使用Android提供的大量標准Action，Category調用系統Activity

Android提供了大量的標准Action，Category：

例子，查看並獲取聯系人電話

用戶點擊按鈕值會顯示系統的聯系人列表，當用戶單擊聯系人之後，程序將會顯示該聯系人的名字和電話

MainActivity.java

package com.hust.getcontacts;

import android.app.Activity;
import android.content.CursorLoader;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;


public class MainActivity extends Activity {
    
	final int PICK_CONTACT=0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button btn=(Button) findViewById(R.id.button1);
        
        btn.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				//創建intent
				Intent intent=new Intent();
				//設置Intent的Action屬性
				intent.setAction(Intent.ACTION_GET_CONTENT);
				//設置Intent的Type屬性
				intent.setType("vnd.android.cursor.item/phone");
				//啟動Activity，並希望獲取該Activity的結果
				startActivityForResult(intent,PICK_CONTACT);
			}        	
        });       
        
    }
    
//重寫該方法，處理返回的聯系人數據在參數Intent data中
    @Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		// TODO Auto-generated method stub
		super.onActivityResult(requestCode, resultCode, data);
		switch(requestCode)
		{
		 case (PICK_CONTACT):
			  if(resultCode==Activity.RESULT_OK){//Activity.RESULT_OK標准Activity結果 -1
				  //獲取返回的聯系人數據
				  Uri contactdata=data.getData();
				  CursorLoader cursorloader=new CursorLoader(this, contactdata, null, null, null, null);
				  //查詢聯系人信息表
				  Cursor cursor=cursorloader.loadInBackground();
				  //如果查詢到指定的聯系人
				  if(cursor.moveToFirst()){
					 //獲取聯系人的Id
					  String contactId=cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));
					  //獲取聯系人的名字
					  String name=cursor.getString(cursor.getColumnIndexOrThrow(ContactsContract.Contacts.DISPLAY_NAME));
				      String phoneNumber="此聯系人暫未輸入電話號碼";
				      
				      //根據聯系人查詢該聯系人的詳細信息
				      Cursor phones=getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, ContactsContract.CommonDataKinds.Phone.CONTACT_ID+"="+contactId, null, null);
				     //
				      if(phones.moveToFirst()){
				    	  //取出電話號碼
				    	  phoneNumber=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
				      }
				      phones.close();
				      
				      EditText show=(EditText) findViewById(R.id.editText1);
				      show.setText(name);
				      EditText phone=(EditText) findViewById(R.id.editText2);
				      phone.setText(phoneNumber);
				      
				  }
				  cursor.close();
			  }
		        break;
			
		
		}
	}


	@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}