[Android]自定义带删除输入框

标签：android   自定义   带删除输入框   edittext   

在项目开发中，带删除按钮输入框也是人们常常用到的，该文章便介绍一下如何创建一个带删除输入框。其中，需要解决的问题如下：

a)创建自定义editText类

b)在自定义editText中显示删除图片

c)根据输入框的输入情况显示或隐藏图片

d)点击删除图片文字消失，图片隐藏

e)根据输入框焦点失去和获得状态显示或隐藏图片

好了，问题明确了，开始实现功能：

a)创建一个名为MyClearEditText的class文件，并集成EditText，实现其构造方法：

	public MyClearEditText(Context context) {
		this(context, null);
		// TODO Auto-generated constructor stub
	}

	public MyClearEditText(Context context, AttributeSet attrs) {
		this(context, attrs, android.R.attr.editTextStyle);
		// TODO Auto-generated constructor stub
	}

	public MyClearEditText(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
	}

b)在editText中，我们若想显示上下左右方向的图片，有着setCompoundDrawables或setCompoundDrawablesWithIntrinsicBounds方法，具体的话，可以去百度一下其区别，在这里，我使用的是setCompoundDrawablesWithIntrinsicBounds方法。代码如下：

	/**
	 * 初始化清除的图片
	 */
	private void initClearDrawable() {
		draw = getCompoundDrawables()[2];

		// 判断清除的图片是否为空
		if (draw == null) {
			draw = getResources().getDrawable(R.drawable.editdelete);
		}

		// 为输入框设置图片
		this.setCompoundDrawablesWithIntrinsicBounds(null, null, draw, null);
	}

c)需要获得输入框的情况，便要实现TextWatcher接口。

监听：

		this.addTextChangedListener(this);

	public void onTextChanged(CharSequence text, int start, int lengthBefore,
			int lengthAfter) {
		// 判断输入框中是否有内容
		if (text.length() > 0) {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, draw, null);
		} else {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
		}
	}

	public void beforeTextChanged(CharSequence s, int start, int count,
			int after) {
		// TODO Auto-generated method stub

	}

	public void afterTextChanged(Editable s) {
		// TODO Auto-generated method stub

	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
		// 判断触碰是否结束
		if (event.getAction() == MotionEvent.ACTION_UP) {
			// 判断所触碰的位置是否为清除的按钮
			if (event.getX() > (getWidth() - getTotalPaddingRight())
					&& event.getX() < (getWidth() - getPaddingRight())) {
				// 将editText里面的内容清除
				setText("");
			}
		}
		return super.onTouchEvent(event);
	}

e）既然是根据焦点的得失来判断，当然是实现焦点监听的方法：

	@Override
	protected void onFocusChanged(boolean focused, int direction,
			Rect previouslyFocusedRect) {
		// TODO Auto-generated method stub
		super.onFocusChanged(focused, direction, previouslyFocusedRect);
		// 判断焦点失去和得到时的操作
		if (focused && !this.getText().toString().equals("")) {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, draw, null);
		} else {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
		}
	}

package com.xiaoyan.xiaoyanlibrary.common.widget.edittext;

import com.xiaoyan.xiaoyanlibrary.R;

import android.content.Context;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.EditText;

/**
 * 自定义一个具有清除功能的editText
 * 
 * @author xiejinxiong
 * 
 */
public class MyClearEditText extends EditText implements TextWatcher {
	/** 储存清除的图片 */
	private Drawable draw;

	public MyClearEditText(Context context) {
		this(context, null);
		// TODO Auto-generated constructor stub
	}

	public MyClearEditText(Context context, AttributeSet attrs) {
		this(context, attrs, android.R.attr.editTextStyle);
		// TODO Auto-generated constructor stub
	}

	public MyClearEditText(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);

		initClearDrawable();
		this.addTextChangedListener(this);
	}

	@Override
	protected void onFocusChanged(boolean focused, int direction,
			Rect previouslyFocusedRect) {
		// TODO Auto-generated method stub
		super.onFocusChanged(focused, direction, previouslyFocusedRect);
		// 判断焦点失去和得到时的操作
		if (focused && !this.getText().toString().equals("")) {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, draw, null);
		} else {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
		}
	}

	/**
	 * 初始化清除的图片
	 */
	private void initClearDrawable() {
		draw = getCompoundDrawables()[2];

		// 判断清除的图片是否为空
		if (draw == null) {
			draw = getResources().getDrawable(R.drawable.editdelete);
		}

		// 将输入框默认设置为没有清除的按钮
		this.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
	}

	public void onTextChanged(CharSequence text, int start, int lengthBefore,
			int lengthAfter) {
		// 判断输入框中是否有内容
		if (text.length() > 0) {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, draw, null);
		} else {
			this.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null);
		}
	}

	public void beforeTextChanged(CharSequence s, int start, int count,
			int after) {
		// TODO Auto-generated method stub

	}

	public void afterTextChanged(Editable s) {
		// TODO Auto-generated method stub

	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
		// 判断触碰是否结束
		if (event.getAction() == MotionEvent.ACTION_UP) {
			// 判断所触碰的位置是否为清除的按钮
			if (event.getX() > (getWidth() - getTotalPaddingRight())
					&& event.getX() < (getWidth() - getPaddingRight())) {
				// 将editText里面的内容清除
				setText("");
			}
		}
		return super.onTouchEvent(event);
	}

}

[Android]自定义带删除输入框

标签：android   自定义   带删除输入框   edittext   

原文地址：http://blog.csdn.net/u011596810/article/details/46970009