本文实例分析了Android中GridView和ArrayAdapter用法。分享给大家供大家参考,具体如下:
GridView是一个表格化的二维排版的View,当GridView的文字放不下时会出现scrolling的效果,GridView中的元素命名为Item,要将Item放入GridView,需要ArrayAdapter对象。
例子如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.GridView;
import android.widget.TextView;
public class A06Activity extends Activity {
private TextView tv;
//两个按钮是动态放入GridView的开关,b01是设置GridView为两列格式,并放入4
//个item,b02设置为三列格式,并放入9个Item
private Button b01,b02; //
private GridView gv;
private String[] s1,s2;
private ArrayAdapter<String> aa;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super .onCreate(savedInstanceState);
setContentView(R.layout.main);
tv=(TextView)findViewById(R.id.tv);
b01=(Button)findViewById(R.id.button01);
b02=(Button)findViewById(R.id.button02);
gv=(GridView)findViewById(R.id.gv);
s1= new String[]{
getResources().getString(R.string.str_list01),
getResources().getString(R.string.str_list02),
getResources().getString(R.string.str_list03),
getResources().getString(R.string.str_list04)
};
s2= new String[]{
getResources().getString(R.string.str_list01),
getResources().getString(R.string.str_list02),
getResources().getString(R.string.str_list03),
getResources().getString(R.string.str_list04),
getResources().getString(R.string.str_list01),
getResources().getString(R.string.str_list02),
getResources().getString(R.string.str_list03),
getResources().getString(R.string.str_list04),
getResources().getString(R.string.str_list04)
};
b01.setOnClickListener( new OnClickListener(){
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
gv.setNumColumns( 2 );
aa= new ArrayAdapter<String>(A06Activity. this ,R.layout.list_item_l_small,s1);
gv.setAdapter(aa);
gv.setSelection( 2 );
gv.refreshDrawableState();
}
});
b02.setOnClickListener( new OnClickListener(){
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
gv.setNumColumns( 2 );
aa= new ArrayAdapter<String>(A06Activity. this ,R.layout.list_item_l_small,s2);
gv.setAdapter(aa);
}
});
//利用GridView的OnClickListener()方法用来捕捉用户单击的是哪个item
gv.setOnItemClickListener( new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// 判断Adapter中元素的个数,判断被单击的是第几个元素的名称
switch (aa.getCount()){
case 4 :
tv.setText(s1[arg2]);
break ;
case 9 :
tv.setText(s2[arg2]);
break ;
}
}
});
}
}
|
res/layout/main.xml如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
<? xml version = "1.0" encoding = "utf-8" ?>
< LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android"
android:layout_width = "fill_parent"
android:layout_height = "fill_parent"
android:orientation = "vertical" >
< TextView
android:id = "@+id/tv"
android:layout_width = "fill_parent"
android:layout_height = "wrap_content"
android:text = "@string/hello" />
< Button
android:id = "@+id/button01"
android:layout_width = "fill_parent"
android:layout_height = "wrap_content"
/>
< Button
android:id = "@+id/button02"
android:layout_width = "fill_parent"
android:layout_height = "wrap_content"
/>
< GridView
android:id = "@+id/gv"
android:layout_width = "fill_parent"
android:layout_height = "wrap_content"
></ GridView >
</ LinearLayout >
|
res/layout/list_item_l_small的作用是配置ArrayAdapter的第二个参数textViewResourceId,参数必须为TextView进行配置。若需要更改放入item的文字模式,可以通过这个来设置文字的大小、模式的属性设置,而一旦放入ArrayAdapter,这个配置会立即生效。也可以设置许多的layout xml,提供给不同的GridView使用,让每一个GridView都有不同的风貌。
1
2
3
4
5
6
7
8
9
10
11
12
13
|
<? xml version = "1.0" encoding = "utf-8" ?>
< TextView
xmlns:android = "http://schemas.android.com/apk/res/android"
android:id = "@+id/myCheckedTextView1"
android:layout_width = "match_parent"
android:layout_height = "match_parent"
android:textColor = "@drawable/blue"
android:textSize = "12dp"
android:textAppearance = "@android:attr/textAppearanceLarge"
android:gravity = "center_vertical"
android:paddingLeft = "6dip"
android:minHeight = "@android:attr/listPreferredItemHeight"
/>
|
希望本文所述对大家Android程序设计有所帮助。