intent

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class ActivityMain extends Activity {
	
	private Button myButton = null;
	
	
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        myButton = (Button) this.findViewById(R.id.myButton);
        myButton.setOnClickListener(new MyButtonListener());
    }
    
    /**
     * 内部类——按钮监听
     * @author dell
     *
     */
    class MyButtonListener implements OnClickListener{

		@Override
		public void onClick(View arg0) {
			// TODO Auto-generated method stub
			Intent it = new Intent();
			it.putExtra("key", "123");
			it.setClass(ActivityMain.this, Activity2.class); //从ActivityMain跳到Activity2
			ActivityMain.this.startActivity(it);
			
		}
    	
    }
}

public class Activity2 extends Activity{
	
	private TextView myTextView = null;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		this.setContentView(R.layout.activity2);
		Intent it = this.getIntent();
		String value = it.getStringExtra("key");
		System.out.println(value+"=======");
		myTextView = (TextView) this.findViewById(R.id.myTextView);
		myTextView.setText(value);
	}

}