Android應用中TextView垂直滾動

在Android中TextView可以輕松實現橫向跑馬燈效果，但是對垂直滾動沒有直接的支持方法，於是百度上谷歌，谷歌上百度，最終還是沒有發現一個拿來即用的demo，呵呵，於是自己研究了下，寫了一個可以實現TextView垂直滾動的demo，由於項目需要，在這裡我使用的是AbsoluteLayout布局，左右鍵切換時更改滾動內容，希望此demo能給有同樣需求的童鞋們帶來幫助！

---寫在前面

textscroll.xml配置：

1. <?xml version="1.0" encoding="utf-8"?>
2. <AbsoluteLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:layout_width="match_parent"
4. android:layout_height="match_parent"
5. android:orientation="vertical" >
7. <TextView
8. android:id="@+id/tScroll"
9. android:layout_width="fill_parent"
10. android:layout_height="wrap_content"
11. android:maxLines="5"
12. android:scrollbars="none"
13. android:singleLine="false"
14. android:textColor="#FF0000" >
15. </TextView>
17. </AbsoluteLayout>

Java代碼：

1. package sue.test;
3. import java.util.ArrayList;
4. import java.util.List;
6. import com.amttgroup.element.Container;
7. import com.amttgroup.element.RootLayout;
8. import com.amttgroup.element.Text;
9. import com.amttgroup.utils.G;
11. import android.app.Activity;
12. import android.graphics.Color;
13. import android.os.Bundle;
14. import android.os.Handler;
15. import android.util.Log;
16. import android.view.Gravity;
17. import android.view.KeyEvent;
18. import android.widget.AbsoluteLayout;
19. import android.widget.TextView;
21. public class TextScrollActivity extends Activity {
22. TextView tv;
23. String L = "TextScrollActivity";
24. List<String> welcomeWords = new ArrayList<String>();
25. int curIndex = 0;
27. @Override
28. protected void onCreate(Bundle savedInstanceState) {
29. super.onCreate(savedInstanceState);
31. welcomeWords
32. .add(" Linux公社（LinuxIDC.com）於2006年9月25日注冊並開通網站，Linux現在已經成為一種廣受關注和支持的一種操作系統，IDC是互聯網數據中心，LinuxIDC就是關於Linux的數據中心。Linux公社是專業的Linux系統門戶網站，實時發布最新Linux資訊，包括Linux、Ubuntu、Fedora、RedHat、紅旗Linux、Linux教程、Linux認證、SUSE Linux、Android、Oracle、Hadoop等技術。");
33. welcomeWords
34. .add(" It is an honor for you to stay at the Beijing Hotel. On behalf of the staff at the Beijing Hotel, I sincerely welcome you.Built in 1900, Beijing Hotel is a luxury hotel with a long history. We have elegant guestrooms, exquisite cuisine, convenient facilities and entertainment facilities. It is our pleasure to offer you the best services.Have a nice stay!");
36. setContentView(R.layout.textscroll);
38. tv = (TextView) findViewById(R.id.tScroll);
40. /**
41. * 動態設置坐標及寬和高，也可以忽略，在配置文件中設置
42. */
43. AbsoluteLayout.LayoutParams lp = (AbsoluteLayout.LayoutParams) tv
44. .getLayoutParams();
45. lp.x = 300;
46. lp.y = 300;
47. lp.width = 500;
48. lp.height = 170;
50. tv.setTextSize(16);
51. tv.setTextColor(Color.WHITE);
52. tv.setGravity(Gravity.LEFT);
54. tv.setText(welcomeWords.get(curIndex));
56. h.postDelayed(r, 3000);
57. }
59. Handler h = new Handler();
60. int i = 0;
61. Runnable r = new Runnable() {
63. @Override
64. public void run() {
65. int height = tv.getHeight();
66. int scrollY = tv.getScrollY();
67. int lineHeight = tv.getLineHeight();
68. int lineCount = tv.getLineCount();//總行數
69. /**
70. * textView不可見內容的高度，可以理解為偏移位移
71. */
72. int maxY = (tv.getLineCount() * tv.getLineHeight()
73. + tv.getPaddingTop() + tv.getPaddingBottom())
74. - tv.getHeight();
76. Log.e("=maxY=", maxY+"");
77. Log.e("=height=", height+"");
78. Log.e("=lineCount=", tv.getLineCount()+"");
80. double viewCount = Math.floor(height / lineHeight);//可見區域最大顯示多少行
81. if (lineCount > viewCount) {//總行數大於可見區域顯示的行數時則滾動
83. if (scrollY >= maxY) {
84. tv.scrollBy(0, -maxY);
85. } else {
86. tv.scrollBy(0, lineHeight);
87. }
88. h.postDelayed(this, 3000);
89. }
91. }
93. };
95. public boolean onKeyDown(int keyCode, KeyEvent event) {
97. switch (keyCode) {
98. case KeyEvent.KEYCODE_DPAD_UP:
100. break;
101. case KeyEvent.KEYCODE_DPAD_DOWN:
103. break;
104. case KeyEvent.KEYCODE_DPAD_RIGHT:
106. handle();
107. break;
108. case KeyEvent.KEYCODE_DPAD_LEFT:
110. handle();
111. break;
112. case KeyEvent.KEYCODE_DPAD_CENTER:
113. handle();
114. break;
115. case KeyEvent.KEYCODE_ENTER:
116. handle();
117. break;
118. case KeyEvent.KEYCODE_BACK:
119. finish();
121. break;
122. default:
124. }
125. return super.onKeyDown(keyCode, event);
126. }
128. public void handle() {
130. h.removeCallbacks(r);
134. curIndex = (curIndex + 1) % 2;
136. tv.setText(welcomeWords.get(curIndex));
138. h.postDelayed(r, 3000);
140. }
142. @Override
143. public void onDestroy() {
144. super.onDestroy();
145. h.removeCallbacks(r);
146. }
148. }