因此,我一直在论坛中寻找如何做到这一点,但我发现没有任何效果。当我在图像按钮上调用setVisibility()时,该按钮不受影响。下面是我在onCreate方法中的代码,当我运行应用程序时,这两个按钮都会显示出来。但是,如果我要将属性硬编码到xml文件中,则可见性会发生变化。任何想法为什么会发生这种情况?
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn1 = new ImageButton(this);
btn1.setVisibility(GONE);
btn2 = new ImageButton(this);
btn2.setVisibility(GONE);
答案 0 :(得分:3)
将您的代码更改为:
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn1 = (ImageButton)findViewById(R.id.btn1);
btn1.setVisibility(View.GONE);
btn2 = (ImageButton)findViewById(R.id.btn2);
btn2.setVisibility(View.GONE);
并修改main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:gravity="center_horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
>
<Button android:id="@+id/btn1" android:layout_width="100dip"
android:layout_height="40dip" android:text="btn1"/>
<Button android:id="@+id/btn2" android:layout_width="100dip"
android:layout_height="40dip" android:text="btn2"/>
</LinearLayout>
答案 1 :(得分:0)
第一:你应该像这样使用setVisibility方法:
btn1.setVisibility(VIEW.GONE),// not setVisibility(GONE);
SECONDE:
您已创建按钮,但you didn't add them to your activity
,(您的活动内容为(R.layout.main
)
试试这个:
super.onCreate(savedInstanceState);
btn1 = new ImageButton(this);
setContentView(btn1);
btn1.setVisibility(VIEW.GONE);
try{
Thread.sleep(3000);//pause 3 secondes
}catch(Exception e){}
btn1.setVisibility(View.VISIBLE);
编辑:
super.onCreate(savedInstanceState);
LinearLayout layout = new LinearLayout(this);
ImageButton btn1 = new ImageButton(this);
ImageButton btn2 = new ImageButton(this);
layout.addView(btn1);
layout.addView(btn2);
setContentView(layout);
btn1.setVisibility(VIEW.GONE);
btn2.setVisibility(VIEW.VISIBLE);
try{
Thread.sleep(3000);//pause 3 secondes
}catch(Exception e){}
btn1.setVisibility(View.VISIBLE);
btn2.setVisibility(VIEW.GONE);