android的简单入门学习

package com.example.dailphone;

import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.text.TextUtils;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import android.os.Build;

public class MainActivity extends ActionBarActivity {
	
	/** 拨打电话按钮 */
	private Button bt_dail;
	
	/** 输入电话时的文本框 */
	private EditText et_number;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//获得按钮
	    bt_dail = (Button) findViewById(R.id.bt_dail);
	    //获得文本框
	    et_number = (EditText) MainActivity.this.findViewById(R.id.et_number);
	    //给按钮添加事件
		bt_dail.setOnClickListener(new MyLisenner());
	}
	
	private class MyLisenner implements OnClickListener {
		@Override
		public void onClick(View v) {
			String number = et_number.getText().toString();
			//判空操作给出"吐丝"提示
			if (TextUtils.isEmpty(number)) {
				Toast toast = Toast.makeText(MainActivity.this, "号码不能为空", Toast.LENGTH_SHORT);
				toast.show();
				return ;
			}
			//意图， 想干一件什么事情  （泡茶）
			Intent intent = new Intent();
			intent.setAction(Intent.ACTION_CALL);
			intent.setData(Uri.parse("tel:" + number));
			startActivity(intent);
		}
		
	}

}