Java ImageButton上的运动事件错误单击
这是代码Java ImageButton上的运动事件错误单击,java,android,pointers,events,motion,Java,Android,Pointers,Events,Motion,这是代码 public class AddActivity extends Activity implements OnClickListener{ String[] info = new String[11]; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.add_layout
public class AddActivity extends Activity implements OnClickListener{
String[] info = new String[11];
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_layout);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
TextView keyString = (TextView)findViewById(R.id.keyString);
TextView site1 = (TextView)findViewById(R.id.site1);
TextView site2 = (TextView)findViewById(R.id.site2);
TextView site3 = (TextView)findViewById(R.id.site3);
ImageButton submit = (ImageButton)findViewById(R.id.submit);
ImageButton add1 = (ImageButton)findViewById(R.id.add1);
ImageButton add2 = (ImageButton)findViewById(R.id.add2);
ImageButton add3 = (ImageButton)findViewById(R.id.add3);
submit.setOnClickListener((OnClickListener) this);
add1.setOnClickListener((OnClickListener) this);
add2.setOnClickListener((OnClickListener) this);
add3.setOnClickListener((OnClickListener) this);
int id = v.getId();
switch(id){
case R.id.submit:{
submitEntry(info);
break;
}
case R.id.add1:{
add2.setVisibility(View.VISIBLE);
site2.setVisibility(View.VISIBLE);
break;
}
}
}
}
这就是XML。add1、add2、add3和submit ImageButtons都在滚动视图中
当我按下add1 ImageButton时,我希望add2和site2 ImageButton变得可见,但它会抛出以下错误
运动事件的指针计数0无效;值必须介于1和16之间
我做错了什么
PS:所有findViewById调用都在onClick方法中,因为如果我在onCreate中调用它们,就会抛出NullPointerExection。findViewById调用,尤其是setOnClickListener调用应该在onCreate中。由于onClick中有setOnClickListener,我怀疑onClick是否被调用过 我们需要更多的日志才能找到确切的问题。在onclick中找到的那些viewbydcall没有意义。不确定为什么在onCreate中调用它们时会出现空指针异常。在本例中,不会调用onClick,因为创建活动时没有分配按钮来查看onClick方法;这些按钮将默认为没有指定侦听器。将活动用作onclick侦听器也不是一个好主意 您的代码应该如下所示:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/key_string"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="invisible" />
<EditText
android:id="@+id/keyString"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:visibility="invisible" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/site_string"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="invisible" />
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageButton
android:id="@+id/add1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_action_new" />
<EditText
android:id="@+id/site1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/url_hint"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="invisible" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageButton
android:id="@+id/add2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_action_new"
android:visibility="invisible" />
<EditText
android:id="@+id/site2"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:text="@string/url_hint"
android:textAppearance="?android:attr/textAppearanceLarge"
android:visibility="invisible" />
</LinearLayout>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="invisible" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageButton
android:id="@+id/add3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_action_new"
android:visibility="invisible" />
<EditText
android:id="@+id/site3"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:text="@string/url_hint"
android:visibility="invisible"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:visibility="invisible" />
<Button
android:id="@+id/submit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/submit_buttom" />
</LinearLayout>
</ScrollView>
</LinearLayout>
非常感谢你!另外,我认为在onCreate中声明它时出错,因为在XML中,submit是一个按钮,而我在AddActivity类中将它声明为ImageButton。只是为其他人做准备!
public class AddActivity extends Activity {
// https://source.android.com/source/code-style.html
// info -> mInfo; non-public, non-static field!
String[] mInfo = new String[11];
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_layout);
TextView keyString = (TextView)findViewById(R.id.keyString);
TextView site1 = (TextView)findViewById(R.id.site1);
TextView site2 = (TextView)findViewById(R.id.site2);
TextView site3 = (TextView)findViewById(R.id.site3);
Button submit = (Button)findViewById(R.id.submit);
ImageButton add1 = (ImageButton)findViewById(R.id.add1);
ImageButton add2 = (ImageButton)findViewById(R.id.add2);
ImageButton add3 = (ImageButton)findViewById(R.id.add3);
add1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
add2.setVisibility(View.VISIBLE);
site2.setVisibility(View.VISIBLE);
}
});
submit.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
submitEntry(mInfo);
}
});
}