如何以程序化的方式隐藏 imageview

Question

我创建了一个 linearlayout，有三个 icons：

<ImageView
            android:id="@+id/cities"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content          
            android:src="@drawable/city" />

        <ImageView
            android:id="@+id/red"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"           
            android:src="@drawable/red"
            android:visibility="gone" 
            />
        <ImageView
            android:id="@+id/deal"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"       
            android:src="@drawable/deal" />

最初中间的图标是隐藏的（android:visibility="gone"），我想在登录界面上登录成功时，图标显示出来。下面的方法不对，如何实现？

public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.fyelogin);                    
            etPassword = (EditText)findViewById(R.id.password);
            btnLogin = (Button)findViewById(R.id.login_button);
            btnCancel = (Button)findViewById(R.id.cancel_button);
            lblResult = (TextView)findViewById(R.id.result);
            final ImageView details = (ImageView)findViewById(R.id.red); 
             btnLogin.setOnClickListener(new OnClickListener() {
             public void onClick(View v) {
                    String password = etPassword.getText().toString();
                     if(password.equals("guest")){
                        lblResult.setText("password successful.");

 giving error @ this line  ----->  details.setVisibility(View.VISIBLE);
                     } else {
                        lblResult.setText("password doesn't match.");
                     }
                     finish();} });

Answer 1

你后面有个finish()方法，Activity关闭了就是显示了ImageView也看不到

把finish()去掉就能看到了