android各种返回写法

Button.setOnClickListener(mGoBack);
public OnClickListener mGoBack = new OnClickListener() {

    public void onClick(View v) {
        finish();
    }
};

要返回上一个activity，只需结束当前的activity

有两Activity~A和BA运行启动BActivity保留A情形B结束时候传回参数A~~~
我用startActivity发现创建了新Activity~~~
能保留A现场啊
A启动B时样写

Intent intent=new Intent(MainActivity.this,SecMainActivity.class);
 startActivityForResult(intent, 1);

@Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
  // TODO Auto-generated method stub ...

在android中重写父类的onkeydown方法，就可以更方便的操作了。
Android代码  收藏代码
@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
// TODO Auto-generated method stub 
if(keyCode==KeyEvent.KEYCODE_BACK&&event.getRepeatCount()==0){ 
    //需要处理 
} 
    return false; 
} 
长按事件
Java代码  收藏代码
@Override 
public boolean onKeyLongPress(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_CALL) { 
        // a long press of the call key. 
        // do our work, returning true to consume it. by 
        // returning true, the framework knows an action has 
        // been performed on the long press, so will set the 
        // canceled flag for the following up event. 
        return true; 
    } 
    return super.onKeyLongPress(keyCode, event); 
} 


Java代码  收藏代码
@Override 
public boolean onKeyUp(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_CALL && event.isTracking() 
            && !event.isCanceled()) { 
        // if the call key is being released, AND we are tracking 
        // it from an initial key down, AND it is not canceled, 
        // then handle it. 
        return true; 
    } 
    return super.onKeyUp(keyCode, event); 
} 
 
@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_0) { 
        // this tells the framework to start tracking for 
        // a long press and eventual key up. it will only 
        // do so if this is the first down (not a repeat). 
        event.startTracking(); 
        return true; 
    } 
    return super.onKeyDown(keyCode, event); 
} 
 
@Override 
public boolean dispatchKeyEvent(KeyEvent event) { 
    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK) { 
        if (event.getAction() == KeyEvent.ACTION_DOWN 
                && event.getRepeatCount() == 0) { 
 
            // Tell the framework to start tracking this event. 
            getKeyDispatcherState().startTracking(event, this); 
            return true; 
 
        } else if (event.getAction() == KeyEvent.ACTION_UP) { 
            getKeyDispatcherState().handleUpEvent(event); 
            if (event.isTracking() && !event.isCanceled()) { 
 
                // DO BACK ACTION HERE 
                return true; 
 
            } 
        } 
        return super.dispatchKeyEvent(event); 
    } else { 
        return super.dispatchKeyEvent(event); 
    } 
}