第一章:初入Android大门(弹出对话框)

效果:








main.xml

<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
android:id="@+id/widget0"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<Button
android:id="@+id/alert"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="&#24377;&#20986;&#23545;&#35805;&#26694;"
android:layout_x="122px"
android:layout_y="141px"
/>
</AbsoluteLayout>

strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, AlertTest!</string>
     <string name="title">消息提示</string>
     <string name="text">我很好！</string>
     <string name="buttonValue">确定</string>
    <string name="app_name">AlertTest</string>
</resources>

package alert.test;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class AlertTest extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        /** 载入main.xml */
        setContentView(R.layout.main);
        /** 找到button组件 */
        Button bt=(Button)findViewById(R.id.alert);
        /** 设置Button按钮的监听事件 */
        bt.setOnClickListener(new Button.OnClickListener(){
        	public void onClick(View v){
        		/** 当前Activity对象传进 AlertDialog,指当前窗口弹出对话框*/
        		Builder builder=new AlertDialog.Builder(AlertTest.this);
        		/** 设置对话框的标题*/
        		builder.setTitle(R.string.title);
        		/** 设置对话框的内容*/
        		builder.setMessage(R.string.text);
        		/** 设置对话框的里按钮的Value值和设置按钮的点击事件并且弹出对话框*/
        		builder.setPositiveButton(R.string.buttonValue, new DialogInterface.OnClickListener(){
						@Override
						public void onClick(DialogInterface dialog, int which) {
							/** 离开程序*/
							finish();
						}
        		}).show();
        	}
        });
    }
}