-
通过Intent意图传值
方式一:
页面A:Intent intent = new Intent(A.this,B.class);
intent.putExtra(kay,value);
startActivity(intent);页面B:Intent intent = getIntent(); intent.getStringExtra(kay);
方式二:
页面A:Intent intent = new Intent(A.this,B.class);
Bundle bundle = new Bundle();
bundle.putString(key,value);
input.putExtras(bundle);
startActivity(intent);
页面 B:Intent intent = getIntent();
Bundle bundle = intent.getExtras();
bundle.getString(key);
静态成员变量传值(不建议使用)
方式:1.在页面A中声明一个公共的静态成员变量,在合适的位置存入数据
2.直接访问页面A中的静态成员变量,读取相应的内容-
全局变量传值(Application)
方式:1.创建Application的子类,并且在类中声明全局变量
public class MyApplication extends Application {//应用的全局变量 public Map<String,Object> data = new HashMap<String, Object>(); }
2.在清单文件<Application />中通过android:name="包名.类名"引入
3.在页面A合适位置存入数据
MyApplication application = (MyApplication) getApplication();//不能new MyApplication要用getApplication得到Application对象,向下转型得到MyApplication
application.data.put("name", "小翠");
application.data.put("age", 21);
4.在页面B中取数据
MyApplication application = (MyApplication) getApplication();
String name = application.data.get("name").toString();
int age =Integer.parseInt(application.data.get("age").toString());
- 回传数据
以选取用户头像为例:
页面A:startActivityForResult(intent,requestCode);
页面B:setResult(resultCode,Intent data);
页面A:重写onActivityResult(requestCode,resultCode);
页面A代码:
public class MainActivity extends Activity {
private ImageView iv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
iv = (ImageView) findViewById(R.id.iv);
}
public void show(View v)
{
Intent intent = new Intent(MainActivity.this, InfoActivity.class);
//带返回数据启动Activity
startActivityForResult(intent, 110);
}
/**
* 获取回传的数据
*
* int requestCode 请求码
* int resultCode 结果码
* Intent data 意图(带着返回参数)
*/
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if(requestCode==110 && resultCode == RESULT_OK)
{
//为图片控件设置内容
int imageId = data.getIntExtra("imageId", R.drawable.ic_launcher);
iv.setImageResource(imageId);
}
}
}
页面B:
public class InfoActivity extends Activity {
private RadioGroup rg;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_info);
rg = (RadioGroup) findViewById(R.id.rg);
}
//点击按钮后,将图片的ID 回传给MainActivity页面
public void submit(View v)
{
//1, 得到当前选中的RadionButton的id
int checkId = rg.getCheckedRadioButtonId();
//图片的ID
int imageId = R.drawable.ic_launcher;
switch (checkId) {
case R.id.rb1:
imageId = R.drawable.img_31;
break;
case R.id.rb2:
imageId = R.drawable.img_32;
break;
case R.id.rb3:
imageId = R.drawable.img_33;
break;
case R.id.rb4:
imageId = R.drawable.img_42;
break;
case R.id.rb5:
imageId = R.drawable.img_43;
break;
case R.id.rb6:
imageId = R.drawable.img_44;
break;
}
/**
* 通过startActivityForResult() 开启的界面, 需要有返回值,
*
* 则必须要通过 setResult() 方法返回数据
*
* resultCode 返回码
*
* data intent意图对象
*/
Intent data = new Intent();
data.putExtra("imageId", imageId);
setResult(RESULT_OK, data);
//关闭当前Activity页面
finish();
}
}