Android入門教程之Gallery

本文的效果圖：

main.xml源碼:

[xhtml]

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:orientation="vertical"
4. android:layout_width="fill_parent"
5. android:layout_height="fill_parent"
6. >
7. <Gallery android:id="@+id/gallery" android:layout_height="fill_parent" android:layout_width="fill_parent"></Gallery>
8. </LinearLayout>

程序源碼：

[java]

1. package com.testImageView;
3. import java.lang.reflect.Field;
4. import java.util.ArrayList;
6. import android.app.Activity;
7. import android.content.Context;
8. import android.graphics.Bitmap;
9. import android.graphics.BitmapFactory;
10. import android.os.Bundle;
11. import android.view.View;
12. import android.view.ViewGroup;
13. import android.widget.AdapterView;
14. import android.widget.BaseAdapter;
15. import android.widget.Gallery;
16. import android.widget.ImageView;
17. import android.widget.AdapterView.OnItemClickListener;
19. public class testImageView extends Activity {
20. private Gallery mGallery;
21. @Override
22. public void onCreate(Bundle savedInstanceState) {
23. super.onCreate(savedInstanceState);
24. setContentView(R.layout.main);
26. mGallery = (Gallery)findViewById(R.id.gallery);
27. try {
28. mGallery.setAdapter(new ImageAdapter(this));
29. } catch (IllegalArgumentException e) {
30. // TODO Auto-generated catch block
31. e.printStackTrace();
32. } catch (IllegalAccessException e) {
33. // TODO Auto-generated catch block
34. e.printStackTrace();
35. }
36. mGallery.setOnItemClickListener(new OnItemClickListener() {
37. public void onItemClick(AdapterView parent, View v, int position, long id) {
38. testImageView.this.setTitle(String.valueOf(position));
39. }
40. });
41. }
43. /*
44. * class ImageAdapter is used to control gallery source and operation.
45. */
46. private class ImageAdapter extends BaseAdapter{
47. private Context mContext;
48. private ArrayList<Integer> imgList=new ArrayList<Integer>();
49. private ArrayList<Object> imgSizes=new ArrayList<Object>();
50. public ImageAdapter(Context c) throws IllegalArgumentException, IllegalAccessException{
51. mContext = c;
53. //用反射機制來獲取資源中的圖片ID和尺寸
54. Field[] fields = R.drawable.class.getDeclaredFields();
55. for (Field field : fields)
56. {
57. if (!"icon".equals(field.getName()))//除了icon之外的圖片
58. {
59. int index=field.getInt(R.drawable.class);
60. //保存圖片ID
61. imgList.add(index);
62. //保存圖片大小
63. int size[]=new int[2];
64. Bitmap bmImg=BitmapFactory.decodeResource(getResources(),index);
65. size[0]=bmImg.getWidth();size[1]=bmImg.getHeight();
66. imgSizes.add(size);
67. }
68. }
69. }
70. @Override
71. public int getCount() {
72. // TODO Auto-generated method stub
74. return imgList.size();
75. }
77. @Override
78. public Object getItem(int position) {
79. // TODO Auto-generated method stub
81. return position;
82. }
84. @Override
85. public long getItemId(int position) {
86. // TODO Auto-generated method stub
88. return position;
89. }
91. @Override
92. public View getView(int position, View convertView, ViewGroup parent) {
93. // TODO Auto-generated method stub
95. ImageView i = new ImageView (mContext);
96. //從imgList取得圖片ID
97. i.setImageResource(imgList.get(position).intValue());
98. i.setScaleType(ImageView.ScaleType.FIT_XY);
99. //從imgSizes取得圖片大小
100. int size[]= new int[2];
101. size=(int[]) imgSizes.get(position);
102. i.setLayoutParams(new Gallery.LayoutParams(size[0], size[1]));
103. return i;
104. }
106. };
107. }