Android系列之LinearLayout+EditText+Button+AlertDialog

這個簡單的例子是EditText中默認有個字符串text，單擊Show按鈕，彈出AlertDialog顯示EditText中的內容，單擊Clear按鈕，清除EditText中的內容！！

Activity用到兩個LinearLayout,兩個Button,一個TextView,一個EditText！

main.xml代碼如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<EditText
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/text"
    android:id="@+id/text"
    />
<LinearLayout
	android:id="@+id/linearlayout1"
	android:layout_width="fill_parent"
	android:layout_height="wrap_content"
	android:gravity="center"
	>
	<Button
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:text="@string/btnShow"
		android:id="@+id/btnShow"
		/>
	<Button
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:text="@string/btnClear"
		android:id="@+id/btnClear"
		/>
</LinearLayout>
</LinearLayout>

java代碼

 1 import android.app.Activity;
 2  import android.app.AlertDialog;
 3  import android.os.Bundle;
 4  import android.view.View;
 5 import android.widget.Button;
 6 import android.widget.EditText;
 7 
 8 public class practice extends Activity {
 9     Button btnShow;
10     Button btnClear;
11     EditText text;
12     /** Called when the activity is first created. */
13     @Override
14     public void onCreate(Bundle savedInstanceState) {
15         super.onCreate(savedInstanceState);
16         setContentView(R.layout.main);
17         
18         btnShow = (Button)findViewById(R.id.btnShow);
19         btnClear = (Button)findViewById(R.id.btnClear);
20         text = (EditText)findViewById(R.id.text);
21         
22         btnShow.setOnClickListener(new View.OnClickListener() {
23             
24             @Override
25             public void onClick(View v) {
26                 // TODO Auto-generated method stub
27                     new AlertDialog.Builder(practice.this)
28                     .setTitle("Infomation")
29                     .setIcon(android.R.drawable.ic_dialog_dialer)
30                     .setMessage(text.getText())
31                     .show();
32             }
33         });
34         
35         btnClear.setOnClickListener(new View.OnClickListener() {
36             
37             @Override
38             public void onClick(View v) {
39                 // TODO Auto-generated method stub
40                 text.setText("");
41             }
42         });
43     }
44 }

轉自：http://www.cnblogs.com/jk1001/archive/2010/08/12/1798105.html