[android] activity基础

//MainActivity
package cn.eoe.helloeoe;

import android.support.v7.app.ActionBarActivity;
import android.R.string;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;


public class MainActivity extends ActionBarActivity {

    private Button btnStartAty1;
    private TextView tvOut;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btnStartAty1 = (Button) findViewById(R.id.btnStartAty1);
        tvOut = (TextView) findViewById(R.id.tvOut);
        
        btnStartAty1.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                Intent i = new Intent(MainActivity.this, Aty1.class);
                i.putExtra("text", "get from main");
//                startActivity(i);
                
                startActivityForResult(i, 0);
            }
        });
        
        
        
        System.out.println("onCreate!!");
    }
    
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        
        String result = data.getStringExtra("result");
        tvOut.setText(result);
        super.onActivityResult(requestCode, resultCode, data);
    }

    @Override
    protected void onStart() {
        System.out.println("onStart");
        super.onStart();
    }
    
    @Override
    protected void onResume() {
        System.out.println("onResume");
        super.onResume();
    }
    
    @Override
    protected void onPause() {
        System.out.println("onPause");
        super.onPause();
    }
    
    @Override
    protected void onStop() {
        System.out.println("onStop");
        super.onStop();
    }
    
    @Override
    protected void onDestroy() {
        System.out.println("onDestroy");
        super.onDestroy();
    }
    
    @Override
    protected void onRestart() {
        System.out.println("onRestart");
        super.onRestart();
    }
    
}

//son activity
public class Aty1 extends Activity {
    
    private Button btnClose;
    private TextView tvOut;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.aty1);
        
        btnClose = (Button) findViewById(R.id.btnClose);
        btnClose.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                Intent result = new Intent();
                result.putExtra("result", "from Aty1");
                setResult(0,result);
                finish();
            }
        });
        
        tvOut = (TextView) findViewById(R.id.tvOut);
        String fromMain = getIntent().getStringExtra("text");
        tvOut.setText(fromMain);
    }
}

btnStartAty1.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                Intent i = new Intent(MainActivity.this, Aty1.class);
                i.putExtra("text", "get from main");
//                startActivity(i);
                startActivityForResult(i, 0);
            }
        });

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        
        String result = data.getStringExtra("result");
        tvOut.setText(result);
        super.onActivityResult(requestCode, resultCode, data);
    }