单击弹出菜单时,为什么导航栏出现在全屏应用程序中

我有一个全屏应用程序:

MainActivity.java:

public class MainActivity extends AppCompatActivity {

@TargetApi(Build.VERSION_CODES.KITKAT)
private void removeControlBar(){
    View decorView = getWindow().getDecorView();
    decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
            | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_FULLSCREEN
            | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
}
@Override
public void onResume(){
    super.onResume();
    removeControlBar();
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@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 id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

}

表现:

它是全屏的,但当我点击弹出菜单时,导航栏(包括家,后面的栏)出现了!

题:

为什么会这样？

我该如何修复它(避免出现导航栏)？

(我试图删除标题栏并添加带有弹出菜单的ImageButton,但它完全相同!)感谢您的帮助!

您正试图通过在onresume方法中调用它来管理粘性沉浸.这意味着一旦状态被更改,它将不会恢复,直到下一个活动恢复.

摆脱这个 private void removeControlBar()

您需要通过windows onfocuschanged方法进行管理.

这样可以处理警报,并且在处理弹出窗口时导航栏等不会返回到视图.

@Override
public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    if (hasFocus) {
        decorView.setSystemUiVisibility(
            View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
            | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_FULLSCREEN
            | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
    }
}

该文档使用粘性浸泡和详细的解释在这里.