外部Activity和fragment之间的切换，传值

下，Activity A

/*下6h，*//*传值*//*跳转到Activity的Fragment中*/Intent intent = new Intent();intent.putExtra("username", cardNumStr);//String A, int bintent.putExtra("usernameflag", 11);//String A, int bintent.setClass(UserLoginActivity.this, MainPrepareActivity.class);startActivity(intent);UserLoginActivity.this.finish();

下，Activity B

@Override    protected void onResume() {        super.onResume();    int userloginId = getIntent().getIntExtra("usernameflag", 0);    if (userloginId == 11) {      setTabSelection(3);//此句从外部的Activity切换到       /* settingImage.setImageResource(R.mipmap.setting_selected);        settingText.setTextColor(Color.WHITE);        Toast.makeText(MainPrepareActivity.this, "点击了设置tab", Toast.LENGTH_SHORT).show();        SettingFragment sfts = new SettingFragment();        FragmentManager fmrs = getSupportFragmentManager();        FragmentTransaction ftns = fmrs.beginTransaction();        ftns.replace(R.id.Preoare_content_fl, sfts);        ftns.commit();*/     }}

下，SettingFragment.java

//获取用户名，并显示在标头
private TextView login;
login = (TextView) view.findViewById(R.id.login);
String username = getActivity().getIntent().getStringExtra("username");find_and_modify_text_view(username);
private void find_and_modify_text_view(String username) {    CharSequence text_view_old = login.getText();    login.setText(username + text_view_old);}