工具欄標題消失在摺疊狀態下改變方向時，

Question

我想創建一個可摺疊工具欄像chesesquare庫中的一個，但我面臨這個問題：

https://www.youtube.com/watch?v=THdxcyEc1CA&feature=youtu.be

任何人知道如何解決這個問題？

Answer 1

您可以檢查配置更改（方向）AppBarLayout的狀態，存放。然後，您可以在應用配置更改後爲AppBarLayout設置該狀態。

public class CheeseDetailActivity extends AppCompatActivity { 

public static final String EXTRA_NAME = "cheese_name"; 
AppBarLayout appBarLayout; 
boolean isCollapsed = false; 

//state change listener 
AppBarLayout.OnOffsetChangedListener toolbarStateListener = new AppBarLayout.OnOffsetChangedListener() { 
    @Override 
    public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) { 
     if (verticalOffset == 0) { 
      // Collapsed 
      isCollapsed = true; 
     } else { 
      // Not collapsed 
      isCollapsed = false; 

     } 
    } 
}; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_detail); 

    Intent intent = getIntent(); 
    final String cheeseName = intent.getStringExtra(EXTRA_NAME); 

    final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 
    getSupportActionBar().setDisplayHomeAsUpEnabled(true); 

    CollapsingToolbarLayout collapsingToolbar = 
      (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar); 
    collapsingToolbar.setTitle(cheeseName); 

    //getting app bar layout 
    appBarLayout = (AppBarLayout) findViewById(R.id.appbar); 
    //set listener to listen state change of app bar layout 
    appBarLayout.addOnOffsetChangedListener(toolbarStateListener); 

    loadBackdrop(); 
} 


@Override 
public void onSaveInstanceState(Bundle savedInstanceState) { 
    super.onSaveInstanceState(savedInstanceState); 
    //save state on orientation change 
    savedInstanceState.putBoolean("isCollapsed", isCollapsed); 
} 

@Override 
public void onRestoreInstanceState(Bundle savedInstanceState) { 
    super.onRestoreInstanceState(savedInstanceState); 
    //get state on orientation change 
    isCollapsed = savedInstanceState.getBoolean("isCollapsed"); 
} 

@Override 
protected void onResume() { 
    super.onResume(); 
    //set state of app bar layout 
    appBarLayout.setExpanded(isCollapsed); 
} 

private void loadBackdrop() { 
    final ImageView imageView = (ImageView) findViewById(R.id.backdrop); 
    Glide.with(this).load(Cheeses.getRandomCheeseDrawable()).centerCrop().into(imageView); 
} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.sample_actions, menu); 
    return true; 
} 
} 

我在CheeseSquare存儲庫中編輯了CheeseDetailActivity。

Answer 2

在onConfigurationChanged你可以嘗試運行

handler.postDelayed(new Runnable(){ 
    @Overrride 
    public void run(){ 
     toolbar.invalidate(); 
    } 
},[Try different time lapses(miliseconds)]);