Chapter 4

toeknee581 · November 30th, 2010, 12:36 AM

I have created my ClearableEditText class, and created my clearable_edit_text.xml. I'm not sure how to change my main.xml to use the new compound control. I've searched a ton on how to use compound controls and I can't find anything. The API demo code doesn't seem to have real examples of compound controls either.

Any help would be appreciated.

My clearable_edit_text.xml

Code:

<?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">
	<EditText android:layout_height="wrap_content" android:id="@+id/editText"
		android:layout_width="fill_parent" />
	<Button android:layout_height="wrap_content" android:text="Clear"
		android:layout_width="fill_parent" android:id="@+id/clearButton" />
</LinearLayout>

My main.xml

Code:

<?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">
	<EditText android:id="@+id/myEditText" android:layout_width="fill_parent"
		android:layout_height="wrap_content" android:text="New To Do Item" />
	<ListView android:id="@+id/myListView" android:layout_width="fill_parent"
		android:layout_height="wrap_content" />
</LinearLayout>

my ClearableEditText.java file

Code:

package com.paad.todolist;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;

public class ClearableEditText extends LinearLayout {

	EditText editText;
	Button clearButton;

	public ClearableEditText(Context context) {
		super(context);

		// inflate the view from the layout resource
		String infService = Context.LAYOUT_INFLATER_SERVICE;
		LayoutInflater li;
		li = (LayoutInflater) getContext().getSystemService(infService);
		li.inflate(R.layout.clearable_edit_text, this, true);

		// get references to the child controls
		editText = (EditText) findViewById(R.id.editText);
		clearButton = (Button) findViewById(R.id.clearButton);

		hookupButton();
	}

	private void hookupButton() {
		clearButton.setOnClickListener(new OnClickListener() {

			public void onClick(View v) {
				editText.setText("");

			}
		});
	}

	public ClearableEditText(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
	}

}

Joon Hong · April 18th, 2012, 02:42 AM

I know this is an old post, but I hope this reply will be helpful to others :)

To use ClearableEditText in xml file, you should create constructor with Context and AttributeSet like this:

Code:

	public ClearableEditTextBox(Context context, AttributeSet attrs) {
		super(context, attrs);
		drawCompoundControlUi();
		hookupButton();
	}

Xml cannot instantiate compound control classes if they don't have that 2 arguments.

That's all. enjoy using it in activities like other controls/widgets :)

Code:

<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android">
 	<wroxexample.helloandroid.ClearableTextBox
 	    android:id="@+id/clearTextBox"
 	    android:layout_width="fill_parent"
 	    android:layout_height="wrap_content"
 	    />
</merge>