛµþЧ¹ûµÄ×é¼þÉèÖà layout_collapseModeÊôÐÔ -->
11. <!-- Toolbar µÄ¸ß¶Èlayout_height±ØÐë¹Ì¶¨，²»ÄÜ ¡°wrap_content¡±，·ñÔòToolbar²»»á»¬¶¯，ҲûÓÐÕÛµþЧ¹û -->
12. <!-- app:contentScrim="?attr/colorPrimary"ÓÃÓÚÉèÖÃÊÕËõµÄʱºòToolbar×Ô¶¯±ä»¯µ½ÆÕͨµÄÑÕÉ« -->
13. <!-- app:titleEnabled="false"ÓÃÓÚÉèÖÃÊÇ·ñÏÔʾtitle，ĬÈÏΪÏÔʾ-->
14. <android.support.design.widget.CollapsingToolbarLayout
15. android:id="@+id/collapsingToolbarLayout"
16. android:layout_width="match_parent"
17. android:layout_height="match_parent"
18. app:layout_scrollFlags="scroll|exitUntilCollapsed"
19. android:fitsSystemWindows="true"
20. app:contentScrim="?attr/colorPrimary"
21. app:expandedTitleMarginEnd="64dp"
22. app:expandedTitleMarginStart="48dp"
23. app:titleEnabled="false"
24. >
26. <!-- ÖÆÔìÊÓ²îЧ¹û -->
27. <!-- CollapsingToolbarLayout»¹ÄÜÈÃÎÒÃÇ×ö³ö¸ü¸ß¼¶µÄ¶¯»­，±ÈÈçÔÚÀïÃæ·ÅÒ»¸öImageView，È»ºóÔÚËüÕÛµþµÄʱºò½¥½¥µ­³ö¡£Í¬Ê±ÔÚÓû§¹ö¶¯µÄʱºòtitleµÄ¸ß¶ÈÒ²»áËæןı䡣 -->
28. <!-- ΪÁËÖÆÔì³öÕâÖÖЧ¹û，ÎÒÃÇÌí¼ÓÒ»¸ö¶¨ÒåÁËapp:layout_collapseMode="parallax" ÊôÐÔµÄImageView¡£ -->
30. <ImageView
31. android:id="@+id/backdrop"
32. android:layout_width="match_parent"
33. android:layout_height="match_parent"
34. app:layout_collapseMode="parallax"
35. app:layout_collapseParallaxMultiplier="0.7"
36. app:layout_scrollFlags="scroll|enterAlways|enterAlwaysCollapsed"
37. android:fitsSystemWindows="true"
38. android:scaleType="centerCrop"
39. android:src="@drawable/bg_login" />
41. <android.support.v7.widget.Toolbar
42. android:id="@+id/toolbar"
43. android:layout_width="match_parent"
44. android:layout_height="?attr/actionBarSize"
45. app:layout_collapseMode="pin"
46. app:layout_scrollFlags="scroll|enterAlways"
47. app:popupTheme="@style/ThemeOverlay.AppCompat.Dark"
48. app:titleTextAppearance="@style/TextAppearance.AppCompat.Headline" />
50. <com.widget.view.CollapsingAvatarToolbar
51. android:layout_width="match_parent"
52. android:layout_height="?attr/actionBarSize"
53. android:gravity="center_vertical"
54. >
55. <!--
56. app:collapsedPadding="@dimen/collapsedPadding"
57. app:expandedPadding="@dimen/expandedPadding"
58. app:collapsedImageSize="@dimen/collapsedImageSize"
59. app:expandedImageSize="@dimen/expandedImageSize"
60. app:collapsedTextSize="@dimen/collapsedTextSize"
61. app:expandedTextSize="@dimen/expandedTextSize"
62. -->
64. <ImageView
65. android:id="@id/cat_avatar"
66. android:layout_width="wrap_content"
67. android:layout_height="wrap_content"
68. android:src="@drawable/face"
69. android:background="@drawable/default_face_bg"
70. android:padding="4dp"
71. />
73. <TextView
74. android:id="@id/cat_title"
75. android:layout_width="wrap_content"
76. android:layout_height="wrap_content"
77. android:textColor="@android:color/holo_blue_dark"
78. android:text="Name" />
79. </com.widget.view.CollapsingAvatarToolbar>
81. </android.support.design.widget.CollapsingToolbarLayout>
82. </android.support.design.widget.AppBarLayout>