android – 如何在对话框中维护沉浸式模式？

当我的活动显示自定义对话框时,如何保持新的沉浸式模式？

我使用下面的代码来维护对话框中的沉浸模式,但是使用该解决方案,当我启动自定义对话框时,NavBar会出现不到一秒钟,然后它就会消失.

以下视频更好地解释了问题(当NavBar出现时,请查看屏幕底部)：http://youtu.be/epnd5ghey8g

我该如何避免这种行为？

码

我申请中所有活动的父亲：

public abstract class ImmersiveActivity extends Activity {

    @SuppressLint("NewApi")
    private void disableImmersiveMode() {
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
            getWindow().getDecorView().setSystemUiVisibility(
                    View.SYSTEM_UI_FLAG_FULLSCREEN
            );
        }
    }

    @SuppressLint("NewApi")
    private void enableImmersiveMode() {
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
            getWindow().getDecorView().setSystemUiVisibility(
                      View.SYSTEM_UI_FLAG_LAYOUT_STABLE 
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION 
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN 
                    | View.SYSTEM_UI_FLAG_FULLSCREEN 
                    | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY 
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
            );
        }
    }


    /**
     * Set the Immersive mode or not according to its state in the settings:
     * enabled or not.
     */
    protected void updateSystemUiVisibility() {
        // Retrieve if the Immersive mode is enabled or not.
        boolean enabled = getSharedPreferences(Util.PREF_NAME, 0).getBoolean(
                "immersive_mode_enabled", true);

        if (enabled) enableImmersiveMode();
        else disableImmersiveMode();
    }

    @Override
    public void onResume() {
        super.onResume();
        updateSystemUiVisibility();
    }

    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
        updateSystemUiVisibility();
    }

}

我的所有自定义Dialog都在他们的onCreate(…)方法中调用此方法：

/**
 * Copy the visibility of the Activity that has started the dialog {@link mActivity}. If the
 * activity is in Immersive mode the dialog will be in Immersive mode too and vice versa.
 */
@SuppressLint("NewApi")
private void copySystemUiVisibility() {
    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
        getWindow().getDecorView().setSystemUiVisibility(
                mActivity.getWindow().getDecorView().getSystemUiVisibility()
        );
    }
}

编辑 – 解决方案(感谢Beaver6813,详细了解他的答案)：

我的所有自定义对话框都以这种方式覆盖show方法：

/**
 * An hack used to show the dialogs in Immersive Mode (that is with the NavBar hidden). To
 * obtain this, the method makes the dialog not focusable before showing it, change the UI
 * visibility of the window like the owner activity of the dialog and then (after showing it)
 * makes the dialog focusable again.
 */
@Override
public void show() {
    // Set the dialog to not focusable.
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
            WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE);

    copySystemUiVisibility();

    // Show the dialog with NavBar hidden.
    super.show();

    // Set the dialog to focusable again.
    getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE);
}

解决方法:

在对这个问题进行了大量研究后,对此进行了一次黑客修复,其中涉及撕毁Dialog类以寻找.即使在将UI可见性添加到管理器之前设置了UI可见性,也会在将对话框窗口添加到窗口管理器时显示导航栏.在Android Immersive example,评论说：

// * Uses semi-transparent bars for the nav and status bars
// * This UI flag will *not* be cleared when the user interacts with the UI.
// When the user swipes, the bars will temporarily appear for a few seconds and then
// disappear again.

我相信这就是我们在这里看到的(当一个新的,可聚焦的窗口视图被添加到管理器时,用户交互被触发).

我们如何解决这个问题？在我们创建对话框时使对话框不可聚焦(因此我们不触发用户交互),然后在显示后使其可聚焦.

//Here's the magic..
//Set the dialog to not focusable (makes navigation ignore us adding the window)
dialog.getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE, WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE);

//Show the dialog!
dialog.show();

//Set the dialog to immersive
dialog.getWindow().getDecorView().setSystemUiVisibility(
context.getWindow().getDecorView().getSystemUiVisibility());

//Clear the not focusable flag from the window
dialog.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE);

显然这不是理想的,但它似乎是一个Android bug,他们应该检查Window是否有沉浸式设置.

我已经将我的工作测试代码(原谅hacky messiness)更新到Github.我已经在Nexus 5模拟器上进行了测试,它可能会比KitKat更糟糕但只能用于概念验证.

标签：android,android-4-4-kitkat,android-activity,dialog,android-dialog
来源： https://codeday.me/bug/20190918/1810473.html