如何从操作栏更新布局的内容？

Question

我想检查操作栏菜单中的选项后，从布局更新某个按钮的状态。

我有一个操作栏菜单下面的代码：

@Override 
     public boolean onOptionsItemSelected(MenuItem item) { 
      // Handle action bar item clicks here. The action bar will 
      // automatically handle clicks on the Home/Up button, so long 
      // as you specify a parent activity in AndroidManifest.xml. 

      int delay = 150; // delay 150 ms. 

    switch (item.getItemId()){ 
     case R.id.action_disconnect: 
      data.saveData(this.getApplicationContext()); 

       Disconnect(); 

      return true; 
     case R.id.action_check: 

      if (item.isChecked()) 
      { 
      // here i want to update button status 
       item.setChecked(false); 
       ledControl.instance.data.expertMode = false; 
       ledControl.instance.data.configExpertMode = 1; 
       ledControl.instance.data.sendConfigTurnLightMessage(); 

      } 
      else { 
       item.setChecked(true); 
       ledControl.instance.data.expertMode = true; 
// here i want to update button status 
      } 
       return true; 
     default: 
      return super.onOptionsItemSelected(item); 
    } 
      } 

这里是布局类控制按钮加载为片段

public class BlinkFragment extends Fragment implements View.OnClickListener { 

     private Switch switch_b1, switch_b2; 
     private DiscreteSeekBar discrete_bl_g, discrete_bl_h; 

     @Override 
     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
      // Inflate the layout for this fragment 
      View v = inflater.inflate(R.layout.fragment_blink, container, false); 
        switch_b1 = (Switch) v.findViewById(R.id.switch_b1); 
      switch_b2 = (Switch) v.findViewById(R.id.switch_b2); 
      discrete_bl_g = (DiscreteSeekBar) v.findViewById(R.id.discrete_bl_g); 
      discrete_bl_h = (DiscreteSeekBar) v.findViewById(R.id.discrete_bl_h); 
    discrete_bl_g.setEnabled(ledControl.instance.data.expertMode); 
      discrete_bl_h.setEnabled(ledControl.instance.data.expertMode); 

    } 
} 

我有这种方法试试：

 fragment = new BlinkFragment(); 
     FragmentManager fm = getSupportFragmentManager(); 
     FragmentTransaction ft = fm.beginTransaction(); 
     ft.replace(R.id.fragment2, fragment); 
     ft.commit(); 

Answer 1

你的问题有点不清楚。
我想你想从具有ActionBar的Activity改变BlinkFragment的视图。

以下代码将帮助您？

呼叫BlinkFragment的从YourActivity方法：

public class YourActivity extends AppCompatActivity { 

    ... 

    private BlinkFragment getBlinkFragment() { 
     return (BlinkFragment) getSupportFragmentManager().findFragmentById(R.id.fragment2); 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 

     int delay = 150; // delay 150 ms. 

     switch (item.getItemId()){ 
      case R.id.action_disconnect: 
       data.saveData(this.getApplicationContext()); 
       Disconnect(); 
       getBlinkFragment.onDisconnected(); 

       return true; 
      case R.id.action_check: 

       if (item.isChecked()) 
       { 
        // here i want to update button status 
        item.setChecked(false); 
        ledControl.instance.data.expertMode = false; 
        ledControl.instance.data.configExpertMode = 1; 
        ledControl.instance.data.sendConfigTurnLightMessage(); 
       } 
       else { 
        item.setChecked(true); 
        ledControl.instance.data.expertMode = true; 
        // here i want to update button status 
       } 
       getBlinkFragment.onLedControlChanged(ledControl); 
       return true; 
      default: 
       return super.onOptionsItemSelected(item); 
     } 
    } 
    .... 
} 

BlinkFragment会象下面这样：

public class BlinkFragment extends Fragment implements View.OnClickListener { 

    ... 

    public void onLedControlChanged(LedControl ledControl) { 
     // change the view 
     discrete_bl_g.setEnabled(ledControl.instance.data.expertMode); 
     discrete_bl_h.setEnabled(ledControl.instance.data.expertMode); 
    } 

    public void onDisconnected() { 
     // change the view 
    } 
}