问题描述

保存哈希图的ArrayList

在savedInstanceState()中保存数据。保存ArrayList<HashMap<String,String>>。但是目前还没实现，代码如下：

@Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putParcelableArrayList("places", (ArrayList<? extends Parcelable>) places);

    }

restore()方法

private void restore(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        //What should i do here! i have try many things but none of them is helping

    }

解决方案

  ArrayList< HashMap< String,String>> arr = new ArrayList< HashMap< String,String>> ();

    @Override
    protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putParcelableArrayList("places", (ArrayList<    ? extends Parcelable>) arr);
    }

   @Override
   protected void onRestoreInstanceState(Bundle savedInstanceState) {

   ArrayList<HashMap<String,String>> a = (ArrayList<HashMap<String,String>>)savedInstanceState.get("places");
   /*for(int i =0; i< a.size(); i++){
        HashMap<String,String> map = a.get(i);
        for(String s : map.keySet()){
            Log.d("log",s+" :: "+map.get(s));
        }
    }*/
}

解决方案二：

ArrayList, HashMap和String是Serializable，你可以使用Bundle.putSerializable 和 Bundle.getSerializable

@Override
protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putSerializable("places", places);
}

private void restore(Bundle savedInstanceState) {
    if (savedInstanceState != null) {
        places = (ArrayList<HashMap<String,String>>) savedInstanceState.getSerializable("places");
    }
}

还有注意从onRestoreInstanceState或者onCreate调用restore