如何在点击时隐藏和显示菜单项图标？

Question

我正在开发一个直播流媒体收音机，并在操作栏图标中给出了控件，如播放和通过菜单项停止图标。所有这些项目都很完美。我想要的是，当我开始我的应用程序时，它会显示只播放图标项目，当我点击播放图标，流获取开始和停止图标将出现，而不是玩...当我按停止图标，然后播放图标出现。在播放音乐时，如媒体播放器中出现暂停按钮，并在出现按下暂停按钮时播放按钮。 我不能得到这方面的任何解决方案，我用我整天在这...请帮助我获得解决方案

这是XML代码

<?xml version="1.0" encoding="utf-8"?> 
    <menu 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto"> 
    <item 
     android:id="@+id/play" 
     android:icon="@drawable/ic_play" 
     app:showAsAction="ifRoom|withText" 
     android:title="Play" /> 
    <item 
     android:id="@+id/pause" 
     android:icon="@drawable/ic_pause" 
     app:showAsAction="always" 
     android:title="Pause" /> 
</menu> 

这是我的主要活动代码

//STARTING GET MEDIA FUNCTION 
private void getMedia() { 
    try { 
     mediaPlayer = new MediaPlayer(); 
     url = new URL(address); 
     mediaPlayer.setDataSource(String.valueOf(url)); 
     mediaPlayer.prepareAsync(); 
     mediaPlayer.setOnErrorListener(new MediaPlayer.OnErrorListener() { 
      @Override 
      public boolean onError(MediaPlayer mp, int what, int extra) { 
       return false; 
      } 
     }); 

     mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() { 

      @Override 
      public void onPrepared(MediaPlayer mp) { 
       bConnected = true; 
       if (bShouldPlay) { 
        mediaPlayer.start(); 

       } 
       Toast.makeText(getBaseContext(), "Connected...", Toast.LENGTH_LONG).show(); 
      } 
     }); 
    } catch (MalformedURLException e) { 
     e.printStackTrace(); 
    } catch (IOException e) { 
     e.printStackTrace(); 
    } 
} 

//ONCREATE FUNCTION START 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    bConnected = false; 
    bShouldPlay = false; 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    private Document Getdata() { 
     try { 
     url = new URL(address); 
     connection= (HttpURLConnection) url.openConnection(); 
     connection.setRequestMethod("GET"); 
     inputStream = connection.getInputStream(); 
     builderFactory= DocumentBuilderFactory.newInstance(); 
     builder= builderFactory.newDocumentBuilder(); 
     xmlDoc = builder.parse(inputStream); 
     return xmlDoc; 
    } catch (Exception e) { 
     e.printStackTrace(); 
     return null; 
    } 
} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    onCreateOptionsMenu(menu); 
    inflator.inflate(R.menu.menu, menu); 

    return false; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    bConnected = false; 
    bShouldPlay = false; 

    switch (item.getItemId()) { 
     case R.id.actionPlay: 
      if (bConnected) { 
       mediaPlayer.start(); 

       Toast.makeText(getBaseContext(), "Playing...", Toast.LENGTH_LONG).show(); 

      } else { 

       bShouldPlay = true; 
       getMedia(); 
     Toast.makeText(getBaseContext(), "Still connecting...", Toast.LENGTH_LONG).show(); 
      } 
      Toast.makeText(getBaseContext(), "Connected...", Toast.LENGTH_LONG).show(); 
      break; 

case R.id.actionStop: 
      if (mediaPlayer.isPlaying()) { 
       Toast.makeText(this, "Stopping Media Player....", Toast.LENGTH_LONG).show(); 
       mediaPlayer.stop(); 
       mediaPlayer.release(); 
       bConnected = false; 
       bShouldPlay = false; 
       Toast.makeText(this, "Media Player is Stopped....", Toast.LENGTH_LONG).show(); 

      } 
      break; 
     default: 
      break; 
    } 
    return super.onOptionsItemSelected(item); 
} 

请帮我解决这个..

Answer 1

一个菜单项会做，只是动态更改菜单布局象下面这样：

private boolean isPlay = false; 
@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.your_menu, menu); 
    MenuItem Item = menu.findItem(R.id.action_play_pause); 

    Item.setActionView(R.layout.play); 
    Item.getActionView().setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      if(isPlay){ 
       Item.setActionView(R.id.pause); //image view with pause icon 
      }else { 
       Item.setActionView(R.id.play); //image view with play icon 
      } 
      isPlay = !isPlay; 
     } 
    }); 
    return super.onCreateOptionsMenu(menu); 
} 

希望这有助于

Answer 2

另一种选择，而不是由Du.Fantasy提供的一个是：

首先你应该增加，能见度停止按钮=去yourxml：

<?xml version="1.0" encoding="utf-8"?> 
    <menu 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto"> 
<item 
    android:id="@+id/play" 
    android:icon="@drawable/ic_play" 
    app:showAsAction="ifRoom|withText" 
    android:title="Play" /> 
<item 
    android:id="@+id/pause" 
    android:icon="@drawable/ic_pause" 
    app:showAsAction="always" 
    android:title="Pause" /> 
<item 
    android:id="@+id/stop" 
    android:icon="@drawable/ic_stop" 
    android:visibility="gone" 
    android:title="Stop" /> 

</menu> 

然后在您的代码中，您可以通过ID获取物品，并将其可见性动态设置为可见或者例如如下所示：

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    bConnected = false; 
    bShouldPlay = false; 

    switch (item.getItemId()) { 
     case R.id.actionPlay: 
      if (bConnected) { 
       mediaPlayer.start(); 
       item.setVisible(View.GONE); 
       menu.findItem(R.id.ic_pause).setVisibility(View.VISIBLE); 
       menu.findItem(R.id.ic_stop).setVisibility(View.VISIBLE); 

       Toast.makeText(getBaseContext(), "Playing...", Toast.LENGTH_LONG).show(); 

      } else { 

       bShouldPlay = true; 
       getMedia(); 
     Toast.makeText(getBaseContext(), "Still connecting...", Toast.LENGTH_LONG).show(); 
      } 
      Toast.makeText(getBaseContext(), "Connected...", Toast.LENGTH_LONG).show(); 
      break; 

case R.id.actionStop: 
      if (mediaPlayer.isPlaying()) { 
       item.setVisible(View.GONE); 
       menu.findItem(R.id.ic_play).setVisibility(View.VISIBLE); 
       menu.findItem(R.id.ic_pause).setVisibility(View.GONE); 

       Toast.makeText(this, "Stopping Media Player....", Toast.LENGTH_LONG).show(); 
       mediaPlayer.stop(); 
       mediaPlayer.release(); 
       bConnected = false; 
       bShouldPlay = false; 
       Toast.makeText(this, "Media Player is Stopped....", Toast.LENGTH_LONG).show(); 

      } 
      break; 
     case R.id.actionPause: 
      item.setVisible(View.GONE); 
      menu.findItem(R.id.ic_play).setVisibility(View.VISIBLE); 
      menu.findItem(R.id.ic_stop).setVisibility(View.VISIBLE);  
     default: 
      break; 
    } 
    return super.onOptionsItemSelected(item); 
} 

我希望这可以帮助您了解隐藏和显示某些项目的想法。