单击两次以关闭抽屉布局中带有吐司的应用程序

Question

在我的主要 activity 中有抽屉布局，通过查看 this 我试图添加建议用户单击后退按钮两次以关闭应用程序的功能

但在我的例子中，当关闭 DrawerLayout 时，它显示 toast 消息，但我不想要它，而是想在 activity 空闲时显示它。

 boolean doubleBackToExitPressedOnce = false;

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);}
//        } else {
//            super.onBackPressed();
//        }
        if (doubleBackToExitPressedOnce) {
            super.onBackPressed();
            return;
        }

        this.doubleBackToExitPressedOnce = true;
        Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();

        new Handler().postDelayed(new Runnable() {

            @Override
            public void run() {
                doubleBackToExitPressedOnce=false;
            }
        }, 2000);
    }

Answer 1

如果你的抽屉是打开然后关闭它并且return到避免 toast

if (drawer.isDrawerOpen(GravityCompat.START)) {
    drawer.closeDrawer(GravityCompat.START);

    return;
}

Answer 2

如果您的抽屉已打开，请先关闭再执行逻辑

@Override
public void onBackPressed() {
    DrawerLayout drawer = findViewById(R.id.drawer_layout);
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawer(GravityCompat.START);
    } else {
        if (doubleBackToExitPressedOnce) {
            super.onBackPressed();
            return;
        }
        doubleBackToExitPressedOnce = true;
        Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                doubleBackToExitPressedOnce = false;
            }
        }, 2000);
    }
}

单击两次以关闭抽屉布局中带有吐司的应用程序

click back twice to close app with toast in drawer layout

java

android

drawerlayout

onbackpressed