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通過Intent意圖傳值
方式一:
頁面A:Intent intent = new Intent(A.this,B.class);
intent.putExtra(kay,value);
startActivity(intent);頁面B:Intent intent = getIntent(); intent.getStringExtra(kay);
方式二:
頁面A:Intent intent = new Intent(A.this,B.class);
Bundle bundle = new Bundle();
bundle.putString(key,value);
input.putExtras(bundle);
startActivity(intent);
頁面 B:Intent intent = getIntent();
Bundle bundle = intent.getExtras();
bundle.getString(key);
靜態成員變量傳值(不建議使用)
方式:1.在頁面A中聲明一個公共的靜態成員變量,在合適的位置存入數據
2.直接訪問頁面A中的靜態成員變量,讀取相應的內容-
全局變量傳值(Application)
方式:1.創建Application的子類,并且在類中聲明全局變量
public class MyApplication extends Application {//應用的全局變量 public Map<String,Object> data = new HashMap<String, Object>(); }
2.在清單文件<Application />中通過android:name="包名.類名"引入
3.在頁面A合適位置存入數據
MyApplication application = (MyApplication) getApplication();//不能new MyApplication要用getApplication得到Application對象,向下轉型得到MyApplication
application.data.put("name", "小翠");
application.data.put("age", 21);
4.在頁面B中取數據
MyApplication application = (MyApplication) getApplication();
String name = application.data.get("name").toString();
int age =Integer.parseInt(application.data.get("age").toString());
- 回傳數據
以選取用戶頭像為例:
頁面A:startActivityForResult(intent,requestCode);
頁面B:setResult(resultCode,Intent data);
頁面A:重寫onActivityResult(requestCode,resultCode);
頁面A代碼:
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);
//帶返回數據啟動Activity
startActivityForResult(intent, 110);
}
/**
* 獲取回傳的數據
*
* int requestCode 請求碼
* int resultCode 結果碼
* Intent data 意圖(帶著返回參數)
*/
@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)
{
//為圖片控件設置內容
int imageId = data.getIntExtra("imageId", R.drawable.ic_launcher);
iv.setImageResource(imageId);
}
}
}
頁面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);
}
//點擊按鈕后,將圖片的ID 回傳給MainActivity頁面
public void submit(View v)
{
//1, 得到當前選中的RadionButton的id
int checkId = rg.getCheckedRadioButtonId();
//圖片的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;
}
/**
* 通過startActivityForResult() 開啟的界面, 需要有返回值,
*
* 則必須要通過 setResult() 方法返回數據
*
* resultCode 返回碼
*
* data intent意圖對象
*/
Intent data = new Intent();
data.putExtra("imageId", imageId);
setResult(RESULT_OK, data);
//關閉當前Activity頁面
finish();
}
}