android 使用include 调用内部组件
例子一:
sublayout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#505050"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="SubLayout"
/>
<Button
android:id="@+id/mybutton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=" A Button "
/>
</LinearLayout>
mail.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<include android:id="@+id/main1" layout="@layout/sublayout" />
<include android:id="@+id/main2" layout="@layout/sublayout" />
<Button
android:id="@+id/startanotheractivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=" Start Another Activity "
/>
</LinearLayout>
如何调用组件include进来的组件呢。
package com.AndroidIncludeLayout;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class AndroidIncludeLayout extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
View subLayout1 = (View)findViewById(R.id.main1);
View subLayout2 = (View)findViewById(R.id.main2);
Button myButton_main1 = (Button)subLayout1.findViewById(R.id.mybutton);
Button myButton_main2 = (Button)subLayout2.findViewById(R.id.mybutton);
Button startAnotherActivity = (Button)findViewById(R.id.startanotheractivity);
startAnotherActivity.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setClass(AndroidIncludeLayout.this, AnotherActivity.class);
startActivity(intent);
}});
myButton_main1.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Toast.makeText(AndroidIncludeLayout.this, "Button 1 Pressed", Toast.LENGTH_LONG).show();
}});
myButton_main2.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Toast.makeText(AndroidIncludeLayout.this, "Button 2 Pressed", Toast.LENGTH_LONG).show();
}});
}
}
但是如果include进来的xml,是
sublayout.xml
<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="SubLayout"
/>
<Button
android:id="@+id/mybutton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=" A Button "
/>
</merge>
则以上的方法将不能实现,会报空指针。
因为用了merge后,导入进来就相当于是当前view下的组件了,所以直接
findViewById就可以了。
这样的话。。。可以解决了include 多次同一个layout的问题